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• 1. [Article] Optimal irrigation management : a framework, model, and application for optimizing irrigation when supplies are limited

  Many regions in North America are experiencing water shortages, and these conditions are expected to worsen. The next generation of irrigation scheduling applications must therefore be capable of providing ...

  Citation × Citation Citation Abstract Copy Title: Optimal irrigation management : a framework, model, and application for optimizing irrigation when supplies are limited Author: Hillyer, Charles C. (Charles Carter) Many regions in North America are experiencing water shortages, and these conditions are expected to worsen. The next generation of irrigation scheduling applications must therefore be capable of providing operational advice in support of deficit irrigation strategies. However, the theoretical, technical, and practical challenges associated with deficit irrigation scheduling are far more complex than conventional (full) irrigation. This dissertation presents three distinct systems for addressing the analytical challenges of deficit irrigation management. The first section of the dissertation presents a simulation framework for agro-ecological simulation. The objective was to develop a method to enable the assembly of simulation models from previously and independently developed component models. Based on a requirements analysis of existing simulation models we developed the ModCom simulation framework. ModCom provides a set of interface specifications that describe components in a simulation. ModCom also provides implementations of the core simulation services. The framework interfaces use well-defined binary standards and allows developers to implement the interfaces using a broad range of computer languages. The Second section describes the Irrigation Efficiency Model (IEM). IEM explicitly analyzes irrigation efficiency, accounts for spatial variability of soil properties and irrigation uniformity, performs simultaneous scheduling for all fields in the farm, accounts for energy use and its associated costs, and uses both ET and soil moisture measurements to enhance the accuracy of the irrigation schedules. IEM was developed specifically for implementing Deficit Irrigation and therefore includes analyses that go beyond the requirements of conventional irrigation scheduling. The third section describes Irrigation Management Online (IMO), a web application for optimum irrigation management. This system uses IEM to generate and deliver irrigation scheduling recommendations. IMO has been developed specifically to support irrigation management when either water supplies or delivery system capacities are limited. To mitigate the complexities of irrigation constraints the system has been designed so that the irrigation manager is an integral part of the irrigation optimization procedure. The final section outlines some of the key challenges that the next generation of schedulers must overcome in order to meet the needs of agricultural irrigation in an increasingly water short future. In addition, this section will discuss how irrigation advisory programs will need to operate differently in terms of what they do and how they do it. Title: Optimal irrigation management : a framework, model, and application for optimizing irrigation when supplies are limited Author: Hillyer, Charles C. (Charles Carter) Many regions in North America are experiencing water shortages, and these conditions are expected to worsen. The next generation of irrigation scheduling applications must therefore be capable of providing operational advice in support of deficit irrigation strategies. However, the theoretical, technical, and practical challenges associated with deficit irrigation scheduling are far more complex than conventional (full) irrigation. This dissertation presents three distinct systems for addressing the analytical challenges of deficit irrigation management. The first section of the dissertation presents a simulation framework for agro-ecological simulation. The objective was to develop a method to enable the assembly of simulation models from previously and independently developed component models. Based on a requirements analysis of existing simulation models we developed the ModCom simulation framework. ModCom provides a set of interface specifications that describe components in a simulation. ModCom also provides implementations of the core simulation services. The framework interfaces use well-defined binary standards and allows developers to implement the interfaces using a broad range of computer languages. The Second section describes the Irrigation Efficiency Model (IEM). IEM explicitly analyzes irrigation efficiency, accounts for spatial variability of soil properties and irrigation uniformity, performs simultaneous scheduling for all fields in the farm, accounts for energy use and its associated costs, and uses both ET and soil moisture measurements to enhance the accuracy of the irrigation schedules. IEM was developed specifically for implementing Deficit Irrigation and therefore includes analyses that go beyond the requirements of conventional irrigation scheduling. The third section describes Irrigation Management Online (IMO), a web application for optimum irrigation management. This system uses IEM to generate and deliver irrigation scheduling recommendations. IMO has been developed specifically to support irrigation management when either water supplies or delivery system capacities are limited. To mitigate the complexities of irrigation constraints the system has been designed so that the irrigation manager is an integral part of the irrigation optimization procedure. The final section outlines some of the key challenges that the next generation of schedulers must overcome in order to meet the needs of agricultural irrigation in an increasingly water short future. In addition, this section will discuss how irrigation advisory programs will need to operate differently in terms of what they do and how they do it. Close

• 2. [Article] Characterizing hydraulics and water distribution of furrow irrigation in northeast Malheur County

  Furrow irrigation is the dominant practice for irrigating row crops in the western Treasure Valley region near Ontario, Oregon. Though improvements have been made in management practices over the years, ...

  Citation × Citation Citation Abstract Copy Title: Characterizing hydraulics and water distribution of furrow irrigation in northeast Malheur County Author: Mittelstadt, Robert Furrow irrigation is the dominant practice for irrigating row crops in the western Treasure Valley region near Ontario, Oregon. Though improvements have been made in management practices over the years, excessive runoff and deep percolation are still important problems contributing to surface water and groundwater degradation. Field observations were made during two growing seasons to establish a data base from which the hydraulic surface irrigation model, SRFR (SRFR, a computer program for simulating flow in surface irrigation, developed at the U.S. Water Conservation Laboratory in Phoenix, Arizona (Strelkoff, 1991)), could be calibrated. SRFR is a numerical model, based on the principles of open channel hydraulics coupled with an empirical relationship characterizing furrow intake. SRFR is an analytical tool, with which the user supplies the physical parameters (such as furrow shape and furrow intake) and also the management variables (inflow rate and duration of inflow), and a simulation is conducted based on these conditions. Therefore, this model is a tool which provides insight into furrow irrigation processes. More specifically, SRFR can help answer such questions as which factors at the time of the irrigation are most important in determining irrigation performance. Once calibrated for a given set of conditions, various management strategies may be evaluated as to their relative effectiveness. These strategies may include, but are not limited to, cut-back irrigation, surge irrigation, alternating furrow irrigation, and laser-leveling of the field. A broad data-base is necessary for model calibration and to develop an understanding of it's limitations. Measurements of furrow intake, stream advance times, inflow and outflow, hydraulic roughness and furrow shape were obtained from several sites and irrigation events. These sites represent several crops, field lengths, field slopes, and soil textures. Using these data, a model calibration procedure was developed which matched irrigation inflow and outflow volumes and stream advance times for a given irrigation event. The calibration procedure is used to help identify those model input parameters that best describe a given irrigation event. This thesis is to provide a broad understanding of furrow irrigation systems in northeast Malheur County, recommended hydraulic parameters for use with SRFR, and the practical limitations of such hydraulic irrigation models. Irrigation performance is largely determined by the intake characteristics of the soil at the time of irrigation. Field conditions vary greatly depending on the crop, soil moisture, number of irrigations, tractor traffic, field slope, furrow shape and field history. The grower has control over only two variables which determine irrigation performance: inflow rate and duration. A difference in intake and irrigation performance was found to exist between non-wheel and wheel traffic furrows. These differences became less noticeable late in the season. Straw mulching greatly increases the furrow hydraulic roughness and therefore increases stream wetted perimeter and advance time. Vegetative interference from crops such as potato and sugar beets increase furrow hydraulic roughness late in the season. Initially, furrow shape depends on the crop and which cultivating implement is used. Furrow shape may evolve during the growing season depending on field slope, flow velocities, crop stand and the presence of crop residues and straw mulch. Title: Characterizing hydraulics and water distribution of furrow irrigation in northeast Malheur County Author: Mittelstadt, Robert Furrow irrigation is the dominant practice for irrigating row crops in the western Treasure Valley region near Ontario, Oregon. Though improvements have been made in management practices over the years, excessive runoff and deep percolation are still important problems contributing to surface water and groundwater degradation. Field observations were made during two growing seasons to establish a data base from which the hydraulic surface irrigation model, SRFR (SRFR, a computer program for simulating flow in surface irrigation, developed at the U.S. Water Conservation Laboratory in Phoenix, Arizona (Strelkoff, 1991)), could be calibrated. SRFR is a numerical model, based on the principles of open channel hydraulics coupled with an empirical relationship characterizing furrow intake. SRFR is an analytical tool, with which the user supplies the physical parameters (such as furrow shape and furrow intake) and also the management variables (inflow rate and duration of inflow), and a simulation is conducted based on these conditions. Therefore, this model is a tool which provides insight into furrow irrigation processes. More specifically, SRFR can help answer such questions as which factors at the time of the irrigation are most important in determining irrigation performance. Once calibrated for a given set of conditions, various management strategies may be evaluated as to their relative effectiveness. These strategies may include, but are not limited to, cut-back irrigation, surge irrigation, alternating furrow irrigation, and laser-leveling of the field. A broad data-base is necessary for model calibration and to develop an understanding of it's limitations. Measurements of furrow intake, stream advance times, inflow and outflow, hydraulic roughness and furrow shape were obtained from several sites and irrigation events. These sites represent several crops, field lengths, field slopes, and soil textures. Using these data, a model calibration procedure was developed which matched irrigation inflow and outflow volumes and stream advance times for a given irrigation event. The calibration procedure is used to help identify those model input parameters that best describe a given irrigation event. This thesis is to provide a broad understanding of furrow irrigation systems in northeast Malheur County, recommended hydraulic parameters for use with SRFR, and the practical limitations of such hydraulic irrigation models. Irrigation performance is largely determined by the intake characteristics of the soil at the time of irrigation. Field conditions vary greatly depending on the crop, soil moisture, number of irrigations, tractor traffic, field slope, furrow shape and field history. The grower has control over only two variables which determine irrigation performance: inflow rate and duration. A difference in intake and irrigation performance was found to exist between non-wheel and wheel traffic furrows. These differences became less noticeable late in the season. Straw mulching greatly increases the furrow hydraulic roughness and therefore increases stream wetted perimeter and advance time. Vegetative interference from crops such as potato and sugar beets increase furrow hydraulic roughness late in the season. Initially, furrow shape depends on the crop and which cultivating implement is used. Furrow shape may evolve during the growing season depending on field slope, flow velocities, crop stand and the presence of crop residues and straw mulch. Close

• 3. [Article] A computer model to simulate farm irrigation system energy requirements

  The development of the energy crisis has caused the use of depletable energy resources to be monitored quite closely in the United States. Within the agricultural sector, irrigation is a large user of ...

  Citation × Citation Citation Abstract Copy Title: A computer model to simulate farm irrigation system energy requirements Author: Kizer, Michael A. The development of the energy crisis has caused the use of depletable energy resources to be monitored quite closely in the United States. Within the agricultural sector, irrigation is a large user of energy, with the potential of using many times more energy than all other agricultural field operations. A better understanding of how energy is used by different irrigation systems could facilitate more efficient use of energy by one of the largest energy consumers in agriculture. This thesis attempts to realistically evaluate the total amount of non-renewable energy resources consumed in the irrigation process. Five portable and permanent sprinkler system types, plus trickle and gravity irrigation systems were studied. An evaluation of the energy required to manufacture the equipment, install it in the field, operate it, and transport it for an entire irrigation season was made. This evaluation was carried out in a variety of operating situations, with varying acreages, consumptive use rates, and total irrigation requirements. The paper begins by giving some background information about agriculture and irrigation as consumers of energy. A review of some of the research previously done which relates to energy use in irrigation is given. The evaluation of energy use by irrigation systems presented in this thesis were made with the use of a simulation model which was developed on the Oregon State University OS-3 Computer System. The model predicts energy requirements of an irrigation system by evaluating pumping energy requirements with basic hydraulic equations, the manufacturing energy requirements by calculating the required amounts of basic materials making up the system and the energy of manufacture of those basic materials. The energy for installation and the energy for transportation were evaluated by simulating methods of operation and management used in Oregon. The input parameters used in the modeling process. reproduce as closely as possible operating conditions encountered in Oregon. System types, component depreciation life, irrigation efficiencies and the range of irrigation requirements are ones that could typically be found in Oregon. For the situations considered, it was concluded that gravity irrigation required much less energy than other system types. The energy requirement for drip systems was about midway between the energy requirement for gravity systems and for sprinkler systems for most cases considered. The relative order of energy requirements for the various sprinkler systems was dependent upon the operating conditions considered. Title: A computer model to simulate farm irrigation system energy requirements Author: Kizer, Michael A. The development of the energy crisis has caused the use of depletable energy resources to be monitored quite closely in the United States. Within the agricultural sector, irrigation is a large user of energy, with the potential of using many times more energy than all other agricultural field operations. A better understanding of how energy is used by different irrigation systems could facilitate more efficient use of energy by one of the largest energy consumers in agriculture. This thesis attempts to realistically evaluate the total amount of non-renewable energy resources consumed in the irrigation process. Five portable and permanent sprinkler system types, plus trickle and gravity irrigation systems were studied. An evaluation of the energy required to manufacture the equipment, install it in the field, operate it, and transport it for an entire irrigation season was made. This evaluation was carried out in a variety of operating situations, with varying acreages, consumptive use rates, and total irrigation requirements. The paper begins by giving some background information about agriculture and irrigation as consumers of energy. A review of some of the research previously done which relates to energy use in irrigation is given. The evaluation of energy use by irrigation systems presented in this thesis were made with the use of a simulation model which was developed on the Oregon State University OS-3 Computer System. The model predicts energy requirements of an irrigation system by evaluating pumping energy requirements with basic hydraulic equations, the manufacturing energy requirements by calculating the required amounts of basic materials making up the system and the energy of manufacture of those basic materials. The energy for installation and the energy for transportation were evaluated by simulating methods of operation and management used in Oregon. The input parameters used in the modeling process. reproduce as closely as possible operating conditions encountered in Oregon. System types, component depreciation life, irrigation efficiencies and the range of irrigation requirements are ones that could typically be found in Oregon. For the situations considered, it was concluded that gravity irrigation required much less energy than other system types. The energy requirement for drip systems was about midway between the energy requirement for gravity systems and for sprinkler systems for most cases considered. The relative order of energy requirements for the various sprinkler systems was dependent upon the operating conditions considered. Close

• 4. [Article] Basin-wide distributed modeling of hydrologic responses to irrigation management in the Wood River Basin, Klamath County, OR

  The Wood River Basin lies upstream of Upper Klamath Lake, the main reservoir of the USBR Klamath Irrigation Project that provides irrigation water to 210,000 acres of downstream land. Water allocation ...

  Citation × Citation Citation Abstract Copy Title: Basin-wide distributed modeling of hydrologic responses to irrigation management in the Wood River Basin, Klamath County, OR Author: Owens, Joshua M. The Wood River Basin lies upstream of Upper Klamath Lake, the main reservoir of the USBR Klamath Irrigation Project that provides irrigation water to 210,000 acres of downstream land. Water allocation became a contentious issue in 2001 when drought led to curtailment of irrigation deliveries to the Klamath Irrigation Project in order to maintain minimum lake levels and river flows for endangered species. After lengthy negotiations the Klamath Basin Restoration Agreement was signed in February 2010, and calls for flow increases of 30,000 ac-ft/yr into Upper Klamath Lake from voluntary upstream sources. The Wood River Basin is a potential source of this water, but poorly understood hydrology makes estimates of water gains in response to conservation strategies uncertain. To better understand the hydrology of the Wood River Basin a fully distributed, physically based model was set up using the MIKE SHE hydrology model and MIKE 11 hydraulic model by DHI, Inc. The model was developed by recreating the actual management of the basin from 2002 to 2009, a period when tracts of land in the basin were enrolled in land idling programs for water conservation. Calibration and validation was evaluated against shallow groundwater observations. Overall the model described the average conditions of the basin well. Locations that were simulated inaccurately were limited to those in close proximity to the model boundary or to the Wood River, the result of using average values to describe these heterogeneous features. The model was used to simulate two end-member scenarios to determine the limits of water conservation strategies, basin-wide full irrigation and non-irrigation. Two reduced irrigation scenarios were also simulated, the first reduced the irrigation season to June and July, the second eliminated every other irrigation application. The simulation that recreated the actual management showed that non-irrigated tracts did not substantially reduce the consumptive use because water from the surrounding irrigated tracts was able to flow in via the shallow aquifer and provide sub-irrigation. For the full irrigation scenario the average annual consumptive use was 126,000 ac-ft/yr. For the non-irrigated scenario it was 96,000 ac-ft/yr, a reduction of 24%. For the two reduced irrigation scenarios the consumptive use was decreased by 14% and 12%. When compared to the irrigated scenario the total increase of flow to Upper Klamath Lake during the growing season was 60,000 ac-ft/yr for the non-irrigated scenario; and 36,000 ac-ft/yr and 31,000 ac-ft/yr for the two reduced irrigation scenarios respectively. Irrigation in the basin was found to transfer stream flow from the summer time to the winter time due to saturated winter conditions from late season irrigations resulting in increased runoff. There is potential for water conservation strategies in the Wood River Basin to substantially increase water flow into Upper Klamath Lake, but these strategies would have to be implemented extensively throughout the basin to reduce sub-irrigation. Title: Basin-wide distributed modeling of hydrologic responses to irrigation management in the Wood River Basin, Klamath County, OR Author: Owens, Joshua M. The Wood River Basin lies upstream of Upper Klamath Lake, the main reservoir of the USBR Klamath Irrigation Project that provides irrigation water to 210,000 acres of downstream land. Water allocation became a contentious issue in 2001 when drought led to curtailment of irrigation deliveries to the Klamath Irrigation Project in order to maintain minimum lake levels and river flows for endangered species. After lengthy negotiations the Klamath Basin Restoration Agreement was signed in February 2010, and calls for flow increases of 30,000 ac-ft/yr into Upper Klamath Lake from voluntary upstream sources. The Wood River Basin is a potential source of this water, but poorly understood hydrology makes estimates of water gains in response to conservation strategies uncertain. To better understand the hydrology of the Wood River Basin a fully distributed, physically based model was set up using the MIKE SHE hydrology model and MIKE 11 hydraulic model by DHI, Inc. The model was developed by recreating the actual management of the basin from 2002 to 2009, a period when tracts of land in the basin were enrolled in land idling programs for water conservation. Calibration and validation was evaluated against shallow groundwater observations. Overall the model described the average conditions of the basin well. Locations that were simulated inaccurately were limited to those in close proximity to the model boundary or to the Wood River, the result of using average values to describe these heterogeneous features. The model was used to simulate two end-member scenarios to determine the limits of water conservation strategies, basin-wide full irrigation and non-irrigation. Two reduced irrigation scenarios were also simulated, the first reduced the irrigation season to June and July, the second eliminated every other irrigation application. The simulation that recreated the actual management showed that non-irrigated tracts did not substantially reduce the consumptive use because water from the surrounding irrigated tracts was able to flow in via the shallow aquifer and provide sub-irrigation. For the full irrigation scenario the average annual consumptive use was 126,000 ac-ft/yr. For the non-irrigated scenario it was 96,000 ac-ft/yr, a reduction of 24%. For the two reduced irrigation scenarios the consumptive use was decreased by 14% and 12%. When compared to the irrigated scenario the total increase of flow to Upper Klamath Lake during the growing season was 60,000 ac-ft/yr for the non-irrigated scenario; and 36,000 ac-ft/yr and 31,000 ac-ft/yr for the two reduced irrigation scenarios respectively. Irrigation in the basin was found to transfer stream flow from the summer time to the winter time due to saturated winter conditions from late season irrigations resulting in increased runoff. There is potential for water conservation strategies in the Wood River Basin to substantially increase water flow into Upper Klamath Lake, but these strategies would have to be implemented extensively throughout the basin to reduce sub-irrigation. Close

• 5. [Article] Irrigation decision survey data for the Willamette Water 2100 project

  [suggested citation: "Jaeger, William K. (2016): Irrigation decision survey data for the Willamette Water 2100 project. OSU Libraries. Dataset. http://dx.doi.org/10.7267/N9H12ZXK"]

  Citation × Citation Citation Abstract Copy Title: Irrigation decision survey data for the Willamette Water 2100 project Author: Jaeger, William K. [suggested citation: "Jaeger, William K. (2016): Irrigation decision survey data for the Willamette Water 2100 project. OSU Libraries. Dataset. http://dx.doi.org/10.7267/N9H12ZXK"] Title: Irrigation decision survey data for the Willamette Water 2100 project Author: Jaeger, William K. [suggested citation: "Jaeger, William K. (2016): Irrigation decision survey data for the Willamette Water 2100 project. OSU Libraries. Dataset. http://dx.doi.org/10.7267/N9H12ZXK"] Close

• 6. [Article] Spring irrigation management of perennial ryegrass (Lolium perenne L.) seed production

  Introduction of later maturing cultivars of perennial ryegrass (Lolium perenne L.) places more seed production fields in a period of drought common to Oregon during vital stages of reproductive development. ...

  Citation × Citation Citation Abstract Copy Title: Spring irrigation management of perennial ryegrass (Lolium perenne L.) seed production Author: King, Craig Millhouser Introduction of later maturing cultivars of perennial ryegrass (Lolium perenne L.) places more seed production fields in a period of drought common to Oregon during vital stages of reproductive development. During these stages, the final yield of the crop is largely determined by the number of seeds set, and the development of individual seed weight. There is belief that water deficit during these periods may drastically reduce yield, which could be eliminated with properly timed spring irrigation. Therefore, this study was undertaken to (i) determine crop water use and water use efficiency of both irrigated and non-irrigated perennial ryegrass cultivars, (ii) observe any water use differences as a result of cultivar differences in perennial ryegrass, (iii) compare seed yield and seed yield components of different cultivars within irrigated and non-irrigated treatments, and (iv) determine appropriate timing and amount of irrigation to apply if it is revealed that irrigation enhances yield. A linear irrigation system was used to apply irrigation to six cultivars of perennial ryegrass in the crop years 2003 and 2004. In 2003 from 1 March to 25 July, 285 mm of water was consumed by non-irrigated plants, 365 mm when soil profile was filled once prior to peak anthesis, and 388 mm when soil moisture was maintained within 50 mm of field capacity to peak anthesis. In 2004 from 1 March to 8 July, nonirrigated plants consumed 279 mm of water, 353 mm from treatment to fill soil profile once, and 482 mm from treatment that maintained soil moisture up to peak anthesis. No statistical difference was observed in water use efficiency between treatments in 2003. In 2004 an interaction was observed between cultivars and irrigation, thus cultivars responded differently to irrigation. Contrasts revealed that cultivars responded differently with respect to water use efficiency. In 2003, irrigation to maintain soil moisture resulted in a 27% increase in yield, 18% due to an increase in seed number, and 8% due to an increase in seed weight. Irrigation to fill profile once resulted in a 21% increase in yield, 14% due to an increase in seed number, and 6% due to an increase in seed weight. In 2004 a cultivar by irrigation interaction was observed for total yield, seed weight, and seed number. Seed yield was increased by irrigation in all cultivars. In 2003, irrigation to maintain soil moisture began 3 June and corresponded with the beginning of anthesis, and proceeded to peak anthesis, 11 June. No rainfall was received during this period, or the period of seed fill which followed. In 2004 irrigation to maintain soil moisture began 29 April, and continued to peak anthesis, 4 June. Irrigation to fill profile once occurred between 3 June and 7 June in 2003, and between 31 May and 4 June in 2004. In 2004 significant rainfall occurred after peak anthesis during the period of seed fill. Data from both years suggest that irrigation to alleviate water deficit from the onset of anthesis through peak anthesis provides the plant with sufficient water to increase individual seed weight and seed set, thus improving overall yield. Title: Spring irrigation management of perennial ryegrass (Lolium perenne L.) seed production Author: King, Craig Millhouser Introduction of later maturing cultivars of perennial ryegrass (Lolium perenne L.) places more seed production fields in a period of drought common to Oregon during vital stages of reproductive development. During these stages, the final yield of the crop is largely determined by the number of seeds set, and the development of individual seed weight. There is belief that water deficit during these periods may drastically reduce yield, which could be eliminated with properly timed spring irrigation. Therefore, this study was undertaken to (i) determine crop water use and water use efficiency of both irrigated and non-irrigated perennial ryegrass cultivars, (ii) observe any water use differences as a result of cultivar differences in perennial ryegrass, (iii) compare seed yield and seed yield components of different cultivars within irrigated and non-irrigated treatments, and (iv) determine appropriate timing and amount of irrigation to apply if it is revealed that irrigation enhances yield. A linear irrigation system was used to apply irrigation to six cultivars of perennial ryegrass in the crop years 2003 and 2004. In 2003 from 1 March to 25 July, 285 mm of water was consumed by non-irrigated plants, 365 mm when soil profile was filled once prior to peak anthesis, and 388 mm when soil moisture was maintained within 50 mm of field capacity to peak anthesis. In 2004 from 1 March to 8 July, nonirrigated plants consumed 279 mm of water, 353 mm from treatment to fill soil profile once, and 482 mm from treatment that maintained soil moisture up to peak anthesis. No statistical difference was observed in water use efficiency between treatments in 2003. In 2004 an interaction was observed between cultivars and irrigation, thus cultivars responded differently to irrigation. Contrasts revealed that cultivars responded differently with respect to water use efficiency. In 2003, irrigation to maintain soil moisture resulted in a 27% increase in yield, 18% due to an increase in seed number, and 8% due to an increase in seed weight. Irrigation to fill profile once resulted in a 21% increase in yield, 14% due to an increase in seed number, and 6% due to an increase in seed weight. In 2004 a cultivar by irrigation interaction was observed for total yield, seed weight, and seed number. Seed yield was increased by irrigation in all cultivars. In 2003, irrigation to maintain soil moisture began 3 June and corresponded with the beginning of anthesis, and proceeded to peak anthesis, 11 June. No rainfall was received during this period, or the period of seed fill which followed. In 2004 irrigation to maintain soil moisture began 29 April, and continued to peak anthesis, 4 June. Irrigation to fill profile once occurred between 3 June and 7 June in 2003, and between 31 May and 4 June in 2004. In 2004 significant rainfall occurred after peak anthesis during the period of seed fill. Data from both years suggest that irrigation to alleviate water deficit from the onset of anthesis through peak anthesis provides the plant with sufficient water to increase individual seed weight and seed set, thus improving overall yield. Close

• 7. [Article] Drip vs. furrow irrigation in the delivery of Escherichia coli to onions

  This is the publisher’s final pdf. The published article is copyrighted by the American Society of Agricultural and Biological Engineers and can be found at: https://elibrary.asabe.org/toc_landing.asp?...

  Citation × Citation Citation Abstract Copy Title: Drip vs. furrow irrigation in the delivery of Escherichia coli to onions Author: Shock, C. C., Kreeft, H., Roncarati, R. A., Reitz, S. R., Klauzer, J. C., Shock, B. M. This is the publisher’s final pdf. The published article is copyrighted by the American Society of Agricultural and Biological Engineers and can be found at: https://elibrary.asabe.org/toc_landing.asp?conf=aeaj Title: Drip vs. furrow irrigation in the delivery of Escherichia coli to onions Author: Shock, C. C., Kreeft, H., Roncarati, R. A., Reitz, S. R., Klauzer, J. C., Shock, B. M. This is the publisher’s final pdf. The published article is copyrighted by the American Society of Agricultural and Biological Engineers and can be found at: https://elibrary.asabe.org/toc_landing.asp?conf=aeaj Close

• 8. [Article] Effects of irrigation frequency on yields of winter wheat

  Deliberately underirrigating a crop may yield economic benefits. The optimal use of water by an irrigator should be achieved under a deficit irrigation regime. It is important to know how water deficits ...

  Citation × Citation Citation Abstract Copy Title: Effects of irrigation frequency on yields of winter wheat Author: Nakamura, Brian Clifford Deliberately underirrigating a crop may yield economic benefits. The optimal use of water by an irrigator should be achieved under a deficit irrigation regime. It is important to know how water deficits affect yields and the interaction of the deficits with the scheduling of irrigations. A field experiment was conducted during the 1981 irrigation season to investigate the effects of high and low frequency deficit irrigation on yields of winter wheat. Yield and water use data were used to construct three production functions. The relationship between the level of water use and the resulting yield were determined for three irrigation frequency regimes. Field plots under daily (high frequency), weekly (normal frequency), and stress (reduced frequency) regimes were included in the field experiment as well as two dryland production plots. The relationships derived from this project were characterized by a large degree of scatter in the results. Highly favorable weather conditions offset the effects of irrigation deficits on plant yields throughout the irrigation season. At this time, a second year of data is in the process of compilation. The results of a regression analysis showed no statistically significant difference in the water use-yield relationships of the three irrigation frequency regimes. The effect of frequency did not lead to any readily apparent differences in the three production functions. The efficiency of water use of the different irrigation frequencies increases with decreasing amount of applied water for the 1981 crop year. The most efficient treatment, i.e., least water use per unit of yield, was the pre-plant irrigated, dryfarmed plots. The density of the wheat, a measure of crop quality also increased with decreased water use in this experiment. The optimal irrigation treatment (measured by production and quality) was the two-week frequency set. Title: Effects of irrigation frequency on yields of winter wheat Author: Nakamura, Brian Clifford Deliberately underirrigating a crop may yield economic benefits. The optimal use of water by an irrigator should be achieved under a deficit irrigation regime. It is important to know how water deficits affect yields and the interaction of the deficits with the scheduling of irrigations. A field experiment was conducted during the 1981 irrigation season to investigate the effects of high and low frequency deficit irrigation on yields of winter wheat. Yield and water use data were used to construct three production functions. The relationship between the level of water use and the resulting yield were determined for three irrigation frequency regimes. Field plots under daily (high frequency), weekly (normal frequency), and stress (reduced frequency) regimes were included in the field experiment as well as two dryland production plots. The relationships derived from this project were characterized by a large degree of scatter in the results. Highly favorable weather conditions offset the effects of irrigation deficits on plant yields throughout the irrigation season. At this time, a second year of data is in the process of compilation. The results of a regression analysis showed no statistically significant difference in the water use-yield relationships of the three irrigation frequency regimes. The effect of frequency did not lead to any readily apparent differences in the three production functions. The efficiency of water use of the different irrigation frequencies increases with decreasing amount of applied water for the 1981 crop year. The most efficient treatment, i.e., least water use per unit of yield, was the pre-plant irrigated, dryfarmed plots. The density of the wheat, a measure of crop quality also increased with decreased water use in this experiment. The optimal irrigation treatment (measured by production and quality) was the two-week frequency set. Close

• 9. [Article] Towards autonomous irrigation : comparison of two moisture sensing technologies, irrigation distribution analysis, and wireless network performance at an ornamental container nursery

  As ornamental container nurseries face diminishing water allocations, many are looking to automated irrigation solutions to increase their water application efficiency. This thesis presents the findings ...

  Citation × Citation Citation Abstract Copy Title: Towards autonomous irrigation : comparison of two moisture sensing technologies, irrigation distribution analysis, and wireless network performance at an ornamental container nursery Author: Bailey, Daniel R. (Daniel Roger) As ornamental container nurseries face diminishing water allocations, many are looking to automated irrigation solutions to increase their water application efficiency. This thesis presents the findings of a study conducted at a commercial container nursery to determine 1) whether a capacitance or load cell sensor was better suited for monitoring volumetric water content in the substrate; 2) if the actual irrigation distribution conformed to the expected pattern, how uniform were the weights of plants, and how these combined with plant canopy affected the leaching fraction; and 3) the reliability of the wireless network used to transmit the data to a central database. It was found that 1) the load cells outperformed the capacitance-based sensors because the load cells took an integrated measure; 2) the actual irrigation pattern followed the expected pattern, the variation of irrigation sections were low (C.V. = 0.06) and similar (C.V. ranging from 0.029 to 0.12), and unpruned plant canopies produced greater leaching fraction than pruned canopies (P < 0.18); and 3) wireless network transmission reliability was low (75.2%), suggesting that the system was not suitable for real-time irrigation control, but was sufficient for calculating irrigation length and monitoring net effective irrigation application and evapotranspirative consumption. Title: Towards autonomous irrigation : comparison of two moisture sensing technologies, irrigation distribution analysis, and wireless network performance at an ornamental container nursery Author: Bailey, Daniel R. (Daniel Roger) As ornamental container nurseries face diminishing water allocations, many are looking to automated irrigation solutions to increase their water application efficiency. This thesis presents the findings of a study conducted at a commercial container nursery to determine 1) whether a capacitance or load cell sensor was better suited for monitoring volumetric water content in the substrate; 2) if the actual irrigation distribution conformed to the expected pattern, how uniform were the weights of plants, and how these combined with plant canopy affected the leaching fraction; and 3) the reliability of the wireless network used to transmit the data to a central database. It was found that 1) the load cells outperformed the capacitance-based sensors because the load cells took an integrated measure; 2) the actual irrigation pattern followed the expected pattern, the variation of irrigation sections were low (C.V. = 0.06) and similar (C.V. ranging from 0.029 to 0.12), and unpruned plant canopies produced greater leaching fraction than pruned canopies (P < 0.18); and 3) wireless network transmission reliability was low (75.2%), suggesting that the system was not suitable for real-time irrigation control, but was sufficient for calculating irrigation length and monitoring net effective irrigation application and evapotranspirative consumption. Close

• 10. [Article] The effects of farm and operator characteristics, knowledge, and attitudes on farm-level improvements in irrigation efficiency in the central Willamette Valley

  A study was conducted using data collected from a sample of mint and vegetable farmers in the Willamette Valley of Oregon. The study identifies the influence of demographic differences, economic factors ...

  Citation × Citation Citation Abstract Copy Title: The effects of farm and operator characteristics, knowledge, and attitudes on farm-level improvements in irrigation efficiency in the central Willamette Valley Author: Stoff, Mary Cora A study was conducted using data collected from a sample of mint and vegetable farmers in the Willamette Valley of Oregon. The study identifies the influence of demographic differences, economic factors and irrigator attitudes on irrigation efficiency. Only two of the 19 characteristics theorized to influence irrigation efficiency proved to be statistically significant in both of two models. These significant variables, crop type (CROP), soil type (SOIL) suggest that a farmer's irrigation efficiency is unaffected by personal characteristics or attitudes. According to these results, the irrigator apparently applied the water that she deemed necessary, a decision based solely on the needs of the crop and the water-holding capacity of the soil. Title: The effects of farm and operator characteristics, knowledge, and attitudes on farm-level improvements in irrigation efficiency in the central Willamette Valley Author: Stoff, Mary Cora A study was conducted using data collected from a sample of mint and vegetable farmers in the Willamette Valley of Oregon. The study identifies the influence of demographic differences, economic factors and irrigator attitudes on irrigation efficiency. Only two of the 19 characteristics theorized to influence irrigation efficiency proved to be statistically significant in both of two models. These significant variables, crop type (CROP), soil type (SOIL) suggest that a farmer's irrigation efficiency is unaffected by personal characteristics or attitudes. According to these results, the irrigator apparently applied the water that she deemed necessary, a decision based solely on the needs of the crop and the water-holding capacity of the soil. Close

• 11. [Article] Irrigation choices for major West Coast crops : water scarcity and climatic determinants

  Recent climate change forecasts have aroused growing interest in the influence of water scarcity and climate on agricultural production and irrigation practice. However, it is common in the economic literature ...

  Citation × Citation Citation Abstract Copy Title: Irrigation choices for major West Coast crops : water scarcity and climatic determinants Author: Olen, Beau Recent climate change forecasts have aroused growing interest in the influence of water scarcity and climate on agricultural production and irrigation practice. However, it is common in the economic literature to aggregate disparate crops when modeling irrigation choices. That approach confounds the crop-specific effects of climate and water scarcity that govern such choices. Given the sensitivity of agricultural production to water scarcity and climate, understanding their influence on irrigation choices is a key contribution to policy evaluation. This paper addresses the impact of water scarcity and climate on irrigation choices through estimated models of cropland proportion irrigated (PI), and crop-specific irrigation technology choice (TC) and water application rates (AR). This approach is applied to agricultural production data for major crops (orchard/vineyard, vegetable, wheat, alfalfa, hay, and pasture) on the West Coast (California, Oregon, and Washington). Crop-specific modeling provides information about the distributional impacts of agricultural policy and climate change. This advantage is particularly important for the diverse agricultural landscape of the West Coast, where the distributional impacts of policy can be complex. The most important policy implications that are found involve asset heterogeneity and the distributional impacts of agricultural policy. Several findings provide valuable information about how irrigators would respond and adapt to climate change. The current findings also lead to commonly advocated revisions to federal water subsidy policies. Some key differences between the irrigation choices of higher- and lower-value crops are also identified. Identifying these differences sheds further light on the distributional consequences of agricultural policy. Many findings from this research are crop-specific and will have a high degree of policy relevance to irrigation districts or other agricultural jurisdictions that cultivate some of the West Coast's major crops. Furthermore, the data used in this research has a large degree of variation in water scarcity and climate, making the findings applicable to other Mediterranean climates in the world. It is found that specific crops have a proclivity for certain irrigation technologies that can mitigate particular climatic stressors (i.e., frost damage and heat stress). For example, the results indicate that water pricing policies will tend not to encourage water conservation by technology adoption for many orchards, vineyards, and vegetable farms, thereby imposing pure costs to these producers. In essence, climate heterogeneity limits options available to farmers and reduces the set of production technologies that a farm can use. This finding exemplifies that with climate heterogeneity, the distribution of water policy impacts depends on prior land allocation decisions such as crop choices. Heterogeneity in land quality is also found to have important influences on TC. The effects of temperature on irrigation choices are found to be more profound than the effects of precipitation. Because of the large study region used, the effects of temperature and precipitation on irrigation choices are often found to be quadratic-like. These quadratic-like relationships reveal thresholds where irrigators begin to respond very differently to climate. However, this was not the case for all crops. Thus, it is demonstrated that the effects of climate on irrigation choices are crop-dependent. The results indicate that for several crops, the discontinuance of irrigation water (i.e., water supply or price uncertainty) creates an option value that delays and discourages adoption of water-saving technologies. The discontinuance of irrigation water is also shown to reduce water demand at the farm-level extensive proportion (i.e., PI) and crop-level intensive margin (i.e., AR). Water price is found to impact all three irrigation choices as well. Well depth is found to facilitate adoption of water-saving technologies for several crops. This paper demonstrates that irrigation choices are highly dependent on water scarcity and climate. Institutional arrangements, geographic qualities of the farm, and demographic characteristics of the farmer also exhibit important influences on irrigation choices. By using crop-specific equations, quadratic climate variables, and a study region with large variation in climate conditions, this research resolves many inconsistent findings regarding the determinants of irrigation choices. Furthermore, this study establishes a research agenda for crop-specific analysis of irrigation choices. Some of the estimated results warrant verification with further studies. Future crop-specific irrigation choice studies would benefit from panel micro data with improved land quality variables, and seasonal or monthly climate variables that are better able to identify the effects of climate stress (e.g., heat stress and frost damage) on irrigation choices. Title: Irrigation choices for major West Coast crops : water scarcity and climatic determinants Author: Olen, Beau Recent climate change forecasts have aroused growing interest in the influence of water scarcity and climate on agricultural production and irrigation practice. However, it is common in the economic literature to aggregate disparate crops when modeling irrigation choices. That approach confounds the crop-specific effects of climate and water scarcity that govern such choices. Given the sensitivity of agricultural production to water scarcity and climate, understanding their influence on irrigation choices is a key contribution to policy evaluation. This paper addresses the impact of water scarcity and climate on irrigation choices through estimated models of cropland proportion irrigated (PI), and crop-specific irrigation technology choice (TC) and water application rates (AR). This approach is applied to agricultural production data for major crops (orchard/vineyard, vegetable, wheat, alfalfa, hay, and pasture) on the West Coast (California, Oregon, and Washington). Crop-specific modeling provides information about the distributional impacts of agricultural policy and climate change. This advantage is particularly important for the diverse agricultural landscape of the West Coast, where the distributional impacts of policy can be complex. The most important policy implications that are found involve asset heterogeneity and the distributional impacts of agricultural policy. Several findings provide valuable information about how irrigators would respond and adapt to climate change. The current findings also lead to commonly advocated revisions to federal water subsidy policies. Some key differences between the irrigation choices of higher- and lower-value crops are also identified. Identifying these differences sheds further light on the distributional consequences of agricultural policy. Many findings from this research are crop-specific and will have a high degree of policy relevance to irrigation districts or other agricultural jurisdictions that cultivate some of the West Coast's major crops. Furthermore, the data used in this research has a large degree of variation in water scarcity and climate, making the findings applicable to other Mediterranean climates in the world. It is found that specific crops have a proclivity for certain irrigation technologies that can mitigate particular climatic stressors (i.e., frost damage and heat stress). For example, the results indicate that water pricing policies will tend not to encourage water conservation by technology adoption for many orchards, vineyards, and vegetable farms, thereby imposing pure costs to these producers. In essence, climate heterogeneity limits options available to farmers and reduces the set of production technologies that a farm can use. This finding exemplifies that with climate heterogeneity, the distribution of water policy impacts depends on prior land allocation decisions such as crop choices. Heterogeneity in land quality is also found to have important influences on TC. The effects of temperature on irrigation choices are found to be more profound than the effects of precipitation. Because of the large study region used, the effects of temperature and precipitation on irrigation choices are often found to be quadratic-like. These quadratic-like relationships reveal thresholds where irrigators begin to respond very differently to climate. However, this was not the case for all crops. Thus, it is demonstrated that the effects of climate on irrigation choices are crop-dependent. The results indicate that for several crops, the discontinuance of irrigation water (i.e., water supply or price uncertainty) creates an option value that delays and discourages adoption of water-saving technologies. The discontinuance of irrigation water is also shown to reduce water demand at the farm-level extensive proportion (i.e., PI) and crop-level intensive margin (i.e., AR). Water price is found to impact all three irrigation choices as well. Well depth is found to facilitate adoption of water-saving technologies for several crops. This paper demonstrates that irrigation choices are highly dependent on water scarcity and climate. Institutional arrangements, geographic qualities of the farm, and demographic characteristics of the farmer also exhibit important influences on irrigation choices. By using crop-specific equations, quadratic climate variables, and a study region with large variation in climate conditions, this research resolves many inconsistent findings regarding the determinants of irrigation choices. Furthermore, this study establishes a research agenda for crop-specific analysis of irrigation choices. Some of the estimated results warrant verification with further studies. Future crop-specific irrigation choice studies would benefit from panel micro data with improved land quality variables, and seasonal or monthly climate variables that are better able to identify the effects of climate stress (e.g., heat stress and frost damage) on irrigation choices. Close

• 12. [Article] Irrigation to Enhance Native Seed Production for Great Basin Restoration

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Natural ...

  Citation × Citation Citation Abstract Copy Title: Irrigation to Enhance Native Seed Production for Great Basin Restoration Author: Shaw, Nancy L., Shock, Myrtle P., Saunders, Lamont D., Shock, Clinton C., Feibert, Erik B. G. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Natural Areas Association and can be found at: https://naturalareas.org/journal. Title: Irrigation to Enhance Native Seed Production for Great Basin Restoration Author: Shaw, Nancy L., Shock, Myrtle P., Saunders, Lamont D., Shock, Clinton C., Feibert, Erik B. G. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Natural Areas Association and can be found at: https://naturalareas.org/journal. Close

• 13. [Article] Addressing Data Resolution in Precision Agriculture

  Irrigated agriculture constitutes the greatest consumptive water use globally, so that irrigation efficiency measures are an important part of global efforts to best utilize this limited resource. However, ...

  Citation × Citation Citation Abstract Copy Title: Addressing Data Resolution in Precision Agriculture Author: Kelley, Jason Irrigated agriculture constitutes the greatest consumptive water use globally, so that irrigation efficiency measures are an important part of global efforts to best utilize this limited resource. However, greater irrigation efficiency must be achieved while simultaneously maintaining or increasing crop yields and farming profitability. Incremental water use decisions are made at the local level by farmers under many real world constraints; consequently they face significant risks in operating large and complex irrigation systems. These decisions should be supported by reliable information upon which to base operational plans and irrigation scheduling. Implementing precision irrigation effectively depends upon highly resolved estimates of crop water demand so that application rates match demand precisely both in location and timing. A fundamental challenge in mapping the irrigation requirement is addressing the heterogeneity of soil, biophysical, and atmospheric processes which mediate water demand. However, existing methods to determine the irrigation requirement assume that field conditions are homogeneous. Precision irrigation systems may enable more specific water distribution than traditional irrigation equipment, but allocating the correct amount of water requires crop water estimates that accurately reflect the variability of the irrigation requirement and consider the scale and timing at which irrigation can be delivered. This dissertation synthesizes the results from field studies which analyzed spatial patterns of irrigation performance and crop water demand under real field conditions. The first experiment quantified the performance of a precision irrigation system and determined the data resolution required for effective utilization of the system’s capability (Chapter 2). Field trials were conducted with a variable rate center pivot sprinkler (VRI) under normal farming conditions to determine this spatial resolution. The result was the definition of a performance coefficient and characteristic length scale associated with the irrigation system. The characteristic length scale describes the highest resolution prescription possible with VRI. Following on these findings, a second study compares an electromagnetic (EM) soil mapping method using extensive laboratory soil characterization as a basis for comparison (Chapter 3). The motivation of the study was to validate the EM method’s capability to detect small scale variations in soil water holding capacity, and to determine under which conditions the EM method can obtain reliable and robust soil maps. The findings reinforce earlier work on the importance of instrument calibration, and also show that specific soil characteristics may preclude using EM methods to map soil in some regions. Following the soil mapping study, further studies investigated methods to measure crop evapotranspiration (ET). A literature review was conducted to establish a catalog of contemporary methods to monitor ET, focusing on those commonly used in agriculture (Chapter 4). From this review, the surface renewal method (SR) emerged as potentially able to map ET feasibly and cost-effectively. Four field experiments were conducted over two years under a range of field conditions to establish a robust protocol for the determination of surface fluxes with SR (Chapter 5). Three of these experiments specifically investigated the potential for SR to be implemented from a moving sensor platform, such as an unmanned aerial vehicle. Experiments showed SR could estimate sensible heat flux as accurately as eddy covariance during moving trials. However, analysis of the minimum flux averaging period demonstrated that SR cannot resolve fluxes at the requisite spatial scales for precision irrigation. Nonetheless, SR remains promising for other practical applications in measuring surface fluxes. Future research questions and potential applications are explored in Chapters 5 and 6. The methods described here are directly relevant to water managers at the levels of farms and irrigation districts. Efficient irrigation planning depends on timely, reliable, and site-specific information in order to anticipate crop water demand, irrigate adequately to prevent drought stress, and maximize yield from the available resource. Growers and irrigation specialists currently have many resources at their disposal, including regional and satellite based ET estimates, state and local soil mapping, and scientific irrigation planning software. However, these methods do not provide site-specific and real time measurements of actual crop water demand, and farmers do not have any reliable means by which to validate the accuracy and precision of these estimates. For this information to be directly useful in irrigation planning, it should be validated by on site measurements. Reliable, local, and real time information is required to realize the full potential of precision agriculture. Title: Addressing Data Resolution in Precision Agriculture Author: Kelley, Jason Irrigated agriculture constitutes the greatest consumptive water use globally, so that irrigation efficiency measures are an important part of global efforts to best utilize this limited resource. However, greater irrigation efficiency must be achieved while simultaneously maintaining or increasing crop yields and farming profitability. Incremental water use decisions are made at the local level by farmers under many real world constraints; consequently they face significant risks in operating large and complex irrigation systems. These decisions should be supported by reliable information upon which to base operational plans and irrigation scheduling. Implementing precision irrigation effectively depends upon highly resolved estimates of crop water demand so that application rates match demand precisely both in location and timing. A fundamental challenge in mapping the irrigation requirement is addressing the heterogeneity of soil, biophysical, and atmospheric processes which mediate water demand. However, existing methods to determine the irrigation requirement assume that field conditions are homogeneous. Precision irrigation systems may enable more specific water distribution than traditional irrigation equipment, but allocating the correct amount of water requires crop water estimates that accurately reflect the variability of the irrigation requirement and consider the scale and timing at which irrigation can be delivered. This dissertation synthesizes the results from field studies which analyzed spatial patterns of irrigation performance and crop water demand under real field conditions. The first experiment quantified the performance of a precision irrigation system and determined the data resolution required for effective utilization of the system’s capability (Chapter 2). Field trials were conducted with a variable rate center pivot sprinkler (VRI) under normal farming conditions to determine this spatial resolution. The result was the definition of a performance coefficient and characteristic length scale associated with the irrigation system. The characteristic length scale describes the highest resolution prescription possible with VRI. Following on these findings, a second study compares an electromagnetic (EM) soil mapping method using extensive laboratory soil characterization as a basis for comparison (Chapter 3). The motivation of the study was to validate the EM method’s capability to detect small scale variations in soil water holding capacity, and to determine under which conditions the EM method can obtain reliable and robust soil maps. The findings reinforce earlier work on the importance of instrument calibration, and also show that specific soil characteristics may preclude using EM methods to map soil in some regions. Following the soil mapping study, further studies investigated methods to measure crop evapotranspiration (ET). A literature review was conducted to establish a catalog of contemporary methods to monitor ET, focusing on those commonly used in agriculture (Chapter 4). From this review, the surface renewal method (SR) emerged as potentially able to map ET feasibly and cost-effectively. Four field experiments were conducted over two years under a range of field conditions to establish a robust protocol for the determination of surface fluxes with SR (Chapter 5). Three of these experiments specifically investigated the potential for SR to be implemented from a moving sensor platform, such as an unmanned aerial vehicle. Experiments showed SR could estimate sensible heat flux as accurately as eddy covariance during moving trials. However, analysis of the minimum flux averaging period demonstrated that SR cannot resolve fluxes at the requisite spatial scales for precision irrigation. Nonetheless, SR remains promising for other practical applications in measuring surface fluxes. Future research questions and potential applications are explored in Chapters 5 and 6. The methods described here are directly relevant to water managers at the levels of farms and irrigation districts. Efficient irrigation planning depends on timely, reliable, and site-specific information in order to anticipate crop water demand, irrigate adequately to prevent drought stress, and maximize yield from the available resource. Growers and irrigation specialists currently have many resources at their disposal, including regional and satellite based ET estimates, state and local soil mapping, and scientific irrigation planning software. However, these methods do not provide site-specific and real time measurements of actual crop water demand, and farmers do not have any reliable means by which to validate the accuracy and precision of these estimates. For this information to be directly useful in irrigation planning, it should be validated by on site measurements. Reliable, local, and real time information is required to realize the full potential of precision agriculture. Close

• 14. [Article] Identification of irrigation practices using photographic and optical-mechanical scanning remote sensing techniques

  Irrigation is essential for profitable agriculture in the western United States. It is the largest consumer of water and power in Oregon. Conflicting uses of water and power and their scarcity demands judicious ...

  Citation × Citation Citation Abstract Copy Title: Identification of irrigation practices using photographic and optical-mechanical scanning remote sensing techniques Author: Naim, Shamim Irrigation is essential for profitable agriculture in the western United States. It is the largest consumer of water and power in Oregon. Conflicting uses of water and power and their scarcity demands judicious planning for allocation of these resources. Creditable baseline data are not only needed for irrigated crop acreages, but also for irrigation methods as an indicator of amount of water and power used. A data-gathering system is needed which is quick, reliable and comparatively inexpensive. The primary objective of this research was to develop a methodology to use remotely sensed data for irrigation method identification. The main tasks were to: (1) analyze multidate images for different emulsions and scales to identify irrigation methods: (2) develop mission parameters; (3) develop an image interpretation key; (4) investigate the feasibility of using a quantitative approach to irrigation method identification. The North Unit Deschutes Irrigation District of central Oregon was selected to develop and test the methodology. Field layout of different irrigation methods, their association with crops, soils, and slopes were noted for the area imaged by three CIR aerial flights during the 1979 growing season. A detailed crop calendar showing different phenological stages that affect the spectral properties of crops was developed. Images used for analysis included: Landsat MSS color transparencies at 1:1,000,000 for June 4, June 22, July 18, 1979; Landsat MSS color prints at 1:250,000 for May 17, and June 22, 1979; Landsat RBV images at 1:125,000 for June 8, 1978 and July 28, 1979; U-2 CIR photographs at 1:30,000 for June 28, 1973 and at 1:130,000 for August 2, 1978; CIR aerial photographs for May 12, July 9, and August 5, 1979 at 1:30,000 and 1:23,000. Two methods of analysis were used. Manual interpretation of the images employed light tables, magnifiers and stereomicroscope. Each test field along the flight line was carefully studied for detection of irrigation patterns using associated tones, colors, textures, and their temporal variations, in addition to crop calendar data, soil, and slope maps, ground information gathered, and black and white images at 1:8,000. Digital analysis of the data for discrimination of irrigated and non-irrigated crop types was discouraging as the data were for the late growing season (July 28, 1979), when most crops were either harvested or in the senescing stage and their spectral signatures overlapped. Conclusions drawn from this study are that: image-oriented analysis rather than quantitative analysis is best suited for irrigation method discrimination; CIR images provide better discrimination than black and white images; while irrigated and non-irrigated crops can be discriminated using multidate 1:1,000,000 images, for satisfactory discrimination of all irrigation methods, 1:30,000 or larger imagery is needed; and the best time for differentiating irrigation methods is the early growing season. As a result of this research, optimum mission parameters for flying photographic missions were developed and an image interpretation key useful for irrigation methods discrimination was developed. Title: Identification of irrigation practices using photographic and optical-mechanical scanning remote sensing techniques Author: Naim, Shamim Irrigation is essential for profitable agriculture in the western United States. It is the largest consumer of water and power in Oregon. Conflicting uses of water and power and their scarcity demands judicious planning for allocation of these resources. Creditable baseline data are not only needed for irrigated crop acreages, but also for irrigation methods as an indicator of amount of water and power used. A data-gathering system is needed which is quick, reliable and comparatively inexpensive. The primary objective of this research was to develop a methodology to use remotely sensed data for irrigation method identification. The main tasks were to: (1) analyze multidate images for different emulsions and scales to identify irrigation methods: (2) develop mission parameters; (3) develop an image interpretation key; (4) investigate the feasibility of using a quantitative approach to irrigation method identification. The North Unit Deschutes Irrigation District of central Oregon was selected to develop and test the methodology. Field layout of different irrigation methods, their association with crops, soils, and slopes were noted for the area imaged by three CIR aerial flights during the 1979 growing season. A detailed crop calendar showing different phenological stages that affect the spectral properties of crops was developed. Images used for analysis included: Landsat MSS color transparencies at 1:1,000,000 for June 4, June 22, July 18, 1979; Landsat MSS color prints at 1:250,000 for May 17, and June 22, 1979; Landsat RBV images at 1:125,000 for June 8, 1978 and July 28, 1979; U-2 CIR photographs at 1:30,000 for June 28, 1973 and at 1:130,000 for August 2, 1978; CIR aerial photographs for May 12, July 9, and August 5, 1979 at 1:30,000 and 1:23,000. Two methods of analysis were used. Manual interpretation of the images employed light tables, magnifiers and stereomicroscope. Each test field along the flight line was carefully studied for detection of irrigation patterns using associated tones, colors, textures, and their temporal variations, in addition to crop calendar data, soil, and slope maps, ground information gathered, and black and white images at 1:8,000. Digital analysis of the data for discrimination of irrigated and non-irrigated crop types was discouraging as the data were for the late growing season (July 28, 1979), when most crops were either harvested or in the senescing stage and their spectral signatures overlapped. Conclusions drawn from this study are that: image-oriented analysis rather than quantitative analysis is best suited for irrigation method discrimination; CIR images provide better discrimination than black and white images; while irrigated and non-irrigated crops can be discriminated using multidate 1:1,000,000 images, for satisfactory discrimination of all irrigation methods, 1:30,000 or larger imagery is needed; and the best time for differentiating irrigation methods is the early growing season. As a result of this research, optimum mission parameters for flying photographic missions were developed and an image interpretation key useful for irrigation methods discrimination was developed. Close

• 15. [Article] Orchard irrigation

  Citation × Citation Citation Abstract Copy Title: Orchard irrigation Author: Schrack, Claud, Currin, Harvey William Title: Orchard irrigation Author: Schrack, Claud, Currin, Harvey William Close

• 16. [Article] An irrigation efficiency model for optimum irrigation management

  Citation × Citation Citation Abstract Copy Title: An irrigation efficiency model for optimum irrigation management Author: Isbell, Brett, 1978- Title: An irrigation efficiency model for optimum irrigation management Author: Isbell, Brett, 1978- Close

• 17. [Article] Scale of operation on farms in a new irrigation district, Jefferson County, Oregon 1949-1953

  Citation × Citation Citation Abstract Copy Title: Scale of operation on farms in a new irrigation district, Jefferson County, Oregon 1949-1953 Author: Benedict, Russell Archie Title: Scale of operation on farms in a new irrigation district, Jefferson County, Oregon 1949-1953 Author: Benedict, Russell Archie Close

• 18. [Article] An investigation of alternative methods of valuing irrigation water

  Citation × Citation Citation Abstract Copy Title: An investigation of alternative methods of valuing irrigation water Author: Miller, Stanley F. Title: An investigation of alternative methods of valuing irrigation water Author: Miller, Stanley F. Close

• 19. [Article] An economic analysis of irrigation development in Nam Pong Irrigation Project, Khon Kaen, Thailand

  Citation × Citation Citation Abstract Copy Title: An economic analysis of irrigation development in Nam Pong Irrigation Project, Khon Kaen, Thailand Author: Sriswasdilek, Jerachone Title: An economic analysis of irrigation development in Nam Pong Irrigation Project, Khon Kaen, Thailand Author: Sriswasdilek, Jerachone Close

• 20. [Article] Economic optimization of irrigation

  Citation × Citation Citation Abstract Copy Title: Economic optimization of irrigation Author: English, Marshall J. Title: Economic optimization of irrigation Author: English, Marshall J. Close

• 21. [Article] Response of field corn to irrigation, plant population, and nitrogen on soils of the Willamette catena

  The purpose of this study was to make a preliminary investigation of the productivity of some of the soils within the Willamette catena under different systems of soil management. The study was carried ...

  Citation × Citation Citation Abstract Copy Title: Response of field corn to irrigation, plant population, and nitrogen on soils of the Willamette catena Author: Andersen, Jimmie Lee The purpose of this study was to make a preliminary investigation of the productivity of some of the soils within the Willamette catena under different systems of soil management. The study was carried out at four experimental sites near Corvallis, Oregon, during the 1962 growing season. The soil at each site was representative of a different soil series. The soil series were Willamette, Woodburn, Amity, and Dayton which are well-drained, moderately well drained, imperfectly drained, and poorly drained, respectively. Productivity was measured in terms of shelled corn yield. The eight treatments (systems of soil managements) were different combinations of irrigation, plant population, and nitrogen fertilization practices. The irrigation treatments were irrigated and non-irrigated. The Ievels of plant population were 9000, 14000, 18000, and 22000 plants per acre. The rates of nitrogen fertilization were 60 and 180 pounds of N per acre. A second objective of this study was to measure the response of field corn to each of the three soil management practices. Data pertaining to the effects of the three practices on shelling percentage and ear moisture at harvest, as well as grain yield, were collected. There were significant yield responses to irrigation when accompanied by higher levels of plant population at all sites. Generally, yield responses to higher levels of plant population and the higher rate of nitrogen fertilization were measured on the irrigated plots, but not on the non-irrigated plots. The shelling percentage on the irrigated plots was higher than that on the non-irrigated plots only at the Amity and Dayton sites. Apparently, plant population and nitrogen had no effect on shelling percentage. The amount of moisture in the ears at harvest was apparently not affected by irrigation, plant population, and nitrogen fertilization practices. In general, the productivities of the soils at the Willamette, Woodburn, and Amity sites were similar and significantly greater than at the Dayton site under all systems of soil management. Title: Response of field corn to irrigation, plant population, and nitrogen on soils of the Willamette catena Author: Andersen, Jimmie Lee The purpose of this study was to make a preliminary investigation of the productivity of some of the soils within the Willamette catena under different systems of soil management. The study was carried out at four experimental sites near Corvallis, Oregon, during the 1962 growing season. The soil at each site was representative of a different soil series. The soil series were Willamette, Woodburn, Amity, and Dayton which are well-drained, moderately well drained, imperfectly drained, and poorly drained, respectively. Productivity was measured in terms of shelled corn yield. The eight treatments (systems of soil managements) were different combinations of irrigation, plant population, and nitrogen fertilization practices. The irrigation treatments were irrigated and non-irrigated. The Ievels of plant population were 9000, 14000, 18000, and 22000 plants per acre. The rates of nitrogen fertilization were 60 and 180 pounds of N per acre. A second objective of this study was to measure the response of field corn to each of the three soil management practices. Data pertaining to the effects of the three practices on shelling percentage and ear moisture at harvest, as well as grain yield, were collected. There were significant yield responses to irrigation when accompanied by higher levels of plant population at all sites. Generally, yield responses to higher levels of plant population and the higher rate of nitrogen fertilization were measured on the irrigated plots, but not on the non-irrigated plots. The shelling percentage on the irrigated plots was higher than that on the non-irrigated plots only at the Amity and Dayton sites. Apparently, plant population and nitrogen had no effect on shelling percentage. The amount of moisture in the ears at harvest was apparently not affected by irrigation, plant population, and nitrogen fertilization practices. In general, the productivities of the soils at the Willamette, Woodburn, and Amity sites were similar and significantly greater than at the Dayton site under all systems of soil management. Close

• 22. [Article] Evaluation of erosion and sediment loss in furrow irrigation with alternative irrigation practices

  Citation × Citation Citation Abstract Copy Title: Evaluation of erosion and sediment loss in furrow irrigation with alternative irrigation practices Author: Tunio, Abdul Fatah Title: Evaluation of erosion and sediment loss in furrow irrigation with alternative irrigation practices Author: Tunio, Abdul Fatah Close

• 23. [Article] Deep well irrigation in Hamilton County, Nebraska : resource, development, impact and future

  Citation × Citation Citation Abstract Copy Title: Deep well irrigation in Hamilton County, Nebraska : resource, development, impact and future Author: Nelson, Charles Edward Title: Deep well irrigation in Hamilton County, Nebraska : resource, development, impact and future Author: Nelson, Charles Edward Close

• 24. [Article] Simple irrigation scheduling using the "look and feel" method

  Published August 1998. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catal...

  Citation × Citation Citation Abstract Copy Title: Simple irrigation scheduling using the "look and feel" method Author: Long, L. E. (Lynn Edwards), 1953-, Oregon State University. Extension Service, Niederholzer, Franz Published August 1998. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Simple irrigation scheduling using the "look and feel" method Author: Long, L. E. (Lynn Edwards), 1953-, Oregon State University. Extension Service, Niederholzer, Franz Published August 1998. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 25. [Article] Efficient lawn irrigation in the Intermountain West

  Published October 2010. Reviewed November 2014. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Efficient lawn irrigation in the Intermountain West Author: Charlton, Brian A., Cook, Thomas W., Golembiewski, Robert Craig, 1969-, Oregon State University. Extension Service Published October 2010. Reviewed November 2014. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Efficient lawn irrigation in the Intermountain West Author: Charlton, Brian A., Cook, Thomas W., Golembiewski, Robert Craig, 1969-, Oregon State University. Extension Service Published October 2010. Reviewed November 2014. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 26. [Article] Successful potato irrigation scheduling

  Published October 2006. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Successful potato irrigation scheduling Author: Pereira, Andre, Wang, Feng-Xin, Eldredge, Eric P., Flock, Rebecca, Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published October 2006. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Successful potato irrigation scheduling Author: Pereira, Andre, Wang, Feng-Xin, Eldredge, Eric P., Flock, Rebecca, Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published October 2006. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 27. [Article] Opportunity costs : irrigation vs. hydropower

  In recent years we have seen increasing debate over the allocation of PNW water resources. In particular there are conflicts over using the river system for irrigation vs. electricity production. Denying ...

  Citation × Citation Citation Abstract Copy Title: Opportunity costs : irrigation vs. hydropower Author: Ross, Mark In recent years we have seen increasing debate over the allocation of PNW water resources. In particular there are conflicts over using the river system for irrigation vs. electricity production. Denying the hydroelectric system water implies higher costs to electricity consumers as producers substitute more expensive nonhydro resources. This research looked at the impact of new irrigation on PNW electricity consumers. This was done under varying assumptions of demand response and farmer payments for pumping of irrigation water. The study also examined the difference between the current policy of allowing farmers to take all the water they need, and a policy in which withdrawals are limited in periods of low streamflow. Simulations were run to determine the amount of electricity production lost because of withdrawals. These results were then used in a series of simulations to estimate the economic impacts under the various assumptions and policies. It was found that irrigation caused losses to electricity consumers. In some cases this loss was on the order of $200/acre of irrigated land. The loss was significantly mitigated under the interruptible policy. Farmer payments for irrigation energy also reduced the loss to consumers. Title: Opportunity costs : irrigation vs. hydropower Author: Ross, Mark In recent years we have seen increasing debate over the allocation of PNW water resources. In particular there are conflicts over using the river system for irrigation vs. electricity production. Denying the hydroelectric system water implies higher costs to electricity consumers as producers substitute more expensive nonhydro resources. This research looked at the impact of new irrigation on PNW electricity consumers. This was done under varying assumptions of demand response and farmer payments for pumping of irrigation water. The study also examined the difference between the current policy of allowing farmers to take all the water they need, and a policy in which withdrawals are limited in periods of low streamflow. Simulations were run to determine the amount of electricity production lost because of withdrawals. These results were then used in a series of simulations to estimate the economic impacts under the various assumptions and policies. It was found that irrigation caused losses to electricity consumers. In some cases this loss was on the order of $200/acre of irrigated land. The loss was significantly mitigated under the interruptible policy. Farmer payments for irrigation energy also reduced the loss to consumers. Close

• 28. [Article] Hedonic price analysis to reveal value of water in irrigation : an application to northern Malheur County, Oregon

  Increasing water demand for growing municipalities, for water-based recreation and for fishery and wildlife habitat has intensified pressure on the existing resource. Reallocation of water from existing ...

  Citation × Citation Citation Abstract Copy Title: Hedonic price analysis to reveal value of water in irrigation : an application to northern Malheur County, Oregon Author: Faux, John Increasing water demand for growing municipalities, for water-based recreation and for fishery and wildlife habitat has intensified pressure on the existing resource. Reallocation of water from existing uses to other, higher-valued uses is receiving greater attention due to constraints on development of new water supplies. A key to reallocation is identification of the economic value associated with existing and alternative water uses. A hedonic price analysis of farm sales in eastern Oregon is performed to reveal the value of water used in irrigation. Estimation includes a joint test of heteroskedasticity and functional form. The value of water is shown to be strongly influenced by the crop-growing-capability of the soil on which it is applied. The value of an irrigated acre is not significantly influenced by the source of irrigation supply. The implicit market price of irrigation water in this area ranges from $44 per acre-foot (one-time delivery) on the best soils to $9 per acre-foot on the poorest soils irrigated. Title: Hedonic price analysis to reveal value of water in irrigation : an application to northern Malheur County, Oregon Author: Faux, John Increasing water demand for growing municipalities, for water-based recreation and for fishery and wildlife habitat has intensified pressure on the existing resource. Reallocation of water from existing uses to other, higher-valued uses is receiving greater attention due to constraints on development of new water supplies. A key to reallocation is identification of the economic value associated with existing and alternative water uses. A hedonic price analysis of farm sales in eastern Oregon is performed to reveal the value of water used in irrigation. Estimation includes a joint test of heteroskedasticity and functional form. The value of water is shown to be strongly influenced by the crop-growing-capability of the soil on which it is applied. The value of an irrigated acre is not significantly influenced by the source of irrigation supply. The implicit market price of irrigation water in this area ranges from $44 per acre-foot (one-time delivery) on the best soils to $9 per acre-foot on the poorest soils irrigated. Close

• 29. [Article] Linking GIS and a surface irrigation model to evaluate regional effects of furrow irrigation strategies

  The shallow aquifer in Northeast Malheur County, Oregon is polluted with Nitrates at concentrations exceeding federal drinking water standards. Efforts to solve the groundwater problems in this area have ...

  Citation × Citation Citation Abstract Copy Title: Linking GIS and a surface irrigation model to evaluate regional effects of furrow irrigation strategies Author: Faux, Russell N. The shallow aquifer in Northeast Malheur County, Oregon is polluted with Nitrates at concentrations exceeding federal drinking water standards. Efforts to solve the groundwater problems in this area have focused on developing farm management practices that will increase groundwater quality while maintaining agricultural production. Furrow irrigation is the dominant practice for irrigating row crops in this region. One potential way to improve water quality is to increase furrow irrigation performance on a regional scale. In this study a surface irrigation model, SRFR, was linked to a geographic information system (GIS) for the purpose of evaluating alternate furrow irrigation strategies in Malheur County, Oregon. SRFR is a physically based model that simulates water flow and distribution in irrigated furrows. The model accepts the management parameters that influence the outcome of an irrigation and in return provides measures of water application efficiency, amount of deep percolation, amount of surface run-off, and other performance indicators. The GIS, constructed using ARC/INFO software, contains the spatial data required to run SRFR on individual fields in the region. The data for the GIS were acquired using many different sources and techniques in order to meet the input resolution required by the irrigation model. The primary goal of this research was to develop a tool for evaluating irrigation practices on a regional scale, accounting for the diversity of physical circumstances and management practices that occur within a complex of several hundred farms. The particular application of this tool was for control of nitrate pollution of groundwater in the vicinity of Ontario, Oregon. The integrated system was used to estimate a base condition irrigation that is representative of current irrigation practices. The system was then used to assess irrigation performance using three alternative practices: 1) separate management of wheel and nonwheel compacted furrows; 2) use of an automated control system to vary application set times; and 3) cutback irrigation. Although this represents only a limited assessment of the alternatives that might be considered for the study area, preliminary results suggest that under certain field conditions irrigation efficiency can potentially improve more then 20% over the base condition using alternate strategies. The system demonstrated tremendous potential for identifying trends and variability in system performance in the region. Title: Linking GIS and a surface irrigation model to evaluate regional effects of furrow irrigation strategies Author: Faux, Russell N. The shallow aquifer in Northeast Malheur County, Oregon is polluted with Nitrates at concentrations exceeding federal drinking water standards. Efforts to solve the groundwater problems in this area have focused on developing farm management practices that will increase groundwater quality while maintaining agricultural production. Furrow irrigation is the dominant practice for irrigating row crops in this region. One potential way to improve water quality is to increase furrow irrigation performance on a regional scale. In this study a surface irrigation model, SRFR, was linked to a geographic information system (GIS) for the purpose of evaluating alternate furrow irrigation strategies in Malheur County, Oregon. SRFR is a physically based model that simulates water flow and distribution in irrigated furrows. The model accepts the management parameters that influence the outcome of an irrigation and in return provides measures of water application efficiency, amount of deep percolation, amount of surface run-off, and other performance indicators. The GIS, constructed using ARC/INFO software, contains the spatial data required to run SRFR on individual fields in the region. The data for the GIS were acquired using many different sources and techniques in order to meet the input resolution required by the irrigation model. The primary goal of this research was to develop a tool for evaluating irrigation practices on a regional scale, accounting for the diversity of physical circumstances and management practices that occur within a complex of several hundred farms. The particular application of this tool was for control of nitrate pollution of groundwater in the vicinity of Ontario, Oregon. The integrated system was used to estimate a base condition irrigation that is representative of current irrigation practices. The system was then used to assess irrigation performance using three alternative practices: 1) separate management of wheel and nonwheel compacted furrows; 2) use of an automated control system to vary application set times; and 3) cutback irrigation. Although this represents only a limited assessment of the alternatives that might be considered for the study area, preliminary results suggest that under certain field conditions irrigation efficiency can potentially improve more then 20% over the base condition using alternate strategies. The system demonstrated tremendous potential for identifying trends and variability in system performance in the region. Close

• 30. [Article] Successful onion irrigation scheduling

  Published September 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/cat...

  Citation × Citation Citation Abstract Copy Title: Successful onion irrigation scheduling Author: Klauzer, Jim, Feibert, Erik Bruno Goncalves, Oregon State University. Extension Service, Shock, C. C. (Clinton C.), Jensen, Lynn Published September 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Successful onion irrigation scheduling Author: Klauzer, Jim, Feibert, Erik Bruno Goncalves, Oregon State University. Extension Service, Shock, C. C. (Clinton C.), Jensen, Lynn Published September 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 31. [Article] Relationships between degree of ponding and uniformity of soil moisture distribution under irrigation sprinklers

  Often low intake rate soils need special consideration when applying water during an irrigation. Surface flooding for extended periods may cause adverse crop growth conditions. Properly designed sprinkler ...

  Citation × Citation Citation Abstract Copy Title: Relationships between degree of ponding and uniformity of soil moisture distribution under irrigation sprinklers Author: Dehlinger, Charles Robert Often low intake rate soils need special consideration when applying water during an irrigation. Surface flooding for extended periods may cause adverse crop growth conditions. Properly designed sprinkler systems often eliminate irrigation problems, because the application rate and quantity of water applied can be readily controlled. Research workers who have studied sprinkler irrigation disagree on many things. Differences are found in the literature concerning the procedures used to determine sprinkler distribution uniformity and the optimum rate of application of water to the soil. Several authors suggest that moisture movement within the soil occurs after an irrigation. If trans location of moisture occurs, it may be possible to use sprinkler system design specifications that are less critical than those now in use. In order to determine the effect of sprinkler application rate on the resulting soil moisture distribution it is necessary to have criteria relating degree of ponding, crop cover, and slope of the land to the uniformity of soil moisture. Experimental plots were designed and prepared to study and relate these factors to each other. Sprinkler distribution measurements were made to be used in computing sprinkler uniformity. Using neutron equipment, soil moisture determinations were made before the irrigation, one day after irrigation, and three days after irrigation to determine the effect of the irrigation. Final analysis of the data from the experiment indicated that there was not an optimum degree of ponding. In fact, ponding, application rate, grade of plots, and crop cover did not appear to appreciably affect the distribution of soil moisture after an irrigation. Title: Relationships between degree of ponding and uniformity of soil moisture distribution under irrigation sprinklers Author: Dehlinger, Charles Robert Often low intake rate soils need special consideration when applying water during an irrigation. Surface flooding for extended periods may cause adverse crop growth conditions. Properly designed sprinkler systems often eliminate irrigation problems, because the application rate and quantity of water applied can be readily controlled. Research workers who have studied sprinkler irrigation disagree on many things. Differences are found in the literature concerning the procedures used to determine sprinkler distribution uniformity and the optimum rate of application of water to the soil. Several authors suggest that moisture movement within the soil occurs after an irrigation. If trans location of moisture occurs, it may be possible to use sprinkler system design specifications that are less critical than those now in use. In order to determine the effect of sprinkler application rate on the resulting soil moisture distribution it is necessary to have criteria relating degree of ponding, crop cover, and slope of the land to the uniformity of soil moisture. Experimental plots were designed and prepared to study and relate these factors to each other. Sprinkler distribution measurements were made to be used in computing sprinkler uniformity. Using neutron equipment, soil moisture determinations were made before the irrigation, one day after irrigation, and three days after irrigation to determine the effect of the irrigation. Final analysis of the data from the experiment indicated that there was not an optimum degree of ponding. In fact, ponding, application rate, grade of plots, and crop cover did not appear to appreciably affect the distribution of soil moisture after an irrigation. Close

• 32. [Article] Transitional Effects of Double-lateral Drip Irrigation and Straw Mulch on Irrigation Water Consumption, Mineral Nutrition, Yield, and Storability of Sweet Cherry

  This is a scanned version of a published article. The original can be found at: http://horttech.ashspublications.org/. To the best of our knowledge, one or more authors of this paper were federal employees ...

  Citation × Citation Citation Abstract Copy Title: Transitional Effects of Double-lateral Drip Irrigation and Straw Mulch on Irrigation Water Consumption, Mineral Nutrition, Yield, and Storability of Sweet Cherry Author: le Roux, Jac, Bai, Jinhe, Yin, Xinhua, Huang, Xiao-Lan, Long, Lynn E., Seavert, Clark F., Jaja, Ngowari This is a scanned version of a published article. The original can be found at: http://horttech.ashspublications.org/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Transitional Effects of Double-lateral Drip Irrigation and Straw Mulch on Irrigation Water Consumption, Mineral Nutrition, Yield, and Storability of Sweet Cherry Author: le Roux, Jac, Bai, Jinhe, Yin, Xinhua, Huang, Xiao-Lan, Long, Lynn E., Seavert, Clark F., Jaja, Ngowari This is a scanned version of a published article. The original can be found at: http://horttech.ashspublications.org/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 33. [Article] Using infrared canopy temperature and leaf water potential for irrigation scheduling in peppermint (Mentha piperita L.)

  Several methods of infering plant water stress for irrigation scheduling are based upon measurements of the environment in which the plants grow. These measurements include parameters such as soil water ...

  Citation × Citation Citation Abstract Copy Title: Using infrared canopy temperature and leaf water potential for irrigation scheduling in peppermint (Mentha piperita L.) Author: Gallardo, Ivan T. Several methods of infering plant water stress for irrigation scheduling are based upon measurements of the environment in which the plants grow. These measurements include parameters such as soil water content, air temperature, pan evaporation and incident radiation. It is hypothesized that improved estimates of plant water deficit can be obtained by direct measurements made on the plants. The main objective of this study was to test the performance of measurements of canopy temperature and leaf water potential for irrigation scheduling. This study seeks to establish whether a correlation exists between these monitoring methods and measurements of soil moisture content, leaf area, and evapotranspiration. The experiments were conducted in first-year peppermint irrigated at five different rates. Canopy and air temperatures were measured with a hand-held infrared thermometer. Leaf water potential was measured with a pressure bomb. A non-stressed baseline for the difference between canopy temperature and air temperature using data from well-watered plants was used together with the vapor pressure deficit to determine the crop water stress index (CWSI). The results of this study show that the CWSI is well correlated to evapotranspiration deficit and is useful for irrigation scheduling. The relationship between leaf area yield and CWSI in peppermint was described by a quadratic function. Leaf water potential varied during the day in such a way that it was not possible to establish a relationship with water stress, differences in soil moisture content, or different irrigation levels. Leaf water potential was influenced by the daily weather conditions and represented the current demand more than the cumulative demand. The results of this study indicate that mid-day pressure bomb measurements cannot be used in irrigation scheduling. Predawn measurements of leaf water potential were stable, were well correlated with the different irrigation levels and soil moisture content, and therefore may be useful in irrigation scheduling. Title: Using infrared canopy temperature and leaf water potential for irrigation scheduling in peppermint (Mentha piperita L.) Author: Gallardo, Ivan T. Several methods of infering plant water stress for irrigation scheduling are based upon measurements of the environment in which the plants grow. These measurements include parameters such as soil water content, air temperature, pan evaporation and incident radiation. It is hypothesized that improved estimates of plant water deficit can be obtained by direct measurements made on the plants. The main objective of this study was to test the performance of measurements of canopy temperature and leaf water potential for irrigation scheduling. This study seeks to establish whether a correlation exists between these monitoring methods and measurements of soil moisture content, leaf area, and evapotranspiration. The experiments were conducted in first-year peppermint irrigated at five different rates. Canopy and air temperatures were measured with a hand-held infrared thermometer. Leaf water potential was measured with a pressure bomb. A non-stressed baseline for the difference between canopy temperature and air temperature using data from well-watered plants was used together with the vapor pressure deficit to determine the crop water stress index (CWSI). The results of this study show that the CWSI is well correlated to evapotranspiration deficit and is useful for irrigation scheduling. The relationship between leaf area yield and CWSI in peppermint was described by a quadratic function. Leaf water potential varied during the day in such a way that it was not possible to establish a relationship with water stress, differences in soil moisture content, or different irrigation levels. Leaf water potential was influenced by the daily weather conditions and represented the current demand more than the cumulative demand. The results of this study indicate that mid-day pressure bomb measurements cannot be used in irrigation scheduling. Predawn measurements of leaf water potential were stable, were well correlated with the different irrigation levels and soil moisture content, and therefore may be useful in irrigation scheduling. Close

• 34. [Article] Deficit Irrigation of Cabernet Sauvignon and Tempranillo: Impacts on Vine Growth, Yield, and Berry Composition

  Due to various reasons the previous investigator decided to pull out the crop level trials from the original experiment designed in 2010 season. However, the irrigation field experiments implemented in ...

  Citation × Citation Citation Abstract Copy Title: Deficit Irrigation of Cabernet Sauvignon and Tempranillo: Impacts on Vine Growth, Yield, and Berry Composition Author: Balint, Gabriel Due to various reasons the previous investigator decided to pull out the crop level trials from the original experiment designed in 2010 season. However, the irrigation field experiments implemented in the 2010 season continued in 2011, in order to find out the impact of varied deficit irrigation regimes on vine development and fruit composition in Tempranillo and Cabernet Sauvignon cultivars. Title: Deficit Irrigation of Cabernet Sauvignon and Tempranillo: Impacts on Vine Growth, Yield, and Berry Composition Author: Balint, Gabriel Due to various reasons the previous investigator decided to pull out the crop level trials from the original experiment designed in 2010 season. However, the irrigation field experiments implemented in the 2010 season continued in 2011, in order to find out the impact of varied deficit irrigation regimes on vine development and fruit composition in Tempranillo and Cabernet Sauvignon cultivars. Close

• 35. [Article] Evaluation of models for estimating surface irrigation infiltration parameters : data protocols and algorithm performance

  Citation × Citation Citation Abstract Copy Title: Evaluation of models for estimating surface irrigation infiltration parameters : data protocols and algorithm performance Author: Isbell, Sarah A. Title: Evaluation of models for estimating surface irrigation infiltration parameters : data protocols and algorithm performance Author: Isbell, Sarah A. Close

• 36. [Article] The value of irrigation water varies enormously across the Upper Klamath Basin

  Published January 2004. Reviewed January 2012. Please check for active titles in the OSU Extension Service website: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: The value of irrigation water varies enormously across the Upper Klamath Basin Author: Jaeger, William K. (William Kenneth), Oregon State University. Extension Service Published January 2004. Reviewed January 2012. Please check for active titles in the OSU Extension Service website: http://extension.oregonstate.edu/catalog Title: The value of irrigation water varies enormously across the Upper Klamath Basin Author: Jaeger, William K. (William Kenneth), Oregon State University. Extension Service Published January 2004. Reviewed January 2012. Please check for active titles in the OSU Extension Service website: http://extension.oregonstate.edu/catalog Close

• 37. [Article] Drip irrigation guide for potatoes in the Treasure Valley

  Published October 2006. Reviewed March 2012. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Drip irrigation guide for potatoes in the Treasure Valley Author: Flock, R., Pereira, A., Jensen, L., Eldredge, E., Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published October 2006. Reviewed March 2012. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Drip irrigation guide for potatoes in the Treasure Valley Author: Flock, R., Pereira, A., Jensen, L., Eldredge, E., Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published October 2006. Reviewed March 2012. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 38. [Article] Oregon crop water use and irrigation requirements

  Published June 1992. Reviewed July 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Oregon crop water use and irrigation requirements Author: Cuenca, Richard H., 1947-, Oregon State University. Extension Service Published June 1992. Reviewed July 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Oregon crop water use and irrigation requirements Author: Cuenca, Richard H., 1947-, Oregon State University. Extension Service Published June 1992. Reviewed July 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 39. [Article] Effect of irrigation level, insecticide and variety on root rot and yield of sweet corn: Research report to the Agricultural Research Foundation and the Oregon Processed Vegetable Commission, 2005

  Summary Irrigation effects on root rot and yield  Reducing irrigation during the first 6 weeks after planting reduced root rot of sweet corn at midseason and at harvest, consistent with findings of the ...

  Citation × Citation Citation Abstract Copy Title: Effect of irrigation level, insecticide and variety on root rot and yield of sweet corn: Research report to the Agricultural Research Foundation and the Oregon Processed Vegetable Commission, 2005 Author: Peachey, Ed Summary Irrigation effects on root rot and yield  Reducing irrigation during the first 6 weeks after planting reduced root rot of sweet corn at midseason and at harvest, consistent with findings of the past two years.  Reducing the early season irrigation level increased yield of Jubilee by 20% because of an increase in the number and size of ears produced. Insecticide effects  Vapam reduced midseason radicle root rot slightly.  The number of insect bites declined as the number of insecticides applied increased.  Insecticides had no effect on root rot at the Vegetable Research Farm, the site with greatest root rot levels. Insecticides may have increased root rot ratings at the Botany farm.  There was a positive but weak correlation (R=0.57) between insect damage to Jubilee roots and nodal root rot at the Vegetable Research Farm.  Insecticides may have increased yield of Coho (at both irrigation levels) and Jubilee (at the Low irrigation level) at the Vegetable Research Farm. Insecticides increased yield of all varieties in the Botany Farm experiment. Varietal effects  Yield of Coho was greater than Jubilee, Kokanee, and Chase at both sites. Coho yields were consistently High under stresses of root rot and insect damage. Title: Effect of irrigation level, insecticide and variety on root rot and yield of sweet corn: Research report to the Agricultural Research Foundation and the Oregon Processed Vegetable Commission, 2005 Author: Peachey, Ed Summary Irrigation effects on root rot and yield  Reducing irrigation during the first 6 weeks after planting reduced root rot of sweet corn at midseason and at harvest, consistent with findings of the past two years.  Reducing the early season irrigation level increased yield of Jubilee by 20% because of an increase in the number and size of ears produced. Insecticide effects  Vapam reduced midseason radicle root rot slightly.  The number of insect bites declined as the number of insecticides applied increased.  Insecticides had no effect on root rot at the Vegetable Research Farm, the site with greatest root rot levels. Insecticides may have increased root rot ratings at the Botany farm.  There was a positive but weak correlation (R=0.57) between insect damage to Jubilee roots and nodal root rot at the Vegetable Research Farm.  Insecticides may have increased yield of Coho (at both irrigation levels) and Jubilee (at the Low irrigation level) at the Vegetable Research Farm. Insecticides increased yield of all varieties in the Botany Farm experiment. Varietal effects  Yield of Coho was greater than Jubilee, Kokanee, and Chase at both sites. Coho yields were consistently High under stresses of root rot and insect damage. Close

• 40. [Article] Descriptive analysis of two consecutive vintages of Oregon Pinot noir wines as effected by irrigation, tillage and nitrogen supplementation in the vineyard

  Two vintages of Vitis vinifera cv. Pinot noir wine from a viticulture trial evaluating nitrogen fertilization, tilling and irrigation underwent descriptive analysis using a modified version of free-choice ...

  Citation × Citation Citation Abstract Copy Title: Descriptive analysis of two consecutive vintages of Oregon Pinot noir wines as effected by irrigation, tillage and nitrogen supplementation in the vineyard Author: Hjorth, Heather Byrne Two vintages of Vitis vinifera cv. Pinot noir wine from a viticulture trial evaluating nitrogen fertilization, tilling and irrigation underwent descriptive analysis using a modified version of free-choice profiling. Wines were made from three field blocks of the twelve factorial combinations of Irrigation (Dry or Irrigated), Tillage (Tilled or not Tilled) and Fertilization (None, Foliar nitrogen supplementation or soil applied nitrogen). Irrigation was associated with lower anthocyanins and total phenols as well as lower color intensity and purple hue in both vintages. Irrigation increased vegetative and spicy character in the 1999 vintage while non-irrigated treatments were characterized by fruit, cherry and berry characteristics. Tilling significantly increased fruity flavor and body in the 1999 vintage and was associated with increased vegetative character in the 2000 vintage. In the 2000 vintage, non-fertilized treatments were significantly higher in floral aroma than the soil or foliar fertilized treatments. Title: Descriptive analysis of two consecutive vintages of Oregon Pinot noir wines as effected by irrigation, tillage and nitrogen supplementation in the vineyard Author: Hjorth, Heather Byrne Two vintages of Vitis vinifera cv. Pinot noir wine from a viticulture trial evaluating nitrogen fertilization, tilling and irrigation underwent descriptive analysis using a modified version of free-choice profiling. Wines were made from three field blocks of the twelve factorial combinations of Irrigation (Dry or Irrigated), Tillage (Tilled or not Tilled) and Fertilization (None, Foliar nitrogen supplementation or soil applied nitrogen). Irrigation was associated with lower anthocyanins and total phenols as well as lower color intensity and purple hue in both vintages. Irrigation increased vegetative and spicy character in the 1999 vintage while non-irrigated treatments were characterized by fruit, cherry and berry characteristics. Tilling significantly increased fruity flavor and body in the 1999 vintage and was associated with increased vegetative character in the 2000 vintage. In the 2000 vintage, non-fertilized treatments were significantly higher in floral aroma than the soil or foliar fertilized treatments. Close

• 41. [Article] A farm-level economic analysis of water-conserving irrigation systems and commercial agricultural water transfers to instream flows in central Oregon

  The middle Deschutes River between Bend, Oregon and Lake Billy Chinook typically experiences critically low flows during the irrigation season. Commercial agriculture in the North Unit Irrigation District ...

  Citation × Citation Citation Abstract Copy Title: A farm-level economic analysis of water-conserving irrigation systems and commercial agricultural water transfers to instream flows in central Oregon Author: Turner, Brenda The middle Deschutes River between Bend, Oregon and Lake Billy Chinook typically experiences critically low flows during the irrigation season. Commercial agriculture in the North Unit Irrigation District and Central Oregon Irrigation District is one major user of Deschutes River water. The overall objective of this research was to estimate the cost to transfer water from commercial agriculture operations to instream flow use assuming a water market existed. Two methods of providing water within commercial agriculture were considered; 1) lining irrigation district canals that supply water to farms and 2) changing on-farm water use. On-farm practices include adopting water conserving irrigation technologies and involvement in Oregon's water conservation program. Supply curves were generated for these alternatives assuming expected and alternative streamfiow levels. Results indicated that changing crop rotations, adopting water conserving technologies and participating in Oregon's conservation program were used, depending on the market price for water. Canal lining, however, was generally the most cost-effective means of providing water to enhance flows in the middle Deschutes River. Title: A farm-level economic analysis of water-conserving irrigation systems and commercial agricultural water transfers to instream flows in central Oregon Author: Turner, Brenda The middle Deschutes River between Bend, Oregon and Lake Billy Chinook typically experiences critically low flows during the irrigation season. Commercial agriculture in the North Unit Irrigation District and Central Oregon Irrigation District is one major user of Deschutes River water. The overall objective of this research was to estimate the cost to transfer water from commercial agriculture operations to instream flow use assuming a water market existed. Two methods of providing water within commercial agriculture were considered; 1) lining irrigation district canals that supply water to farms and 2) changing on-farm water use. On-farm practices include adopting water conserving irrigation technologies and involvement in Oregon's water conservation program. Supply curves were generated for these alternatives assuming expected and alternative streamfiow levels. Results indicated that changing crop rotations, adopting water conserving technologies and participating in Oregon's conservation program were used, depending on the market price for water. Canal lining, however, was generally the most cost-effective means of providing water to enhance flows in the middle Deschutes River. Close

• 42. [Article] Effect of nitrogen fertilizer and irrigation on Acacia senegal seedling biomass and photosynthesis

  Seedlings of Acacia senegal were grown in a glass greenhouse to study the effect of nitrogen and irrigation regimes on dry matter production and allocation to different plant organs, net photosynthesis ...

  Citation × Citation Citation Abstract Copy Title: Effect of nitrogen fertilizer and irrigation on Acacia senegal seedling biomass and photosynthesis Author: Warrag, Esam Eldin I. Seedlings of Acacia senegal were grown in a glass greenhouse to study the effect of nitrogen and irrigation regimes on dry matter production and allocation to different plant organs, net photosynthesis per unit leaf area, and nitrogen content in the different plant organs. Ammonium nitrate (NH4NO3) was used in this study, as the source of inorganic nitrogen. The nitrogen treatment consisted of four levels: 0, 30, 100, and 200 ppm of N which were added with the irrigation solution. Irrigation treatment consisted of irrigation every two, five or ten days. Nitrogen fertilization, irrigation regimes, and their interaction significantly affect the total stem, root, and leaf dry weight. However, low and moderate levels of N with irrigation every two days, resulted in higher total plant dry weight. Contrary to the initial hypothesis of the study, net photosynthesis showed no significant differences among the N treatments, but a decrease occurred after the fifth day since irrigation; this was also followed by a low net CO2 uptake. Stomatal conductance was affected significantly by the N and irrigation treatments. Total N content in the whole seedlings, stems, roots, and leaves was found to be high at low to moderate application of N, with irrigation every two days, while percent N in these parts showed a marked increase with increasing the N added. Moreover, percent N in roots showed the highest increase compared to percent N in stems and leaves. Title: Effect of nitrogen fertilizer and irrigation on Acacia senegal seedling biomass and photosynthesis Author: Warrag, Esam Eldin I. Seedlings of Acacia senegal were grown in a glass greenhouse to study the effect of nitrogen and irrigation regimes on dry matter production and allocation to different plant organs, net photosynthesis per unit leaf area, and nitrogen content in the different plant organs. Ammonium nitrate (NH4NO3) was used in this study, as the source of inorganic nitrogen. The nitrogen treatment consisted of four levels: 0, 30, 100, and 200 ppm of N which were added with the irrigation solution. Irrigation treatment consisted of irrigation every two, five or ten days. Nitrogen fertilization, irrigation regimes, and their interaction significantly affect the total stem, root, and leaf dry weight. However, low and moderate levels of N with irrigation every two days, resulted in higher total plant dry weight. Contrary to the initial hypothesis of the study, net photosynthesis showed no significant differences among the N treatments, but a decrease occurred after the fifth day since irrigation; this was also followed by a low net CO2 uptake. Stomatal conductance was affected significantly by the N and irrigation treatments. Total N content in the whole seedlings, stems, roots, and leaves was found to be high at low to moderate application of N, with irrigation every two days, while percent N in these parts showed a marked increase with increasing the N added. Moreover, percent N in roots showed the highest increase compared to percent N in stems and leaves. Close

• 43. [Article] Shallow Aquifer Recharge from Irrigation in a Semi-arid Agricultural Valley in New Mexico, USA

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the American Society of Civil Engineers and can be found at: http://cedb.asce.o...

  Citation × Citation Citation Abstract Copy Title: Shallow Aquifer Recharge from Irrigation in a Semi-arid Agricultural Valley in New Mexico, USA Author: Ochoa, Carlos G., Shukla, Manoj K., Guldan, Steven J., Fernald, Alexander G., Tidwell, Vincent C. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the American Society of Civil Engineers and can be found at: http://cedb.asce.org/cgi/WWWdisplay.cgi?310565. Title: Shallow Aquifer Recharge from Irrigation in a Semi-arid Agricultural Valley in New Mexico, USA Author: Ochoa, Carlos G., Shukla, Manoj K., Guldan, Steven J., Fernald, Alexander G., Tidwell, Vincent C. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the American Society of Civil Engineers and can be found at: http://cedb.asce.org/cgi/WWWdisplay.cgi?310565. Close

• 44. [Article] Irrigation Frequency Alters Nutrient Uptake in Container-grown Rhododendron Plants Grown with Different Rates of Nitrogen

  The influence of irrigation frequency (same amount of water per day given at different times) on nutrient uptake of container-grown evergreen Rhododendron ‘P.J.M. Compact’ (PJM) and ‘English Roseum’ (ER) ...

  Citation × Citation Citation Abstract Copy Title: Irrigation Frequency Alters Nutrient Uptake in Container-grown Rhododendron Plants Grown with Different Rates of Nitrogen Author: Regan, Richard P., Bi, Guihong, Scagel, Carolyn F., Fuchigami, Leslie H. The influence of irrigation frequency (same amount of water per day given at different times) on nutrient uptake of container-grown evergreen Rhododendron ‘P.J.M. Compact’ (PJM) and ‘English Roseum’ (ER) and deciduous Rhododendron ‘Gibraltar’ (AZ) grown with different rates of nitrogen (N) fertilizer was evaluated. Increased N application rate increased nutrient uptake and plant dry biomass. Irrigation frequency did not significantly influence total plant dry biomass; however, more frequent irrigation decreased net uptake of several nutrients including phosphorus (P), boron (B), and manganese (Mn) uptake in all cultivars; potassium (K), copper (Cu), and zinc (Zn) uptake in AZ and ER; sulfur (S) uptake in ER and PJM; and iron (Fe) uptake in AZ. Additionally, more frequent irrigation of evergreen cultivars increased calcium (Ca) uptake. Covariate analyses were used to compare nutrient uptake among cultivars and irrigation treatments after accounting for the variability in nutrient uptake attributable to differences in biomass and N uptake. For most nutrients, the influence of irrigation frequency on uptake was partially attributable to differences in biomass and N uptake. After accounting for the variability in nutrient uptake associated with biomass or N uptake, increased irrigation frequency decreased P, S, B, Cu, and Mn uptake only in ER and increased Ca uptake in the two evergreen cultivars. Differences in nutrient uptake among cultivars in response to irrigation treatments were related to water and N availability during production and their combined influence on water stress, nutrient uptake, and biomass partitioning. Estimates of nutrient demand and uptake efficiency using nutrient concentrations and ratios are discussed in relation to nutrient management differences for different cultivars and irrigation treatments. Title: Irrigation Frequency Alters Nutrient Uptake in Container-grown Rhododendron Plants Grown with Different Rates of Nitrogen Author: Regan, Richard P., Bi, Guihong, Scagel, Carolyn F., Fuchigami, Leslie H. The influence of irrigation frequency (same amount of water per day given at different times) on nutrient uptake of container-grown evergreen Rhododendron ‘P.J.M. Compact’ (PJM) and ‘English Roseum’ (ER) and deciduous Rhododendron ‘Gibraltar’ (AZ) grown with different rates of nitrogen (N) fertilizer was evaluated. Increased N application rate increased nutrient uptake and plant dry biomass. Irrigation frequency did not significantly influence total plant dry biomass; however, more frequent irrigation decreased net uptake of several nutrients including phosphorus (P), boron (B), and manganese (Mn) uptake in all cultivars; potassium (K), copper (Cu), and zinc (Zn) uptake in AZ and ER; sulfur (S) uptake in ER and PJM; and iron (Fe) uptake in AZ. Additionally, more frequent irrigation of evergreen cultivars increased calcium (Ca) uptake. Covariate analyses were used to compare nutrient uptake among cultivars and irrigation treatments after accounting for the variability in nutrient uptake attributable to differences in biomass and N uptake. For most nutrients, the influence of irrigation frequency on uptake was partially attributable to differences in biomass and N uptake. After accounting for the variability in nutrient uptake associated with biomass or N uptake, increased irrigation frequency decreased P, S, B, Cu, and Mn uptake only in ER and increased Ca uptake in the two evergreen cultivars. Differences in nutrient uptake among cultivars in response to irrigation treatments were related to water and N availability during production and their combined influence on water stress, nutrient uptake, and biomass partitioning. Estimates of nutrient demand and uptake efficiency using nutrient concentrations and ratios are discussed in relation to nutrient management differences for different cultivars and irrigation treatments. Close

• 45. [Article] Irrigation Decisions for Major West Coast Crops: Water Scarcity and Climatic Determinants

  Access to this item has been restricted by repository administrators at the request of the publisher, Oxford University Press, until June 15, 2017.

  Citation × Citation Citation Abstract Copy Title: Irrigation Decisions for Major West Coast Crops: Water Scarcity and Climatic Determinants Author: Olen, Beau, Wu, JunJie, Langpap, Christian Access to this item has been restricted by repository administrators at the request of the publisher, Oxford University Press, until June 15, 2017. Title: Irrigation Decisions for Major West Coast Crops: Water Scarcity and Climatic Determinants Author: Olen, Beau, Wu, JunJie, Langpap, Christian Access to this item has been restricted by repository administrators at the request of the publisher, Oxford University Press, until June 15, 2017. Close

• 46. [Article] An Engineers Approach to Irrigation Management in Oregon Pinot noir

  Vineyard managers must decide on the timing and amount of irrigation. In Oregon the need for irrigation differs greatly year to year and field to field based on micro climate, soil, root development, plant ...

  Citation × Citation Citation Abstract Copy Title: An Engineers Approach to Irrigation Management in Oregon Pinot noir Author: Selker, John, Baer, Emilie Vineyard managers must decide on the timing and amount of irrigation. In Oregon the need for irrigation differs greatly year to year and field to field based on micro climate, soil, root development, plant health, and root stock. We suggest the use of leaf water potential as a useful management tool. We show that for this test to provide consistent values, leaves should be wrapped prior to removal, should have consistent solar exposure, but need not have precisely the same age. We illustrate the use of this measure with data from the 2001 growing season taken in two Willamette valley fields. The data showed that irrigation was not required throughout the season, and helps explain the unexpectedly high yields noted by the vineyards. Title: An Engineers Approach to Irrigation Management in Oregon Pinot noir Author: Selker, John, Baer, Emilie Vineyard managers must decide on the timing and amount of irrigation. In Oregon the need for irrigation differs greatly year to year and field to field based on micro climate, soil, root development, plant health, and root stock. We suggest the use of leaf water potential as a useful management tool. We show that for this test to provide consistent values, leaves should be wrapped prior to removal, should have consistent solar exposure, but need not have precisely the same age. We illustrate the use of this measure with data from the 2001 growing season taken in two Willamette valley fields. The data showed that irrigation was not required throughout the season, and helps explain the unexpectedly high yields noted by the vineyards. Close

• 47. [Article] Irrigating peppermint

  Declared out of print March 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate...

  Citation × Citation Citation Abstract Copy Title: Irrigating peppermint Author: Mitchell, Alan R., Oregon State University. Extension Service Declared out of print March 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Irrigating peppermint Author: Mitchell, Alan R., Oregon State University. Extension Service Declared out of print March 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 48. [Article] Strategies for efficient irrigation water use

  Published July 2001. Revised March 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Strategies for efficient irrigation water use Author: Shock, B. M., Oregon State University. Extension Service, Shock, C. C. (Clinton C.), Welch, Teresa Published July 2001. Revised March 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Strategies for efficient irrigation water use Author: Shock, B. M., Oregon State University. Extension Service, Shock, C. C. (Clinton C.), Welch, Teresa Published July 2001. Revised March 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 49. [Article] Drip irrigation guide for onion growers

  Published December 2005. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Drip irrigation guide for onion growers Author: Shock, Cedric A., Feibert, Erik Bruno Goncalves, Flock, Rebecca, Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published December 2005. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Drip irrigation guide for onion growers Author: Shock, Cedric A., Feibert, Erik Bruno Goncalves, Flock, Rebecca, Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published December 2005. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 50. [Article] Drip irrigation guide for growers of hybrid poplar

  Published December 2005. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Drip irrigation guide for growers of hybrid poplar Author: Pereira, Andre, O'Neill, Mick, Feibert, Erik Bruno Goncalves, Flock, Rebecca, Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published December 2005. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Drip irrigation guide for growers of hybrid poplar Author: Pereira, Andre, O'Neill, Mick, Feibert, Erik Bruno Goncalves, Flock, Rebecca, Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published December 2005. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 51. [Article] Irrigating deciduous fruit and nut trees in Oregon

  Declared out of print December 2009. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonst...

  Citation × Citation Citation Abstract Copy Title: Irrigating deciduous fruit and nut trees in Oregon Author: Rackham, Robert L., Oregon State University. Extension Service Declared out of print December 2009. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Irrigating deciduous fruit and nut trees in Oregon Author: Rackham, Robert L., Oregon State University. Extension Service Declared out of print December 2009. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 52. [Article] Report of the Special Committee of the United States Senate on the Irrigation and Reclamation of Arid Lands, Vols 1 and 2.

  Gerald W. Williams Collection. Issued also as Senate rept. 928, 51st Cong., 1st sess. [pt.I] Report of committee and Views of the minority. v.1. The Northwest. v.2. The Great Basin region and California. ...

  Citation × Citation Citation Abstract Copy Title: Report of the Special Committee of the United States Senate on the Irrigation and Reclamation of Arid Lands, Vols 1 and 2. Author: United States Congress. Senate Select Committee on the Irrigation and Reclamation of Arid Lands. Gerald W. Williams Collection. Issued also as Senate rept. 928, 51st Cong., 1st sess. [pt.I] Report of committee and Views of the minority. v.1. The Northwest. v.2. The Great Basin region and California. -- [pt.II] v.3. Rocky Mountain region and Great Plains. v.4. Statements by Director Powell and other officers of the U. S. Geological Survey. Consular reports. General report on irrigation in United States. Miscellaneous papers. [v.5] Irrigation in the United States. By R.J. Hinton... being a 2d ed. of Misc. doc. 15, 49th Cong. [2d sess.] Title: Report of the Special Committee of the United States Senate on the Irrigation and Reclamation of Arid Lands, Vols 1 and 2. Author: United States Congress. Senate Select Committee on the Irrigation and Reclamation of Arid Lands. Gerald W. Williams Collection. Issued also as Senate rept. 928, 51st Cong., 1st sess. [pt.I] Report of committee and Views of the minority. v.1. The Northwest. v.2. The Great Basin region and California. -- [pt.II] v.3. Rocky Mountain region and Great Plains. v.4. Statements by Director Powell and other officers of the U. S. Geological Survey. Consular reports. General report on irrigation in United States. Miscellaneous papers. [v.5] Irrigation in the United States. By R.J. Hinton... being a 2d ed. of Misc. doc. 15, 49th Cong. [2d sess.] Close

• 53. [Article] Water management in the North Deschutes unit irrigation district : geographic perspectives and remote sensing applications

  The North Unit irrigation District of Central Oregon, a water project developed under the guidelines of the Bureau of Reclamation, is characterized by limited water and the need for efficient utilization ...

  Citation × Citation Citation Abstract Copy Title: Water management in the North Deschutes unit irrigation district : geographic perspectives and remote sensing applications Author: Nellis, M. Duane The North Unit irrigation District of Central Oregon, a water project developed under the guidelines of the Bureau of Reclamation, is characterized by limited water and the need for efficient utilization and control of the irrigation system. To manage the limited water resource, irrigators need a timely and economical method of detecting problems associated with parameters of the irrigation water management system. The primary objective of this research was to determine the practicality of utilizing thermal infrared imagery and color infrared photography for assessing irrigation water management problems. Within this objective the key tasks were to: examine the relationship between the physical and cultural components that play an integral role in irrigation water management; determine the applications of remote sensing for detecting non-uniformity of water distribution over selected fields during three stages of crop growth; determine the applications of remote sensing for detecting crop response in relation to a diversity of field conditions; determine the application of remote sensing for analyzing conveyance system leakage sites; and examine possible techniques for maintaining proper irrigation water management. A field survey of the area covered by the overflights was used to map patterns of fields and irrigation methods. Additionally, maps showing soil series and percent slope were produced of the overflight coverage area. The survey and maps provided a valuable reference during interpretation of the imagery and photography to determine relationships between soils, topography, crop type, size and shape of fields, and irrigation methods employed. Information on cropping history, soil amendments, and irrigation scheduling strategies were obtained from case study farmers. Ground-based measurements were made in conjunction with overflights to determine field characteristics. This involved precise notation of weather conditions, soil parameters and crop characteristics of case study sites. The thermal infrared imagery (flown May 21, May 24, July 7, and September 7, 1979) and color infrared photography (flown May 12, July 9, and September 7, 1979) were analyzed with the aid of a stereomicroscope, film viewing light table, and digital image processor. Data gathered through farm interviews, ground-based measurements, and imagery and aerial photographic interpretation were statistically treated using the Statistical Package for the Social Sciences program at Oregon State University. The results of this research demonstrate the practicality of using thermal infrared imagery and color infrared photography for detecting problems associated with the irrigation water management system. The thermal infrared imagery was useful for detecting canal leakage, non-uniformity of water distribution at all stages of crop growth, and apparent crop canopy temperatures as an indicator of crop stress. The color infrared photography was useful for detecting crop stress resulting from a variety of field conditions. Field conditions detected on the photography and affecting crop health included physical parameters of the land resource base (soils, topography, and climate), the influence of irrigators through tillage practices, the affect of irrigation water applications, and the influence of applications of herbicides, pesticides, and fertilizers. Additionally, color infrared photography was used to determine the extent of unexpected system problems (e.g. flooding caused by a lateral canal plugging). Title: Water management in the North Deschutes unit irrigation district : geographic perspectives and remote sensing applications Author: Nellis, M. Duane The North Unit irrigation District of Central Oregon, a water project developed under the guidelines of the Bureau of Reclamation, is characterized by limited water and the need for efficient utilization and control of the irrigation system. To manage the limited water resource, irrigators need a timely and economical method of detecting problems associated with parameters of the irrigation water management system. The primary objective of this research was to determine the practicality of utilizing thermal infrared imagery and color infrared photography for assessing irrigation water management problems. Within this objective the key tasks were to: examine the relationship between the physical and cultural components that play an integral role in irrigation water management; determine the applications of remote sensing for detecting non-uniformity of water distribution over selected fields during three stages of crop growth; determine the applications of remote sensing for detecting crop response in relation to a diversity of field conditions; determine the application of remote sensing for analyzing conveyance system leakage sites; and examine possible techniques for maintaining proper irrigation water management. A field survey of the area covered by the overflights was used to map patterns of fields and irrigation methods. Additionally, maps showing soil series and percent slope were produced of the overflight coverage area. The survey and maps provided a valuable reference during interpretation of the imagery and photography to determine relationships between soils, topography, crop type, size and shape of fields, and irrigation methods employed. Information on cropping history, soil amendments, and irrigation scheduling strategies were obtained from case study farmers. Ground-based measurements were made in conjunction with overflights to determine field characteristics. This involved precise notation of weather conditions, soil parameters and crop characteristics of case study sites. The thermal infrared imagery (flown May 21, May 24, July 7, and September 7, 1979) and color infrared photography (flown May 12, July 9, and September 7, 1979) were analyzed with the aid of a stereomicroscope, film viewing light table, and digital image processor. Data gathered through farm interviews, ground-based measurements, and imagery and aerial photographic interpretation were statistically treated using the Statistical Package for the Social Sciences program at Oregon State University. The results of this research demonstrate the practicality of using thermal infrared imagery and color infrared photography for detecting problems associated with the irrigation water management system. The thermal infrared imagery was useful for detecting canal leakage, non-uniformity of water distribution at all stages of crop growth, and apparent crop canopy temperatures as an indicator of crop stress. The color infrared photography was useful for detecting crop stress resulting from a variety of field conditions. Field conditions detected on the photography and affecting crop health included physical parameters of the land resource base (soils, topography, and climate), the influence of irrigators through tillage practices, the affect of irrigation water applications, and the influence of applications of herbicides, pesticides, and fertilizers. Additionally, color infrared photography was used to determine the extent of unexpected system problems (e.g. flooding caused by a lateral canal plugging). Close

• 54. [Article] Establishing irrigation criteria for cultivation of Veratrum californicum

  Veratrum californicum (common name: corn lily) is a wild plant species that grows in the Intermountain West, its range extending from British Columbia to Mexico. Corn lily is of interest because it has ...

  Citation × Citation Citation Abstract Copy Title: Establishing irrigation criteria for cultivation of Veratrum californicum Author: Doniger, Alison R. Veratrum californicum (common name: corn lily) is a wild plant species that grows in the Intermountain West, its range extending from British Columbia to Mexico. Corn lily is of interest because it has the potential to provide pharmaceutical precursors for use in the treatment of cancer. Pharmaceutical companies are currently running clinical trials of new drugs that use these precursors. As such, a sustainable supply of corn lily is needed if these drugs are ever to enter the market. Unfortunately, wild populations of corn lily will not be able to meet the market demand. Therefore, it is necessary that horticultural guidelines be established so that corn lily can be grown in an agricultural setting. Establishing irrigation criteria is one crucial component in this process, as corn lily grows in naturally wet areas and will most likely require supplemental irrigation in an agricultural setting. In order to determine the appropriate level of irrigation for corn lily, an appropriate range of irrigation levels to test in a field trial must be determined. Plant success as a function of irrigation level can then be measured. In order to determine what irrigation levels should be tested, the OSU Malheur Experiment Station monitored the natural environment of corn lily at a variety of locations over the course of four seasons. Results showed that for the majority of its growing season, corn lily occupies a narrow environmental niche where soil water tension ranges from 0 kPa to 30 kPa. With this information, irrigation levels ranging from 5 kPa to 30 kPa were chosen for irrigation trials. In 2009, corn lily plots were established at Ontario, Oregon and McCall, Idaho. Irrigation trials were run in 2010, 2011, and 2012 at Ontario and McCall. Plots were assigned to five irrigation treatments: 5 kPa (added halfway through the 2010 growing season), 10 kPa, 15 kPa, 20 kPa, and 30 kPa. Collectively, the data indicate that the 5 and 10 kPa treatments are most conducive to corn lily survival and growth. In addition, the observed data are consistent with the hypothesis that soil moisture levels in the first month of growth may be the most important determinant in plant growth and survival. Title: Establishing irrigation criteria for cultivation of Veratrum californicum Author: Doniger, Alison R. Veratrum californicum (common name: corn lily) is a wild plant species that grows in the Intermountain West, its range extending from British Columbia to Mexico. Corn lily is of interest because it has the potential to provide pharmaceutical precursors for use in the treatment of cancer. Pharmaceutical companies are currently running clinical trials of new drugs that use these precursors. As such, a sustainable supply of corn lily is needed if these drugs are ever to enter the market. Unfortunately, wild populations of corn lily will not be able to meet the market demand. Therefore, it is necessary that horticultural guidelines be established so that corn lily can be grown in an agricultural setting. Establishing irrigation criteria is one crucial component in this process, as corn lily grows in naturally wet areas and will most likely require supplemental irrigation in an agricultural setting. In order to determine the appropriate level of irrigation for corn lily, an appropriate range of irrigation levels to test in a field trial must be determined. Plant success as a function of irrigation level can then be measured. In order to determine what irrigation levels should be tested, the OSU Malheur Experiment Station monitored the natural environment of corn lily at a variety of locations over the course of four seasons. Results showed that for the majority of its growing season, corn lily occupies a narrow environmental niche where soil water tension ranges from 0 kPa to 30 kPa. With this information, irrigation levels ranging from 5 kPa to 30 kPa were chosen for irrigation trials. In 2009, corn lily plots were established at Ontario, Oregon and McCall, Idaho. Irrigation trials were run in 2010, 2011, and 2012 at Ontario and McCall. Plots were assigned to five irrigation treatments: 5 kPa (added halfway through the 2010 growing season), 10 kPa, 15 kPa, 20 kPa, and 30 kPa. Collectively, the data indicate that the 5 and 10 kPa treatments are most conducive to corn lily survival and growth. In addition, the observed data are consistent with the hypothesis that soil moisture levels in the first month of growth may be the most important determinant in plant growth and survival. Close

• 55. [Article] Application of nonequilibrium ecology to managed riparian ecosystems

  Seasonal trends in water table level and soil moisture for four plant community types within an irrigated eastern Oregon riparian zone were described. Aboveground biomass, species composition, litter, ...

  Citation × Citation Citation Abstract Copy Title: Application of nonequilibrium ecology to managed riparian ecosystems Author: Stringham, Tamzen K. Seasonal trends in water table level and soil moisture for four plant community types within an irrigated eastern Oregon riparian zone were described. Aboveground biomass, species composition, litter, percent bareground and percent basal cover of key plant species and life forms were measured. The relationship between water table levels and soil moisture content were analyzed using simple linear regression. Transition zones between plant community types based on soil moisture and/or depth to water table during the growing season were determined. The soil moisture-water table relationship can be used to predict changes in plant community composition induced by a permanent depth to water table change. Irrigation impact on meadow water table levels and stream temperature were determined. Water table levels responded to irrigation manipulations within days. The permanent cessation of irrigation would shrink the riparian meadows contained within this study from widths in excess of 300 m to less than 60 m. Continuous stream temperature data were collected on a stream running through adjacent non-irrigated and irrigated meadows. Daily maximum stream temperatures in the segment contained within the irrigated meadow were 1.0° to 3.0° C cooler than the reach contained within the non-irrigated meadow. Management impact on plant community attributes, forage production and forage quality were assessed under three pasture management alternatives. Comparison of stubble height, litter, forage production, forage quality, species composition, percent bareground and percent basal cover of key plant species and life forms indicated all three management alternatives are sustainable from both a plant community and a livestock production perspective. Title: Application of nonequilibrium ecology to managed riparian ecosystems Author: Stringham, Tamzen K. Seasonal trends in water table level and soil moisture for four plant community types within an irrigated eastern Oregon riparian zone were described. Aboveground biomass, species composition, litter, percent bareground and percent basal cover of key plant species and life forms were measured. The relationship between water table levels and soil moisture content were analyzed using simple linear regression. Transition zones between plant community types based on soil moisture and/or depth to water table during the growing season were determined. The soil moisture-water table relationship can be used to predict changes in plant community composition induced by a permanent depth to water table change. Irrigation impact on meadow water table levels and stream temperature were determined. Water table levels responded to irrigation manipulations within days. The permanent cessation of irrigation would shrink the riparian meadows contained within this study from widths in excess of 300 m to less than 60 m. Continuous stream temperature data were collected on a stream running through adjacent non-irrigated and irrigated meadows. Daily maximum stream temperatures in the segment contained within the irrigated meadow were 1.0° to 3.0° C cooler than the reach contained within the non-irrigated meadow. Management impact on plant community attributes, forage production and forage quality were assessed under three pasture management alternatives. Comparison of stubble height, litter, forage production, forage quality, species composition, percent bareground and percent basal cover of key plant species and life forms indicated all three management alternatives are sustainable from both a plant community and a livestock production perspective. Close

• 56. [Article] Risk/return analysis of irrigation system design and operating rules

  A model was developed to simulate winter wheat production on irrigated farmland similar to that found near Hermiston, Oregon. The simulated farm is irrigated with a side roll sprinkler system. A well is ...

  Citation × Citation Citation Abstract Copy Title: Risk/return analysis of irrigation system design and operating rules Author: Nielsen, Kim C. A model was developed to simulate winter wheat production on irrigated farmland similar to that found near Hermiston, Oregon. The simulated farm is irrigated with a side roll sprinkler system. A well is located adjacent to the wheat field and the water is delivered by an electrically powered pump. The major components of the model are: 1. The soil moisture component which estimates daily soil moisture level. The soil moisture level is a function of daily precipitation, daily irrigation and daily evapotranspiration. Evapotranspiration is calculated as a function of measured pan evaporation, wheat plant stage of development and the soil moisture level. 2. The irrigation component which schedules daily irrigation based on the decision strategies supplied by the model user. There are three major parts of each strategy, the irrigation system design, the set time in hours and the soil moisture level that initiates irrigation. 3. The yield component of the model which estimates wheat grain yield as a function of daily temperature, daily soil moisture, and stage of plant growth. The scheduling of irrigation will create variability in the soil moisture level across the field. This variability of soil moisture is incorporated in the yield component. 4. The risk/returns component which calculates the net returns and utility. Utility is equal to the average net return minus the standard deviation weighted by a risk aversion factor. Wheat production was simulated for 19 years of daily weather data from the Hermiston Agricultural Experiment Station from 1963-1981. Several strategies were compared. The comparisons were made of the yields, water use, irrigation costs, net returns, risk and utility of the various strategies. The strategies were ranked according to maximum utility. The results indicated that designing irrigation systems for maximum yields did not result in the highest utility. The optimum strategies were those that initiated irrigation at a low level of soil moisture depletion and used a system with a relatively lower capital investment. The average annualized investment cost f or the five strategies with the highest yields was $76.43 per acre. The annualized investment cost for the five strategies with the highest utility was $57.54 per acre. The difference in average utility between the two groups was $19.37 per acre. The strategy with the highest yield had a utility level of $295.77 per acre. The strategy with the highest utility had a utility level of $337.12 per acre. The analysis included only those costs associated with irrigation. Utility was more sensitive to labor costs and water charges than to the cost of energy and interest rates. The level of risk aversion made very little difference in the relative level of utility for the different strategies. If the moisture holding capacity of the soil was reduced then the level of risk aversion made a bigger difference in the relative level of utility. Title: Risk/return analysis of irrigation system design and operating rules Author: Nielsen, Kim C. A model was developed to simulate winter wheat production on irrigated farmland similar to that found near Hermiston, Oregon. The simulated farm is irrigated with a side roll sprinkler system. A well is located adjacent to the wheat field and the water is delivered by an electrically powered pump. The major components of the model are: 1. The soil moisture component which estimates daily soil moisture level. The soil moisture level is a function of daily precipitation, daily irrigation and daily evapotranspiration. Evapotranspiration is calculated as a function of measured pan evaporation, wheat plant stage of development and the soil moisture level. 2. The irrigation component which schedules daily irrigation based on the decision strategies supplied by the model user. There are three major parts of each strategy, the irrigation system design, the set time in hours and the soil moisture level that initiates irrigation. 3. The yield component of the model which estimates wheat grain yield as a function of daily temperature, daily soil moisture, and stage of plant growth. The scheduling of irrigation will create variability in the soil moisture level across the field. This variability of soil moisture is incorporated in the yield component. 4. The risk/returns component which calculates the net returns and utility. Utility is equal to the average net return minus the standard deviation weighted by a risk aversion factor. Wheat production was simulated for 19 years of daily weather data from the Hermiston Agricultural Experiment Station from 1963-1981. Several strategies were compared. The comparisons were made of the yields, water use, irrigation costs, net returns, risk and utility of the various strategies. The strategies were ranked according to maximum utility. The results indicated that designing irrigation systems for maximum yields did not result in the highest utility. The optimum strategies were those that initiated irrigation at a low level of soil moisture depletion and used a system with a relatively lower capital investment. The average annualized investment cost f or the five strategies with the highest yields was $76.43 per acre. The annualized investment cost for the five strategies with the highest utility was $57.54 per acre. The difference in average utility between the two groups was $19.37 per acre. The strategy with the highest yield had a utility level of $295.77 per acre. The strategy with the highest utility had a utility level of $337.12 per acre. The analysis included only those costs associated with irrigation. Utility was more sensitive to labor costs and water charges than to the cost of energy and interest rates. The level of risk aversion made very little difference in the relative level of utility for the different strategies. If the moisture holding capacity of the soil was reduced then the level of risk aversion made a bigger difference in the relative level of utility. Close

• 57. [Article] Irrigation runoff control strategies

  Publised January 1986. Reprinted October 1997. Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension ...

  Citation × Citation Citation Abstract Copy Title: Irrigation runoff control strategies Author: Washington State University. Cooperative Extension, Pacific Northwest Cooperative Extension, United States. Dept. of Agriculture, Oregon State University. Extension Service, Trimmer, Walter L., University of Idaho. Cooperative Extension Service, Hansen, Hugh J. Publised January 1986. Reprinted October 1997. Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Irrigation runoff control strategies Author: Washington State University. Cooperative Extension, Pacific Northwest Cooperative Extension, United States. Dept. of Agriculture, Oregon State University. Extension Service, Trimmer, Walter L., University of Idaho. Cooperative Extension Service, Hansen, Hugh J. Publised January 1986. Reprinted October 1997. Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 58. [Article] Drip irrigation guide for potatoes

  Published October 2006. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Drip irrigation guide for potatoes Author: Pereira, Andre, Wang, Feng-Xin, Eldredge, Eric P., Flock, Rebecca, Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published October 2006. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Drip irrigation guide for potatoes Author: Pereira, Andre, Wang, Feng-Xin, Eldredge, Eric P., Flock, Rebecca, Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published October 2006. Revised January 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 59. [Article] Drip irrigation guide for growers of hybrid poplar

  Published December 2005. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http:/...

  Citation × Citation Citation Abstract Copy Title: Drip irrigation guide for growers of hybrid poplar Author: Flock, R., Pereria, A., Feibert, E., Oregon State University. Extension Service, Shock, C. C. (Clinton C.), O'Neill, M. Published December 2005. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Drip irrigation guide for growers of hybrid poplar Author: Flock, R., Pereria, A., Feibert, E., Oregon State University. Extension Service, Shock, C. C. (Clinton C.), O'Neill, M. Published December 2005. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 60. [Article] Drip irrigation guide for onion growers in the Treasure Valley

  Published December 2005. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http:/...

  Citation × Citation Citation Abstract Copy Title: Drip irrigation guide for onion growers in the Treasure Valley Author: Flock, R., Shock, C. A., Feibert, E., Jensen, L., Klauzer, J., Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published December 2005. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Drip irrigation guide for onion growers in the Treasure Valley Author: Flock, R., Shock, C. A., Feibert, E., Jensen, L., Klauzer, J., Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published December 2005. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 61. [Article] Application of Landsat to Evaluate Effects of Irrigation Forbearance

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Multidisciplinary Digital Publishing Institute. The published article can be found at: http://w...

  Citation × Citation Citation Abstract Copy Title: Application of Landsat to Evaluate Effects of Irrigation Forbearance Author: Hagimoto, Yutaka, Ciotti, Shannon P., Cuenca, Richard H. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Multidisciplinary Digital Publishing Institute. The published article can be found at: http://www.mdpi.com/journal/remotesensing. Title: Application of Landsat to Evaluate Effects of Irrigation Forbearance Author: Hagimoto, Yutaka, Ciotti, Shannon P., Cuenca, Richard H. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Multidisciplinary Digital Publishing Institute. The published article can be found at: http://www.mdpi.com/journal/remotesensing. Close

• 62. [Article] Developing an Agricultural Water Efficiency Strategy to Help Meet Oregon’s Water Needs

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Developing an Agricultural Water Efficiency Strategy to Help Meet Oregon’s Water Needs Author: Huntsinger, Teresa Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Developing an Agricultural Water Efficiency Strategy to Help Meet Oregon’s Water Needs Author: Huntsinger, Teresa Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 63. [Article] Requirements for successful irrigation systems in the Senegal River Basin (Mauritania)

  Implementation of a small-scale irrigation project in southern Mauritania is analyzed in this report. The main objective is to demonstrate that small-scale irrigation farming is the best suited solution ...

  Citation × Citation Citation Abstract Copy Title: Requirements for successful irrigation systems in the Senegal River Basin (Mauritania) Author: Abba, Fatima Zahra Implementation of a small-scale irrigation project in southern Mauritania is analyzed in this report. The main objective is to demonstrate that small-scale irrigation farming is the best suited solution for Mauritania's agriculture. To reach this objective different steps are taken in this study. The first step highlights the different aspects affecting the development of agriculture in the Senegal River basin such as climatic, environmental, and socio-economic constraints. The next step is the design of a small-scale irrigation system for a small region in the middle valley of the Senegal River called the Dirol plain. Finally, analysis and discussion of the design is made. This discussion centers on the problems faced during the design and the different assumptions made to implement it. The conclusion section addresses the feasibility of the design and gives recommendations that will help improve the design process for future work in the Senegal River basin. Title: Requirements for successful irrigation systems in the Senegal River Basin (Mauritania) Author: Abba, Fatima Zahra Implementation of a small-scale irrigation project in southern Mauritania is analyzed in this report. The main objective is to demonstrate that small-scale irrigation farming is the best suited solution for Mauritania's agriculture. To reach this objective different steps are taken in this study. The first step highlights the different aspects affecting the development of agriculture in the Senegal River basin such as climatic, environmental, and socio-economic constraints. The next step is the design of a small-scale irrigation system for a small region in the middle valley of the Senegal River called the Dirol plain. Finally, analysis and discussion of the design is made. This discussion centers on the problems faced during the design and the different assumptions made to implement it. The conclusion section addresses the feasibility of the design and gives recommendations that will help improve the design process for future work in the Senegal River basin. Close

• 64. [Article] The demand for electricity in western U.S. irrigated agriculture : a dual cost function analysis

  The overall objective of the research reported here is to empirically measure the ability of farmers to mitigate the impact of rising electricity prices by substituting relatively inexpensive alternative ...

  Citation × Citation Citation Abstract Copy Title: The demand for electricity in western U.S. irrigated agriculture : a dual cost function analysis Author: Connor, Jeffery Dean The overall objective of the research reported here is to empirically measure the ability of farmers to mitigate the impact of rising electricity prices by substituting relatively inexpensive alternative inputs. A dual cost methodology is employed because it allows theoretically consistent derivation of own price and factor substitution elasticities, conditional upon exogenously determined environmental, economic and technological constraints. Furthermore, the framework allows for an assessment of the appropriateness of producer cost minimization behavior, which has been assumed but not explicitly tested in earlier studies. A secondary objective is to analyze possible implications of future irrigation electricity price changes on producer, regional economic and electric utility company welfare. The most notable finding is that the demand for irrigation electricity is quite price elastic. This indicates that, historically, when the price of electricity has been relatively high, producers have found ways to use less of this input. The derived price elasticity of demand for irrigation electricity (-1.45) confirms results of other researchers. Gardener and Young; Whittlesey; and Maddigan, Chern and Rizy all estimated price elasticity for irrigation in the range from -1 to -2. Tests of the conditions necessary to maintain the assumption of cost minimization, do not confirm that this assumption is strictly justified in the present study. Title: The demand for electricity in western U.S. irrigated agriculture : a dual cost function analysis Author: Connor, Jeffery Dean The overall objective of the research reported here is to empirically measure the ability of farmers to mitigate the impact of rising electricity prices by substituting relatively inexpensive alternative inputs. A dual cost methodology is employed because it allows theoretically consistent derivation of own price and factor substitution elasticities, conditional upon exogenously determined environmental, economic and technological constraints. Furthermore, the framework allows for an assessment of the appropriateness of producer cost minimization behavior, which has been assumed but not explicitly tested in earlier studies. A secondary objective is to analyze possible implications of future irrigation electricity price changes on producer, regional economic and electric utility company welfare. The most notable finding is that the demand for irrigation electricity is quite price elastic. This indicates that, historically, when the price of electricity has been relatively high, producers have found ways to use less of this input. The derived price elasticity of demand for irrigation electricity (-1.45) confirms results of other researchers. Gardener and Young; Whittlesey; and Maddigan, Chern and Rizy all estimated price elasticity for irrigation in the range from -1 to -2. Tests of the conditions necessary to maintain the assumption of cost minimization, do not confirm that this assumption is strictly justified in the present study. Close

• 65. [Article] The Columbia basin irrigation project. A report by Columbia basin survey commission, state of Washington, 1920

  Gerald W. Williams Collection

  Citation × Citation Citation Abstract Copy Title: The Columbia basin irrigation project. A report by Columbia basin survey commission, state of Washington, 1920 Author: Chase, Marvin, Washington (State). Columbia Basin Survey Commission Gerald W. Williams Collection Title: The Columbia basin irrigation project. A report by Columbia basin survey commission, state of Washington, 1920 Author: Chase, Marvin, Washington (State). Columbia Basin Survey Commission Gerald W. Williams Collection Close

• 66. [Article] Crop evapotranspiration of winter wheat under deficit irrigation

  Citation × Citation Citation Abstract Copy Title: Crop evapotranspiration of winter wheat under deficit irrigation Author: Nuss, Gary Steven Title: Crop evapotranspiration of winter wheat under deficit irrigation Author: Nuss, Gary Steven Close

• 67. [Article] The impact of supplemental irrigation on farm organizations in Polk County Oregon

  Citation × Citation Citation Abstract Copy Title: The impact of supplemental irrigation on farm organizations in Polk County Oregon Author: Caldwell, Harvey Wilbur Title: The impact of supplemental irrigation on farm organizations in Polk County Oregon Author: Caldwell, Harvey Wilbur Close

• 68. [Article] The response of winter wheat to irrigation in the Willamette Valley

  Some consideration has been given to the irrigation of winter wheat in the Willamette Valley of Oregon. This important crop has yielded quite well since the development and introduction of the stiff-strawed, ...

  Citation × Citation Citation Abstract Copy Title: The response of winter wheat to irrigation in the Willamette Valley Author: Rossner, John Theodore Some consideration has been given to the irrigation of winter wheat in the Willamette Valley of Oregon. This important crop has yielded quite well since the development and introduction of the stiff-strawed, semi-dwarf wheats, but, because of the usually dry early summers, it has been suggested that irrigation of winter wheat could probably increase the yield still further. The objective of this study was to determine the response of winter wheat to supplemental irrigation when grown under various levels of spring applied nitrogen on two important soil series. Moisture changes in the soil were followed in late spring and early summer as another phase of the study. Two winter wheat varieties were sown in October 1966 at two locations in the Willamette Valley. Each variety received supplemental nitrogen in the early spring and irrigation in late May or in June. Grain was harvested about August 1 and the yield in bushels per acre was determined. Soil moisture changes were studied at the same two locations with the use of gypsum blocks buried in the soil at different depths and at another location by soil core samples. Readings from the gypsum blocks were converted to percent moisture in the soil by a series of calculations. Based on the increase of grain yields under the various treatments, the use of nitrogen fertilizer appears to be a more practical means of increasing grain yields than does irrigation. Only a slight response to irrigation was noted. Decrease in moisture content of the soil occurred particularly in the top four feet. The largest moisture decrease occurred in the top foot, the next largest decrease was in the second foot, then the third foot, and then the fourth foot. Some moisture decrease was noted below four feet; however, the amount of decrease was small. It appears from the limited observations that soils in the Willamette Valley contain enough moisture for wheat to complete its development with little or no moisture stress. Title: The response of winter wheat to irrigation in the Willamette Valley Author: Rossner, John Theodore Some consideration has been given to the irrigation of winter wheat in the Willamette Valley of Oregon. This important crop has yielded quite well since the development and introduction of the stiff-strawed, semi-dwarf wheats, but, because of the usually dry early summers, it has been suggested that irrigation of winter wheat could probably increase the yield still further. The objective of this study was to determine the response of winter wheat to supplemental irrigation when grown under various levels of spring applied nitrogen on two important soil series. Moisture changes in the soil were followed in late spring and early summer as another phase of the study. Two winter wheat varieties were sown in October 1966 at two locations in the Willamette Valley. Each variety received supplemental nitrogen in the early spring and irrigation in late May or in June. Grain was harvested about August 1 and the yield in bushels per acre was determined. Soil moisture changes were studied at the same two locations with the use of gypsum blocks buried in the soil at different depths and at another location by soil core samples. Readings from the gypsum blocks were converted to percent moisture in the soil by a series of calculations. Based on the increase of grain yields under the various treatments, the use of nitrogen fertilizer appears to be a more practical means of increasing grain yields than does irrigation. Only a slight response to irrigation was noted. Decrease in moisture content of the soil occurred particularly in the top four feet. The largest moisture decrease occurred in the top foot, the next largest decrease was in the second foot, then the third foot, and then the fourth foot. Some moisture decrease was noted below four feet; however, the amount of decrease was small. It appears from the limited observations that soils in the Willamette Valley contain enough moisture for wheat to complete its development with little or no moisture stress. Close

• 69. [Article] Irrigation requirements for selected Oregon locations

  Citation × Citation Citation Abstract Copy Title: Irrigation requirements for selected Oregon locations Author: Basketfield, Daniel L. Title: Irrigation requirements for selected Oregon locations Author: Basketfield, Daniel L. Close

• 70. [Article] Capital used in the development of newly irrigated farms on the north unit, Deschutes Project, Oregon

  Citation × Citation Citation Abstract Copy Title: Capital used in the development of newly irrigated farms on the north unit, Deschutes Project, Oregon Author: Van Winkle, Alfred Eugene Title: Capital used in the development of newly irrigated farms on the north unit, Deschutes Project, Oregon Author: Van Winkle, Alfred Eugene Close

• 71. [Article] Accuracy, range, and convenience of certain methods and devices used in measurement of irrigation water

  Citation × Citation Citation Abstract Copy Title: Accuracy, range, and convenience of certain methods and devices used in measurement of irrigation water Author: Neu, Harold Wesley Title: Accuracy, range, and convenience of certain methods and devices used in measurement of irrigation water Author: Neu, Harold Wesley Close

• 72. [Article] The effect of fertilizers on the yield and quality of fiber flax produced under irrigation

  Citation × Citation Citation Abstract Copy Title: The effect of fertilizers on the yield and quality of fiber flax produced under irrigation Author: Puri, Yesh Pal Title: The effect of fertilizers on the yield and quality of fiber flax produced under irrigation Author: Puri, Yesh Pal Close

• 73. [Article] Irrigation water quality

  Published February 1990. Reprinted January 1998. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extens...

  Citation × Citation Citation Abstract Copy Title: Irrigation water quality Author: Vomocil, James A., Oregon State University. Extension Service, Hart, John M. (John Mervyn), 1947- Published February 1990. Reprinted January 1998. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Irrigation water quality Author: Vomocil, James A., Oregon State University. Extension Service, Hart, John M. (John Mervyn), 1947- Published February 1990. Reprinted January 1998. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 74. [Article] Selected effects of additional irrigation in the Columbia Basin : a multiregional interindustry analysis

  Increasing demands for water related services of the Columbia River and its tributaries create conflicts between users During the 1970's the conflict has centered around three major water uses - irrigation, ...

  Citation × Citation Citation Abstract Copy Title: Selected effects of additional irrigation in the Columbia Basin : a multiregional interindustry analysis Author: Wilkins, John Russell Increasing demands for water related services of the Columbia River and its tributaries create conflicts between users During the 1970's the conflict has centered around three major water uses - irrigation, hydroelectric power generation, and fisheries. This study analyzes some of the tradeoffs between upstream depletion of water for irrigation and downstream use of the water for production of aluminum, which depends on large blocks of inexpensive hydroelectric energy The economic value of two projected increments of irrigated crops in 1985 and the consequent losses of economic value from less aluminum output due to reduced hydroelectric generation are analyzed in a 1985 multiregional inputoutput model of Washington, Oregon, and Idaho The analysis also estimates direct and indirect changes in output and employment by industry, State, and for the region. Results indicate that the 1985 incremental value of crop output from additional irrigation overshadows output losses in the regional aluminum industry For each additional dollar of crop production and processing, 4-7 cents are lost n regional aluminum and related output. Neither the crop production increases nor the aluminum production losses are large compared to the projected 1985 regional economy. However, the production changes are significant within each industry and probably would have considerable impact in localities with new irrigated lands or where aluminum production is significant. Indirect or support output in trade, services, transportation machinery, food processing, manufacture, and electric utilities are most affected by future irrigated crop output increases and aluminum output decreases Despite the largest aluminum output reductions, most of the effects occur in Washington, followed by Idaho and then Oregon. Title: Selected effects of additional irrigation in the Columbia Basin : a multiregional interindustry analysis Author: Wilkins, John Russell Increasing demands for water related services of the Columbia River and its tributaries create conflicts between users During the 1970's the conflict has centered around three major water uses - irrigation, hydroelectric power generation, and fisheries. This study analyzes some of the tradeoffs between upstream depletion of water for irrigation and downstream use of the water for production of aluminum, which depends on large blocks of inexpensive hydroelectric energy The economic value of two projected increments of irrigated crops in 1985 and the consequent losses of economic value from less aluminum output due to reduced hydroelectric generation are analyzed in a 1985 multiregional inputoutput model of Washington, Oregon, and Idaho The analysis also estimates direct and indirect changes in output and employment by industry, State, and for the region. Results indicate that the 1985 incremental value of crop output from additional irrigation overshadows output losses in the regional aluminum industry For each additional dollar of crop production and processing, 4-7 cents are lost n regional aluminum and related output. Neither the crop production increases nor the aluminum production losses are large compared to the projected 1985 regional economy. However, the production changes are significant within each industry and probably would have considerable impact in localities with new irrigated lands or where aluminum production is significant. Indirect or support output in trade, services, transportation machinery, food processing, manufacture, and electric utilities are most affected by future irrigated crop output increases and aluminum output decreases Despite the largest aluminum output reductions, most of the effects occur in Washington, followed by Idaho and then Oregon. Close

• 75. [Article] Determination of irrigation frequencies and amounts by soil moisture sampling and gypsum electrical resistance blocks

  Citation × Citation Citation Abstract Copy Title: Determination of irrigation frequencies and amounts by soil moisture sampling and gypsum electrical resistance blocks Author: Abd El-Samie, Ahmed Gamal Title: Determination of irrigation frequencies and amounts by soil moisture sampling and gypsum electrical resistance blocks Author: Abd El-Samie, Ahmed Gamal Close

• 76. [Article] Efficiency performance criteria for irrigation systems

  Citation × Citation Citation Abstract Copy Title: Efficiency performance criteria for irrigation systems Author: Shearer, Marvin N., Hansen, Hugh J. Title: Efficiency performance criteria for irrigation systems Author: Shearer, Marvin N., Hansen, Hugh J. Close

• 77. [Article] The irrigation of bearing orchards in Jackson County, Oregon

  Citation × Citation Citation Abstract Copy Title: The irrigation of bearing orchards in Jackson County, Oregon Author: Allen, Ralph Wilmer Title: The irrigation of bearing orchards in Jackson County, Oregon Author: Allen, Ralph Wilmer Close

• 78. [Article] Evaporation as an aid in calculating irrigation requirements for crops

  Citation × Citation Citation Abstract Copy Title: Evaporation as an aid in calculating irrigation requirements for crops Author: Lugo-Blanco, Julio Jose Title: Evaporation as an aid in calculating irrigation requirements for crops Author: Lugo-Blanco, Julio Jose Close

• 79. [Article] An economic analysis of resource substitution with sprinkler irrigation systems in use in Oregon's Northern Columbia River Basin counties

  Citation × Citation Citation Abstract Copy Title: An economic analysis of resource substitution with sprinkler irrigation systems in use in Oregon's Northern Columbia River Basin counties Author: Erhabor, Patrick Osaretin Title: An economic analysis of resource substitution with sprinkler irrigation systems in use in Oregon's Northern Columbia River Basin counties Author: Erhabor, Patrick Osaretin Close

• 80. [Article] A study of the factors involved in the economic use of water and water cost of dry matter on several irrigated areas in Oregon

  Citation × Citation Citation Abstract Copy Title: A study of the factors involved in the economic use of water and water cost of dry matter on several irrigated areas in Oregon Author: Hardman, George, 1890- Title: A study of the factors involved in the economic use of water and water cost of dry matter on several irrigated areas in Oregon Author: Hardman, George, 1890- Close

• 81. [Article] Drip irrigation: an introduction

  Published October 2006. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://...

  Citation × Citation Citation Abstract Copy Title: Drip irrigation: an introduction Author: Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published October 2006. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Drip irrigation: an introduction Author: Oregon State University. Extension Service, Shock, C. C. (Clinton C.) Published October 2006. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 82. [Article] Estimated crop production costs on loam soils with side-roll irrigation systems, Oregon's Columbia Basin, 1978

  Published November 1978. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/cata...

  Citation × Citation Citation Abstract Copy Title: Estimated crop production costs on loam soils with side-roll irrigation systems, Oregon's Columbia Basin, 1978 Author: Holst, David, Oregon State University. Extension Service Published November 1978. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Estimated crop production costs on loam soils with side-roll irrigation systems, Oregon's Columbia Basin, 1978 Author: Holst, David, Oregon State University. Extension Service Published November 1978. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 83. [Article] Estimated crop production costs on sandy soils with center-pivot irrigation systems, Oregon's Columbia Basin, 1978

  Published November 1978. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/cata...

  Citation × Citation Citation Abstract Copy Title: Estimated crop production costs on sandy soils with center-pivot irrigation systems, Oregon's Columbia Basin, 1978 Author: Holst, David, Oregon State University. Extension Service Published November 1978. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Estimated crop production costs on sandy soils with center-pivot irrigation systems, Oregon's Columbia Basin, 1978 Author: Holst, David, Oregon State University. Extension Service Published November 1978. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 84. [Article] Irrigation in Klamath County : cooperative irrigation investigation with the Office of Experiment Stations, United States Department of Agriculture

  Published April 1905. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog...

  Citation × Citation Citation Abstract Copy Title: Irrigation in Klamath County : cooperative irrigation investigation with the Office of Experiment Stations, United States Department of Agriculture Author: Oregon Agricultural Experiment Station, Kent, F. L. (Fred LeRoy), 1868- Published April 1905. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Irrigation in Klamath County : cooperative irrigation investigation with the Office of Experiment Stations, United States Department of Agriculture Author: Oregon Agricultural Experiment Station, Kent, F. L. (Fred LeRoy), 1868- Published April 1905. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 85. [Article] Irrigation management practices checklist for Oregon

  Published August 1996. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo...

  Citation × Citation Citation Abstract Copy Title: Irrigation management practices checklist for Oregon Author: English, Marshall J., Oregon State University. Extension Service, Mittelstadt, Robert, Miner, J. Ronald Published August 1996. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Irrigation management practices checklist for Oregon Author: English, Marshall J., Oregon State University. Extension Service, Mittelstadt, Robert, Miner, J. Ronald Published August 1996. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 86. [Article] Growing irrigated soybeans in the Pacific Northwest

  Published January 2010. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Growing irrigated soybeans in the Pacific Northwest Author: Feibert, Erik Bruno Goncalves, Oregon State University. Extension Service, Norberg, O. Steven, Shock, C. C. (Clinton C.) Published January 2010. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Growing irrigated soybeans in the Pacific Northwest Author: Feibert, Erik Bruno Goncalves, Oregon State University. Extension Service, Norberg, O. Steven, Shock, C. C. (Clinton C.) Published January 2010. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 87. [Article] Irrigated farms under development (northern Jefferson County, Oregon)

  Published January 1952. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Irrigated farms under development (northern Jefferson County, Oregon) Author: Plath, C. V., Oregon State College. Agricultural Experiment Station, Osborn, Howard A., 1925- Published January 1952. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Irrigated farms under development (northern Jefferson County, Oregon) Author: Plath, C. V., Oregon State College. Agricultural Experiment Station, Osborn, Howard A., 1925- Published January 1952. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 88. [Article] Water management effects on birdsfoot trefoil seed production

  There is no information available on water management of birdsfoot trefoil grown for seed. Information is also not available describing how to minimize seed losses due to shattering in order to obtain ...

  Citation × Citation Citation Abstract Copy Title: Water management effects on birdsfoot trefoil seed production Author: García-Díaz, Carlos Alberto There is no information available on water management of birdsfoot trefoil grown for seed. Information is also not available describing how to minimize seed losses due to shattering in order to obtain consistently high birdsfoot trefoil seed yields. The objectives of this research are to: (i) quantify crop water use, effects of soil-water availability and optimal water management conditions for birdsfoot trefoil grown for seed, (ii) determine the effects of irrigation timing and amount on flower production, seed yield, and yield components, and (iii) quantify the effects of soil-water availability on seed shattering and determine optimal harvest time to reduce seed yield losses due to shattering. Five supplemental irrigations treatments and a non-irrigated control were applied in 1994 and 1995; in 1996, only treatments low stress and non irrigated control were investigated, near Corvallis, OR on a Woodburn silt loam soil (fine-silty, mixed, mesic Aquultic Argixeroll). Increasing amounts of applied water increased seasonal ET[subscript c] with low stressed plants having the greatest ET[subscript c] and non-irrigated control plants the least. The fraction of available soil-water used was primarily dependent upon the irrigation depletion percentage and secondarily dependent upon irrigation replacement amount. Soil-water conditions favorable for vegetative development and seed yield water use efficiency are opposite. Birdsfoot trefoil grown for seed requires minimal or no supplemental irrigation. For non-irrigated conditions, the crop water requirement ranges from 240 to 255 mm. In the first year of production, plants under low-stress conditions sustained flowering longer than with limited or no irrigation applications. Flowering was not affected by irrigation in subsequent years of production. Total above-ground phytomass production was correlated with the amount of applied irrigation water (r=0.92). Umbel density and number of seeds per pod are the primary determinants of total seed yield (r=0.77 and 0.92, respectively). Manipulation of the reproductive development pattern by different water application times and amounts does not affect peak seed shattering events. Crop-water stress status affects the percentage of total shattered seeds shattered at harvest time (r=-0.76). Increasing amounts of applied water increase the percentage of potential shatter losses that will shatter by harvest time (r=0.65). Seed shatter losses fluctuate during the reproductive development period but are not influenced by the water application treatments. Climatic variables as measured in this experiment cannot be used to predict the time of peak seed shatter events. A total of 109 heat units are needed from the time from initial pod dehiscence until rapid shattering occurs. Title: Water management effects on birdsfoot trefoil seed production Author: García-Díaz, Carlos Alberto There is no information available on water management of birdsfoot trefoil grown for seed. Information is also not available describing how to minimize seed losses due to shattering in order to obtain consistently high birdsfoot trefoil seed yields. The objectives of this research are to: (i) quantify crop water use, effects of soil-water availability and optimal water management conditions for birdsfoot trefoil grown for seed, (ii) determine the effects of irrigation timing and amount on flower production, seed yield, and yield components, and (iii) quantify the effects of soil-water availability on seed shattering and determine optimal harvest time to reduce seed yield losses due to shattering. Five supplemental irrigations treatments and a non-irrigated control were applied in 1994 and 1995; in 1996, only treatments low stress and non irrigated control were investigated, near Corvallis, OR on a Woodburn silt loam soil (fine-silty, mixed, mesic Aquultic Argixeroll). Increasing amounts of applied water increased seasonal ET[subscript c] with low stressed plants having the greatest ET[subscript c] and non-irrigated control plants the least. The fraction of available soil-water used was primarily dependent upon the irrigation depletion percentage and secondarily dependent upon irrigation replacement amount. Soil-water conditions favorable for vegetative development and seed yield water use efficiency are opposite. Birdsfoot trefoil grown for seed requires minimal or no supplemental irrigation. For non-irrigated conditions, the crop water requirement ranges from 240 to 255 mm. In the first year of production, plants under low-stress conditions sustained flowering longer than with limited or no irrigation applications. Flowering was not affected by irrigation in subsequent years of production. Total above-ground phytomass production was correlated with the amount of applied irrigation water (r=0.92). Umbel density and number of seeds per pod are the primary determinants of total seed yield (r=0.77 and 0.92, respectively). Manipulation of the reproductive development pattern by different water application times and amounts does not affect peak seed shattering events. Crop-water stress status affects the percentage of total shattered seeds shattered at harvest time (r=-0.76). Increasing amounts of applied water increase the percentage of potential shatter losses that will shatter by harvest time (r=0.65). Seed shatter losses fluctuate during the reproductive development period but are not influenced by the water application treatments. Climatic variables as measured in this experiment cannot be used to predict the time of peak seed shatter events. A total of 109 heat units are needed from the time from initial pod dehiscence until rapid shattering occurs. Close

• 89. [Article] Development of an expert system for irrigation and fertilization management in the Pacific Northwest

  Recent advances in computer technology have made possible the development of expert systems. Expert systems are computer programs that perform at the level of a human expert. Expert systems can help integrate ...

  Citation × Citation Citation Abstract Copy Title: Development of an expert system for irrigation and fertilization management in the Pacific Northwest Author: Cao, Weidong Recent advances in computer technology have made possible the development of expert systems. Expert systems are computer programs that perform at the level of a human expert. Expert systems can help integrate and apply diverse sources of information and expertise to problems of integrated crop management. A prototype Crop Management eXpert (CMX) system has been developed. The primary goal of CMX is to provide recommendations on optimal irrigation and fertilization scheduling for wheat production in the Pacific Northwest. This system can be used by farmers and/or extension agents. OUS II Shell has been used as a implementation tool. To build this rule - based expert system, a development strategy, commonly used in the construction of expert systems, consisting of 1 ) identification; 2) conceptualization; 3) formalization; 4) implementation; and 5) testing was applied. CMX is composed of modules for irrigation and fertilization management. For irrigation management, CMX is mainly involved in the irrigation scheduling which is the major part of irrigation management. Irrigation strategies have been applied in irrigation decision making. For each strategy, timing criteria which generally consist of management allowed depletion, soil water potential, leaf water potential, and water stress indices have been used. The system provides farmers with irrigation scenarios which determine when and how much water to apply. CMX represents an integration of conventional computing and expert systems technology designed to provide expert recommendations enabling farmers to obtain the best return on their water and fertilizer investment. For fertilization management, a variety of variables have been taken into considered. Crop growth stages, soil moisture, nutrient analysis, protein requirement, and application methods are important factors for the fertilizer decision making. Several constraints have been used in optimal fertilizer advice. CMX can focus only on relevant information, thus reducing the problem space to a manageable size and significantly, improving the efficiency of the system. The facility of the expert system to explain the decision-making process enables users to better understand the underlying assumptions, facts, and reasoning used to generate recommendations. The CMX prototype demonstrates the feasibility of employing expert systems technology in agricultural applications. CMX has been validated and evaluated. The survey results showed that this prototype was successful in capturing domain experts' knowledge as rules and providing advice on the irrigation and fertilization management for wheat. Title: Development of an expert system for irrigation and fertilization management in the Pacific Northwest Author: Cao, Weidong Recent advances in computer technology have made possible the development of expert systems. Expert systems are computer programs that perform at the level of a human expert. Expert systems can help integrate and apply diverse sources of information and expertise to problems of integrated crop management. A prototype Crop Management eXpert (CMX) system has been developed. The primary goal of CMX is to provide recommendations on optimal irrigation and fertilization scheduling for wheat production in the Pacific Northwest. This system can be used by farmers and/or extension agents. OUS II Shell has been used as a implementation tool. To build this rule - based expert system, a development strategy, commonly used in the construction of expert systems, consisting of 1 ) identification; 2) conceptualization; 3) formalization; 4) implementation; and 5) testing was applied. CMX is composed of modules for irrigation and fertilization management. For irrigation management, CMX is mainly involved in the irrigation scheduling which is the major part of irrigation management. Irrigation strategies have been applied in irrigation decision making. For each strategy, timing criteria which generally consist of management allowed depletion, soil water potential, leaf water potential, and water stress indices have been used. The system provides farmers with irrigation scenarios which determine when and how much water to apply. CMX represents an integration of conventional computing and expert systems technology designed to provide expert recommendations enabling farmers to obtain the best return on their water and fertilizer investment. For fertilization management, a variety of variables have been taken into considered. Crop growth stages, soil moisture, nutrient analysis, protein requirement, and application methods are important factors for the fertilizer decision making. Several constraints have been used in optimal fertilizer advice. CMX can focus only on relevant information, thus reducing the problem space to a manageable size and significantly, improving the efficiency of the system. The facility of the expert system to explain the decision-making process enables users to better understand the underlying assumptions, facts, and reasoning used to generate recommendations. The CMX prototype demonstrates the feasibility of employing expert systems technology in agricultural applications. CMX has been validated and evaluated. The survey results showed that this prototype was successful in capturing domain experts' knowledge as rules and providing advice on the irrigation and fertilization management for wheat. Close

• 90. [Article] Electrical resistance gypsum blocks for sceduling irrigations

  Publised March 1963. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog...

  Citation × Citation Citation Abstract Copy Title: Electrical resistance gypsum blocks for sceduling irrigations Author: Shearer, Marvin N., Oregon State University. Cooperative Extension Service Publised March 1963. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Electrical resistance gypsum blocks for sceduling irrigations Author: Shearer, Marvin N., Oregon State University. Cooperative Extension Service Publised March 1963. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 91. [Article] Soil Water Tension Irrigation Criteria Affects Both Stevia Rebaudiana Leaf Yield and Leaf Steviol Glycoside Composition

  Stevia (Stevia rebaudiana) is a perennial herbaceous plant native to Paraguay and used traditionally by the native Guarani peoples for centuries to sweeten medicinal teas. Stevia has only been commercially ...

  Citation × Citation Citation Abstract Copy Title: Soil Water Tension Irrigation Criteria Affects Both Stevia Rebaudiana Leaf Yield and Leaf Steviol Glycoside Composition Author: Parris, Cheryl A. Stevia (Stevia rebaudiana) is a perennial herbaceous plant native to Paraguay and used traditionally by the native Guarani peoples for centuries to sweeten medicinal teas. Stevia has only been commercially cultivated over the past 50 years and cultural practice information suitable for implementation by growers is limited. Currently stevia’s commercial value is found in its steviol glycoside content, especially rebaudioside A. Growers seek information to maximize productivity of rebaudioside A through improved cultural practices. Irrigation management is one of several important agronomic techniques growers can use to obtain maximum yield while also pursuing water use efficiency. The current trial investigated the effect that soil water tension as an irrigation onset criteria had on stevia dry leaf yields, steviol glycoside content and yield, and steviol glycoside ratios. The experiment was conducted in a field of Owyhee silt loam (coarse-silty, mixed, mesic Xerollic Camborthid) at the Oregon State University, Malheur Experiment Station, Ontario, Oregon, N 43° 58' 53.273'' W 117° 1' 26.396''. Two stevia varieties, SW109 and SW129 (S&W Seed Company Inc., Fresno, California), were subjected to soil water tension irrigation criteria of 10, 20, 40, 60, 80, kPa over a 57-day trial period. Harvested plant material was measured for dry leaf yield and several steviol glycosides. Analysis of variance showed significant variety differences in leaf yield, leaf stevioside and rebaudioside A content and yield, and steviol glycoside ratios (P=0.05). Examining the data by analysis of variance, dry leaf yield, stevioside%, rebaudioside C %, total steviol glycoside (TSG), rebaudioside C yield, and TSG % yield had significant higher results among the wetter compared to the drier soil water tension criteria treatments, yet a preferred treatment regime was not was not clearly evident. When comparing varieties by regression analysis, results showed a highly significant decrease in stevioside % content, and an increase in the ratio of rebaudioside A to stevioside from drier to wetter irrigation onset criteria, whereas, rebaudioside A % content did not show any significant trend at differing irrigation criteria. The results indicate that maximizing dry leaf productivity directly affects the total rebaudioside A yield, which in turn can provide increased crop value to the grower. Irrigating near 10kPa produced higher dry leaf yield and total rebaudioside A yield, than irrigation at drier criteria. Irrigating stevia at 10 kPa at full canopy, the crop coefficient, k[subscript c], was equivalent to 0.97 ET₀, averaging 6.4 mm·d⁻¹ for the days measured. Title: Soil Water Tension Irrigation Criteria Affects Both Stevia Rebaudiana Leaf Yield and Leaf Steviol Glycoside Composition Author: Parris, Cheryl A. Stevia (Stevia rebaudiana) is a perennial herbaceous plant native to Paraguay and used traditionally by the native Guarani peoples for centuries to sweeten medicinal teas. Stevia has only been commercially cultivated over the past 50 years and cultural practice information suitable for implementation by growers is limited. Currently stevia’s commercial value is found in its steviol glycoside content, especially rebaudioside A. Growers seek information to maximize productivity of rebaudioside A through improved cultural practices. Irrigation management is one of several important agronomic techniques growers can use to obtain maximum yield while also pursuing water use efficiency. The current trial investigated the effect that soil water tension as an irrigation onset criteria had on stevia dry leaf yields, steviol glycoside content and yield, and steviol glycoside ratios. The experiment was conducted in a field of Owyhee silt loam (coarse-silty, mixed, mesic Xerollic Camborthid) at the Oregon State University, Malheur Experiment Station, Ontario, Oregon, N 43° 58' 53.273'' W 117° 1' 26.396''. Two stevia varieties, SW109 and SW129 (S&W Seed Company Inc., Fresno, California), were subjected to soil water tension irrigation criteria of 10, 20, 40, 60, 80, kPa over a 57-day trial period. Harvested plant material was measured for dry leaf yield and several steviol glycosides. Analysis of variance showed significant variety differences in leaf yield, leaf stevioside and rebaudioside A content and yield, and steviol glycoside ratios (P=0.05). Examining the data by analysis of variance, dry leaf yield, stevioside%, rebaudioside C %, total steviol glycoside (TSG), rebaudioside C yield, and TSG % yield had significant higher results among the wetter compared to the drier soil water tension criteria treatments, yet a preferred treatment regime was not was not clearly evident. When comparing varieties by regression analysis, results showed a highly significant decrease in stevioside % content, and an increase in the ratio of rebaudioside A to stevioside from drier to wetter irrigation onset criteria, whereas, rebaudioside A % content did not show any significant trend at differing irrigation criteria. The results indicate that maximizing dry leaf productivity directly affects the total rebaudioside A yield, which in turn can provide increased crop value to the grower. Irrigating near 10kPa produced higher dry leaf yield and total rebaudioside A yield, than irrigation at drier criteria. Irrigating stevia at 10 kPa at full canopy, the crop coefficient, k[subscript c], was equivalent to 0.97 ET₀, averaging 6.4 mm·d⁻¹ for the days measured. Close

• 92. [Article] Simulating farm irrigation system energy requirements

  The work upon which this publication is based was supported in part by funds provided by the United States Department of the Interior, Office of Water Research and Technology, as authorized under the Water ...

  Citation × Citation Citation Abstract Copy Title: Simulating farm irrigation system energy requirements Author: Wolfe, John W. (John William), 1917-, Wensink, Robert B., Kizer, Michael A. The work upon which this publication is based was supported in part by funds provided by the United States Department of the Interior, Office of Water Research and Technology, as authorized under the Water Resources Research Act of 1964, Public Law 88-379. Title: Simulating farm irrigation system energy requirements Author: Wolfe, John W. (John William), 1917-, Wensink, Robert B., Kizer, Michael A. The work upon which this publication is based was supported in part by funds provided by the United States Department of the Interior, Office of Water Research and Technology, as authorized under the Water Resources Research Act of 1964, Public Law 88-379. Close

• 93. [Article] Irrigation system walk-through inspection analysis

  Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.e...

  Citation × Citation Citation Abstract Copy Title: Irrigation system walk-through inspection analysis Author: Pacific Northwest Cooperative Extension Service, Washington State University. Cooperative Extension, University of Idaho. Cooperative Extension, Oregon State University. Extension Service, Trimmer, Walter L., Hansen, Hugh J. Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Irrigation system walk-through inspection analysis Author: Pacific Northwest Cooperative Extension Service, Washington State University. Cooperative Extension, University of Idaho. Cooperative Extension, Oregon State University. Extension Service, Trimmer, Walter L., Hansen, Hugh J. Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 94. [Article] Sizing irrigation mainlines and fittings

  Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.e...

  Citation × Citation Citation Abstract Copy Title: Sizing irrigation mainlines and fittings Author: Washington State University. Cooperative Extension, United States. Dept. of Agriculture, Oregon State University. Extension Service, Trimmer, Walter L., University of Idaho. Cooperative Extension Service, Hansen, Hugh J. Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Sizing irrigation mainlines and fittings Author: Washington State University. Cooperative Extension, United States. Dept. of Agriculture, Oregon State University. Extension Service, Trimmer, Walter L., University of Idaho. Cooperative Extension Service, Hansen, Hugh J. Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 95. [Article] Managing irrigation water quality for crop production in the Pacific Northwest

  Published August 2007. Reviewed December 2014. Please check for up-to-date informatin in the OSU Extension Service Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Managing irrigation water quality for crop production in the Pacific Northwest Author: Washington State University. Extension, Pacific Northwest Cooperative Extension, Horneck, Donald Arthur, Ellsworth, Jason W., Sullivan, Dan M. (Dan Matthew), 1954-, University of Idaho. Extension, Hopkins, Bryan G., Oregon State University. Extension Service, Stevens, Robert G. Published August 2007. Reviewed December 2014. Please check for up-to-date informatin in the OSU Extension Service Catalog: http://extension.oregonstate.edu/catalog Title: Managing irrigation water quality for crop production in the Pacific Northwest Author: Washington State University. Extension, Pacific Northwest Cooperative Extension, Horneck, Donald Arthur, Ellsworth, Jason W., Sullivan, Dan M. (Dan Matthew), 1954-, University of Idaho. Extension, Hopkins, Bryan G., Oregon State University. Extension Service, Stevens, Robert G. Published August 2007. Reviewed December 2014. Please check for up-to-date informatin in the OSU Extension Service Catalog: http://extension.oregonstate.edu/catalog Close

• 96. [Article] Irrigation scheduling

  Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.e...

  Citation × Citation Citation Abstract Copy Title: Irrigation scheduling Author: Washington State University. Cooperative Extension, United States. Dept. of Agriculture, Oregon State University. Extension Service, Trimmer, Walter L., University of Idaho. Cooperative Extension Service, Hansen, Hugh J. Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Irrigation scheduling Author: Washington State University. Cooperative Extension, United States. Dept. of Agriculture, Oregon State University. Extension Service, Trimmer, Walter L., University of Idaho. Cooperative Extension Service, Hansen, Hugh J. Declared out of print May 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 97. [Article] Management guide for drip irrigation on seed carrots in central Oregon

  Published November 2004. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Management guide for drip irrigation on seed carrots in central Oregon Author: Butler, M. D., Weber, C. E. (Caroline E.), Klauzer, J., Oregon State University. Extension Service, Holliday, B. A., Campbell, C. K. Published November 2004. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Management guide for drip irrigation on seed carrots in central Oregon Author: Butler, M. D., Weber, C. E. (Caroline E.), Klauzer, J., Oregon State University. Extension Service, Holliday, B. A., Campbell, C. K. Published November 2004. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 98. [Article] Strategies for reducing irrigation water use

  Published July 2001. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://ex...

  Citation × Citation Citation Abstract Copy Title: Strategies for reducing irrigation water use Author: Oregon State University. Extension Service, Shock, C. C. (Clinton C.), Jensen, Lynn Published July 2001. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Strategies for reducing irrigation water use Author: Oregon State University. Extension Service, Shock, C. C. (Clinton C.), Jensen, Lynn Published July 2001. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 99. [Article] Water and Soil Management Practices to Enhance Plant Growth, Berry Development, and Fruit Quality of Northern Highbush Blueberry (Vaccinium corymbosum L.)

  Drought and mandatory water restrictions are limiting the availability of irrigation water in many important blueberry growing regions and new strategies are needed to maintain yield and fruit quality ...

  Citation × Citation Citation Abstract Copy Title: Water and Soil Management Practices to Enhance Plant Growth, Berry Development, and Fruit Quality of Northern Highbush Blueberry (Vaccinium corymbosum L.) Author: Almutairi, Khalid F. Drought and mandatory water restrictions are limiting the availability of irrigation water in many important blueberry growing regions and new strategies are needed to maintain yield and fruit quality with less water. Three potential options for reducing water use, including deficit irrigation, irrigation cut-offs, and crop thinning, were evaluated for 2 years in a mature planting of northern highbush blueberry (Vaccinium corymbosum L. ‘Elliott’). Treatments consisted of no thinning and 50% crop removal in combination with either full irrigation at 100% of estimated crop evapotranspiration (ETsubscript c]), deficit irrigation at 50% ET[subscript c] (applied for the entire growing season), or full irrigation with irrigation cut-off for 4–6 weeks during early or late stages of fruit development. Stem water potential was similar with full and deficit irrigation but, regardless of crop thinning, declined by 0.5–0.6 MPa when irrigation was cut-off early and by > 2.0 MPa when irrigation was cut-off late. In one or both years, the fruiting season was advanced with either deficit irrigation or late cut-off, whereas cutting off irrigation early delayed the season. Yield was not affected by deficit irrigation in plants with a full crop load but was reduced by an average of 35% when irrigation was cut-off late each year. Cutting off irrigation early likewise reduced yield, but only in the second year when the plants were not thinned; however, early cut-off also reduced fruit soluble solids and berry weight by 7% to 24%compared to full irrigation. Cutting off irrigation late produced the smallest and firmest fruit with the highest soluble solids and total acidity among the treatments, as well as the slowest rate of fruit loss in cold storage. Deficit irrigation had the least effect on fruit quality and, based on these results, appears to be the most viable option for maintaining yield with less water (2.5 ML·ha⁻¹ less water per season). A second study was conducted in a 7-year-old field of certified organic highbush blueberry. Two cultivars (‘Duke’ and ‘Liberty’) mulched with either porous polyethylene ground cover (“weed mat”) or yard debris compost topped with sawdust (sawdust+compost) and each fertilized with either feather meal or fish emulsion were evaluated. One-year-old fruiting laterals were randomly-selected at three heights (top, middle, and bottom) on the east and west side of the plants. Bud, flower, and fruit development were monitored through fruit harvest. There was relatively little effect of mulch type or fertilizer source on the measured variables. Fruit harvest occurred ≈8 d after the fruit were fully blue and ranged from 2-25 July 2012 and 26 June-3 July 2013 in ‘Duke’ and from 1-20 Aug. 2012 and 17 July-7 Aug. 2013 in ‘Liberty’. Proportionally more fruit buds occurred on middle laterals than upper and lower laterals. The dates of bud swell and bud break were not affected by cultivar or lateral position. ‘Duke’ and ‘Liberty’ produced 6-8 and 7-9 flowers/bud, respectively. Fruit set was high in both cultivars, averaging ≈95%. However, 13-18% and 29-38 % of the initial set fruit dropped in ’Duke’ and ‘Liberty’ in late May to early June. Fruit ripening was more uniform within clusters in ‘Duke’ than in ‘Liberty’, and average fruit size was similar among harvests in ‘Duke’ but decreased by 25-40% between the first and last harvest in ‘Liberty’. Fruit matured 3−5 d earlier on the east side of the canopy than on the west side. The results suggest that pruning proportionally more on the lower part of the canopy than on the upper part will result in larger fruit at harvest than uniform pruning throughout the bush. The final study was conducted to determine the potential of applying micronized elemental sulfur (S°) by chemigation through the drip system to reduce high soil pH in a new planting of ‘Duke’ blueberry. The S° was mixed with water and injected weekly for 2 months prior to planting, as well as 2 years after planting, atrates of 0, 50, 100 and 150 kg·ha⁻¹ per year, and was compared to the conventional practice of incorporating prilled S° into the soil prior to planting (two applications of 750 kg·ha⁻¹ each). Chemigation quickly reduced soil pH (0-10 cm) within a month from 6.6 with no S° to 6.1 with 50 kg·ha-1 S° and 5.8 with 100 or 150 kg·ha⁻¹ S°. The change was short-term, however, and by May of the following year, soil pH averaged 6.7, 6.5, 6.2, and 6.1 with each increasing rate of S° chemigation, respectively. The conventional treatment, in comparison, averaged 6.6 on the first date and 6.3 on the second date. In July of the following year, soil pH ranged from an average of 6.4 with no S° to 6.2 with 150 kg·ha⁻¹ S° and 5.5 with prilled S°. Soil pH declined thereafter to as low as 5.9 with additional S° chemigation and at lower depths (10-30 cm) was similar to the conventional treatment. None of the treatments had any effect on winter pruning weight in year 1 or on yield, berry weight, and plant dry weight in year 2. Chemigation with S° can be used to quickly reduce soil pH following planting and, therefore, may be a useful practice to correct high pH problems in established blueberry fields. However, it was less effective and more time consuming than applying prilled S° prior to planting. Title: Water and Soil Management Practices to Enhance Plant Growth, Berry Development, and Fruit Quality of Northern Highbush Blueberry (Vaccinium corymbosum L.) Author: Almutairi, Khalid F. Drought and mandatory water restrictions are limiting the availability of irrigation water in many important blueberry growing regions and new strategies are needed to maintain yield and fruit quality with less water. Three potential options for reducing water use, including deficit irrigation, irrigation cut-offs, and crop thinning, were evaluated for 2 years in a mature planting of northern highbush blueberry (Vaccinium corymbosum L. ‘Elliott’). Treatments consisted of no thinning and 50% crop removal in combination with either full irrigation at 100% of estimated crop evapotranspiration (ETsubscript c]), deficit irrigation at 50% ET[subscript c] (applied for the entire growing season), or full irrigation with irrigation cut-off for 4–6 weeks during early or late stages of fruit development. Stem water potential was similar with full and deficit irrigation but, regardless of crop thinning, declined by 0.5–0.6 MPa when irrigation was cut-off early and by > 2.0 MPa when irrigation was cut-off late. In one or both years, the fruiting season was advanced with either deficit irrigation or late cut-off, whereas cutting off irrigation early delayed the season. Yield was not affected by deficit irrigation in plants with a full crop load but was reduced by an average of 35% when irrigation was cut-off late each year. Cutting off irrigation early likewise reduced yield, but only in the second year when the plants were not thinned; however, early cut-off also reduced fruit soluble solids and berry weight by 7% to 24%compared to full irrigation. Cutting off irrigation late produced the smallest and firmest fruit with the highest soluble solids and total acidity among the treatments, as well as the slowest rate of fruit loss in cold storage. Deficit irrigation had the least effect on fruit quality and, based on these results, appears to be the most viable option for maintaining yield with less water (2.5 ML·ha⁻¹ less water per season). A second study was conducted in a 7-year-old field of certified organic highbush blueberry. Two cultivars (‘Duke’ and ‘Liberty’) mulched with either porous polyethylene ground cover (“weed mat”) or yard debris compost topped with sawdust (sawdust+compost) and each fertilized with either feather meal or fish emulsion were evaluated. One-year-old fruiting laterals were randomly-selected at three heights (top, middle, and bottom) on the east and west side of the plants. Bud, flower, and fruit development were monitored through fruit harvest. There was relatively little effect of mulch type or fertilizer source on the measured variables. Fruit harvest occurred ≈8 d after the fruit were fully blue and ranged from 2-25 July 2012 and 26 June-3 July 2013 in ‘Duke’ and from 1-20 Aug. 2012 and 17 July-7 Aug. 2013 in ‘Liberty’. Proportionally more fruit buds occurred on middle laterals than upper and lower laterals. The dates of bud swell and bud break were not affected by cultivar or lateral position. ‘Duke’ and ‘Liberty’ produced 6-8 and 7-9 flowers/bud, respectively. Fruit set was high in both cultivars, averaging ≈95%. However, 13-18% and 29-38 % of the initial set fruit dropped in ’Duke’ and ‘Liberty’ in late May to early June. Fruit ripening was more uniform within clusters in ‘Duke’ than in ‘Liberty’, and average fruit size was similar among harvests in ‘Duke’ but decreased by 25-40% between the first and last harvest in ‘Liberty’. Fruit matured 3−5 d earlier on the east side of the canopy than on the west side. The results suggest that pruning proportionally more on the lower part of the canopy than on the upper part will result in larger fruit at harvest than uniform pruning throughout the bush. The final study was conducted to determine the potential of applying micronized elemental sulfur (S°) by chemigation through the drip system to reduce high soil pH in a new planting of ‘Duke’ blueberry. The S° was mixed with water and injected weekly for 2 months prior to planting, as well as 2 years after planting, atrates of 0, 50, 100 and 150 kg·ha⁻¹ per year, and was compared to the conventional practice of incorporating prilled S° into the soil prior to planting (two applications of 750 kg·ha⁻¹ each). Chemigation quickly reduced soil pH (0-10 cm) within a month from 6.6 with no S° to 6.1 with 50 kg·ha-1 S° and 5.8 with 100 or 150 kg·ha⁻¹ S°. The change was short-term, however, and by May of the following year, soil pH averaged 6.7, 6.5, 6.2, and 6.1 with each increasing rate of S° chemigation, respectively. The conventional treatment, in comparison, averaged 6.6 on the first date and 6.3 on the second date. In July of the following year, soil pH ranged from an average of 6.4 with no S° to 6.2 with 150 kg·ha⁻¹ S° and 5.5 with prilled S°. Soil pH declined thereafter to as low as 5.9 with additional S° chemigation and at lower depths (10-30 cm) was similar to the conventional treatment. None of the treatments had any effect on winter pruning weight in year 1 or on yield, berry weight, and plant dry weight in year 2. Chemigation with S° can be used to quickly reduce soil pH following planting and, therefore, may be a useful practice to correct high pH problems in established blueberry fields. However, it was less effective and more time consuming than applying prilled S° prior to planting. Close

• 100. [Article] The effects of nitrogen, tillage and irrigation on the color of Willamette Valley Pinot noir wine

  Various vineyard practices influence the quality of a wine. In 1999, three levels of nitrogen (N), two levels of tillage and two levels of irrigation were applied to Pinot noir grape cultivars at Benton ...

  Citation × Citation Citation Abstract Copy Title: The effects of nitrogen, tillage and irrigation on the color of Willamette Valley Pinot noir wine Author: Helms, Kelly L. Various vineyard practices influence the quality of a wine. In 1999, three levels of nitrogen (N), two levels of tillage and two levels of irrigation were applied to Pinot noir grape cultivars at Benton Lane Vineyards in the Southern Willamette Valley. N treatments were zero, soil and foliar applications. Every other row was tilled by machine. Those vines that were irrigated received 0.5 gal/hr of water for 200 hours during ripening in August. The grapes were harvested and wines were fermented from three replicates of each treatment. Spectrophotometric readings at 420nm and 520nm were used to determine the "Color Intensity" and "Hue." Ten untrained but experienced panelists rated the "Overall Color Intensity," "Purple Hue," and "Garnet Hue" of the wines using a traditional 16-point intensity scale. The panelists' intensity ratings indicated that N and irrigation had a significant effect on the Overall Color Intensity and Purple Hue of the wine. There were no significant differences in Garnet Hue intensity among the wines. The instrumental results were correlated with the panelists' ratings and clearly indicated that a direct correlation exists between the measured Color Intensity and the sensory analyses of Overall Color Intensity and Purple Hue. Soil N application and no irrigation contributed most to the high color intensity of Willamette Valley Pinot noir wine studied. Title: The effects of nitrogen, tillage and irrigation on the color of Willamette Valley Pinot noir wine Author: Helms, Kelly L. Various vineyard practices influence the quality of a wine. In 1999, three levels of nitrogen (N), two levels of tillage and two levels of irrigation were applied to Pinot noir grape cultivars at Benton Lane Vineyards in the Southern Willamette Valley. N treatments were zero, soil and foliar applications. Every other row was tilled by machine. Those vines that were irrigated received 0.5 gal/hr of water for 200 hours during ripening in August. The grapes were harvested and wines were fermented from three replicates of each treatment. Spectrophotometric readings at 420nm and 520nm were used to determine the "Color Intensity" and "Hue." Ten untrained but experienced panelists rated the "Overall Color Intensity," "Purple Hue," and "Garnet Hue" of the wines using a traditional 16-point intensity scale. The panelists' intensity ratings indicated that N and irrigation had a significant effect on the Overall Color Intensity and Purple Hue of the wine. There were no significant differences in Garnet Hue intensity among the wines. The instrumental results were correlated with the panelists' ratings and clearly indicated that a direct correlation exists between the measured Color Intensity and the sensory analyses of Overall Color Intensity and Purple Hue. Soil N application and no irrigation contributed most to the high color intensity of Willamette Valley Pinot noir wine studied. Close