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• 1. [Article] Cranberries (south coastal Oregon)

  Published July 1997. 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: Cranberries (south coastal Oregon) Author: Strik, B., Hart, J., Righetti, T., Oregon State University. Extension Service, Poole, Art Published July 1997. 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: Cranberries (south coastal Oregon) Author: Strik, B., Hart, J., Righetti, T., Oregon State University. Extension Service, Poole, Art Published July 1997. 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

• 2. [Article] Monitoring of Soil Moisture: Methods, Improving Wine Quality and Extent of Wetting

  Interim Progress Report to the Wine Advisory Board, Agricultural Research Foundation, and Participating Growers

  Citation × Citation Citation Abstract Copy Title: Monitoring of Soil Moisture: Methods, Improving Wine Quality and Extent of Wetting Author: Rojas, Wilson, Selker, John, Candolfi-Vasconcelos, M. Carmo Interim Progress Report to the Wine Advisory Board, Agricultural Research Foundation, and Participating Growers Title: Monitoring of Soil Moisture: Methods, Improving Wine Quality and Extent of Wetting Author: Rojas, Wilson, Selker, John, Candolfi-Vasconcelos, M. Carmo Interim Progress Report to the Wine Advisory Board, Agricultural Research Foundation, and Participating Growers Close

• 3. [Article] A genetic linkage map of black raspberry (Rubus occidentalis) and the mapping of Ag (4) conferring resistance to the aphid Amphorophora agathonica

  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 Springer ...

  Citation × Citation Citation Abstract Copy Title: A genetic linkage map of black raspberry (Rubus occidentalis) and the mapping of Ag (4) conferring resistance to the aphid Amphorophora agathonica Author: Finn, Chad E., Lee, Jungmin, VanBuren, Robert, Bassil, Nahla V., Bryant, Douglas W., Gilmore, Barbara S., Dossett, Michael, Mockler, Todd C., Vining, Kelly J., Bushakra, Jill M. 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 Springer and can be found at: http://link.springer.com/journal/122 Title: A genetic linkage map of black raspberry (Rubus occidentalis) and the mapping of Ag (4) conferring resistance to the aphid Amphorophora agathonica Author: Finn, Chad E., Lee, Jungmin, VanBuren, Robert, Bassil, Nahla V., Bryant, Douglas W., Gilmore, Barbara S., Dossett, Michael, Mockler, Todd C., Vining, Kelly J., Bushakra, Jill M. 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 Springer and can be found at: http://link.springer.com/journal/122 Close

• 4. [Article] Onion Thrips (Thysanoptera: Thripidae) and Their Management in the Treasure Valley of the Pacific Northwest

  Onion thrips, Thrips tabaci Lindeman and thrips-transmitted Iris yellow spot virus are the most significant pest complex affecting onion production in the Treasure Valley of eastern Oregon and southwestern ...

  Citation × Citation Citation Abstract Copy Title: Onion Thrips (Thysanoptera: Thripidae) and Their Management in the Treasure Valley of the Pacific Northwest Author: Reitz, Stuart R. Onion thrips, Thrips tabaci Lindeman and thrips-transmitted Iris yellow spot virus are the most significant pest complex affecting onion production in the Treasure Valley of eastern Oregon and southwestern Idaho. Thrips feeding damage and virus infection significantly reduce onion bulb size and economic returns for this high value crop. The high concentration of onion fields in the Treasure Valley and the long, hot, dry growing season present a number of challenges for managing onion thrips and Iris yellow spot virus (IYSV). Insecticides are the primary tool that growers have to manage this pest complex. With the long growing season, growers need to exercise good insecticide resistance management programs to maintain the effectiveness of currently available insecticides. To do this, growers need to rotate among available products and use as few applications as practical. A challenge for researchers is to determine not only which insecticides are effective but also to determine when during the season different products may be most effectively used. Techniques for analyzing field trial data are discussed, including comparing changes in pest populations before and after various insecticide applications are made. These comparisons can be made through the use of linear estimates and contrasts as part of analyses of variance, and they can aid in determining efficacy of different treatments by accounting for pre-application populations. These techniques will help researchers in developing sound sequence of insecticide applications for onion thrips management. Title: Onion Thrips (Thysanoptera: Thripidae) and Their Management in the Treasure Valley of the Pacific Northwest Author: Reitz, Stuart R. Onion thrips, Thrips tabaci Lindeman and thrips-transmitted Iris yellow spot virus are the most significant pest complex affecting onion production in the Treasure Valley of eastern Oregon and southwestern Idaho. Thrips feeding damage and virus infection significantly reduce onion bulb size and economic returns for this high value crop. The high concentration of onion fields in the Treasure Valley and the long, hot, dry growing season present a number of challenges for managing onion thrips and Iris yellow spot virus (IYSV). Insecticides are the primary tool that growers have to manage this pest complex. With the long growing season, growers need to exercise good insecticide resistance management programs to maintain the effectiveness of currently available insecticides. To do this, growers need to rotate among available products and use as few applications as practical. A challenge for researchers is to determine not only which insecticides are effective but also to determine when during the season different products may be most effectively used. Techniques for analyzing field trial data are discussed, including comparing changes in pest populations before and after various insecticide applications are made. These comparisons can be made through the use of linear estimates and contrasts as part of analyses of variance, and they can aid in determining efficacy of different treatments by accounting for pre-application populations. These techniques will help researchers in developing sound sequence of insecticide applications for onion thrips management. Close

• 5. [Article] Aquaculture Certification and the Seafood Trade

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Aquaculture Certification and the Seafood Trade Author: Lee, Daniel Abstract only. Title: Aquaculture Certification and the Seafood Trade Author: Lee, Daniel Abstract only. Close

• 6. [Article] Experimental analysis of subsurface heating and irrigation on the temperature and water content of soils

  Multiple use of waste heat from power plants may become an important consideration in the development, siting, and certification of these plants. A multiple use system of components that can beneficially ...

  Citation × Citation Citation Abstract Copy Title: Experimental analysis of subsurface heating and irrigation on the temperature and water content of soils Author: Sepaskhah, Ali Reza Multiple use of waste heat from power plants may become an important consideration in the development, siting, and certification of these plants. A multiple use system of components that can beneficially utilize waste heat may include home heating and cooling, greenhouses, animal enclosures, open basins for single cell protein production and fish farming, and open field soil warming. A subsurface irrigation-soil warming system utilizing waste heat was analyzed in this study. Thermal power plant condenser cooling water pumped through buried porous pipes was considered as a heat and water source for soil heating and subsurface irrigation. Energy is transferred from the heat source to the surrounding soil, warming it above its natural temperature. In addition, water seeping from the porous pipe prevents drying around the heat source and supplies the plant roots throughout the soil profile while avoiding the large evaporation losses at the soil surface associated with surface irrigation methods. Experiments were conducted in the laboratory to study this system. Soil was packed in containers 48 cm deep, 40 cm wide, and 4 cm thick. A heat source consisting of a copper covered electrical resistance wire was placed against one side of the box at a depth of 32 cm. A water source consisting of a porous tube was placed 2 cm above the heat source. The contained soil slab thus represented a subsurface soil warming and irrigation system with heat and water sources at depths of 32 and 30 cm respectively and a 77 cm spacing. A series of experiments was conducted with heat source temperatures of 29, 36, and 44 C, and surface heat load cycles with maxima of 0, 13, 52, and 117 watts. These experiments were repeated for Quincy, Cloquato, and Chehalis soils. The box filled with soil was saturated with water and then drained. Experiments were initiated by energizing the heat source. Temperature distributions throughout the soil profile and rates of energy dissipation were measured. Water application rates required to maintain a constant soil water content were obtained. In each experiment, water was applied at such a rate that the water content at a point near the heat source, monitored with a gamma ray attenuation system, remained constant. Apparent thermal conductivities of Quincy, Cloquato, and Chehalis soils as a function of water content were measured at 25 and 45 C by the heat probe method. The soil apparent thermal conductivity was also computed from a theoretical model based on its mineral composition, porosity, water content, and the thermal conductivity of the individual components. This model takes into account the vapor flow contribution to the apparent thermal conductivity in wet soils. Its magnitude depends on the available air-filled pore space, total porosity, and the free energy of the retained water. Predicted and experimental values of thermal conductivities showed good agreement. Soil temperature distributions were calculated using theoretical models presented in the literature. Predicted and measured isotherms showed good agreement. Energy dissipation rates as a function of soil thermal conductivity, temperature differences between heat source and soil surface, and depth and spacing of heat source were obtained. They were in agreement with those calculated from theoretical considerations. The total land area required to dissipate the waste energy from a 1000 MWe power plant operating with 34 percent efficiency was calculated for each of the three soils used in the experiments. It was found that 2841, 3714, and 4390 hectare would be required for Quincy, Cloquato, and Chehalis soils respectively. Quincy soil would require the smallest land area for this purpose because of its higher thermal conductivity. Economical and technical considerations for the installation of subsurface heating and irrigation systems require flat land close to the electrical power plant. Large areas of flat land are not always present. Subsurface irrigation replenished water lost by surface evaporation. Water use rates were obtained as a function of temperature differences between heat source and soil surface, soil type, and a range of surface heat loads. The water application rates ranged from 1.50 mm/day for Chehalis soil with a heat source temperature of 29 C in combination with the lowest surface heat load to 6.0 mm/day for Quincy soil with a heat source temperature of 44 C in combination with the highest surface heat load. These rates were adequate to prevent drying around the heat sources and supply the water needs of an actively growing crop. The effective use of this system depends on the development of suitable tubing to conduct and discharge water which could be used without clogging of the pores through which water seeps into the ground. The proposed soil warming and irrigation system does not appear to be an attractive alternative power plant cooling system. The system holds promise however as an economically attractive management system for the production of high value crops. Title: Experimental analysis of subsurface heating and irrigation on the temperature and water content of soils Author: Sepaskhah, Ali Reza Multiple use of waste heat from power plants may become an important consideration in the development, siting, and certification of these plants. A multiple use system of components that can beneficially utilize waste heat may include home heating and cooling, greenhouses, animal enclosures, open basins for single cell protein production and fish farming, and open field soil warming. A subsurface irrigation-soil warming system utilizing waste heat was analyzed in this study. Thermal power plant condenser cooling water pumped through buried porous pipes was considered as a heat and water source for soil heating and subsurface irrigation. Energy is transferred from the heat source to the surrounding soil, warming it above its natural temperature. In addition, water seeping from the porous pipe prevents drying around the heat source and supplies the plant roots throughout the soil profile while avoiding the large evaporation losses at the soil surface associated with surface irrigation methods. Experiments were conducted in the laboratory to study this system. Soil was packed in containers 48 cm deep, 40 cm wide, and 4 cm thick. A heat source consisting of a copper covered electrical resistance wire was placed against one side of the box at a depth of 32 cm. A water source consisting of a porous tube was placed 2 cm above the heat source. The contained soil slab thus represented a subsurface soil warming and irrigation system with heat and water sources at depths of 32 and 30 cm respectively and a 77 cm spacing. A series of experiments was conducted with heat source temperatures of 29, 36, and 44 C, and surface heat load cycles with maxima of 0, 13, 52, and 117 watts. These experiments were repeated for Quincy, Cloquato, and Chehalis soils. The box filled with soil was saturated with water and then drained. Experiments were initiated by energizing the heat source. Temperature distributions throughout the soil profile and rates of energy dissipation were measured. Water application rates required to maintain a constant soil water content were obtained. In each experiment, water was applied at such a rate that the water content at a point near the heat source, monitored with a gamma ray attenuation system, remained constant. Apparent thermal conductivities of Quincy, Cloquato, and Chehalis soils as a function of water content were measured at 25 and 45 C by the heat probe method. The soil apparent thermal conductivity was also computed from a theoretical model based on its mineral composition, porosity, water content, and the thermal conductivity of the individual components. This model takes into account the vapor flow contribution to the apparent thermal conductivity in wet soils. Its magnitude depends on the available air-filled pore space, total porosity, and the free energy of the retained water. Predicted and experimental values of thermal conductivities showed good agreement. Soil temperature distributions were calculated using theoretical models presented in the literature. Predicted and measured isotherms showed good agreement. Energy dissipation rates as a function of soil thermal conductivity, temperature differences between heat source and soil surface, and depth and spacing of heat source were obtained. They were in agreement with those calculated from theoretical considerations. The total land area required to dissipate the waste energy from a 1000 MWe power plant operating with 34 percent efficiency was calculated for each of the three soils used in the experiments. It was found that 2841, 3714, and 4390 hectare would be required for Quincy, Cloquato, and Chehalis soils respectively. Quincy soil would require the smallest land area for this purpose because of its higher thermal conductivity. Economical and technical considerations for the installation of subsurface heating and irrigation systems require flat land close to the electrical power plant. Large areas of flat land are not always present. Subsurface irrigation replenished water lost by surface evaporation. Water use rates were obtained as a function of temperature differences between heat source and soil surface, soil type, and a range of surface heat loads. The water application rates ranged from 1.50 mm/day for Chehalis soil with a heat source temperature of 29 C in combination with the lowest surface heat load to 6.0 mm/day for Quincy soil with a heat source temperature of 44 C in combination with the highest surface heat load. These rates were adequate to prevent drying around the heat sources and supply the water needs of an actively growing crop. The effective use of this system depends on the development of suitable tubing to conduct and discharge water which could be used without clogging of the pores through which water seeps into the ground. The proposed soil warming and irrigation system does not appear to be an attractive alternative power plant cooling system. The system holds promise however as an economically attractive management system for the production of high value crops. Close

• 7. [Image] Project history: Klamath Project, Oregon-California, 1964

  	Ill., maps (some color), photographs; Includes financial documents, organization chart, photographs, maps, water quality reports, and agricultural economics; Includes index; Title covers: calendar years ...
  	Citation × Citation Citation Abstract Copy Title: Project history: Klamath Project, Oregon-California, 1964 Author: United States. Bureau of Reclamation Year: 1964, 2008, 2006 Ill., maps (some color), photographs; Includes financial documents, organization chart, photographs, maps, water quality reports, and agricultural economics; Includes index; Title covers: calendar years for 1963-; Some issues are missing.; Description is based on: Project history: Klamath Project, Oregon-California 1963; Dates of the beginning year(s) of publication are derived from the May 1, 1903 to December 31, 1912, History of the Klamath Project and from the volume information on later volumes (v. 35) Klamath District and Klamath Project annual history for 1945, dated December 1, 1946 Title: Project history: Klamath Project, Oregon-California, 1964 Author: United States. Bureau of Reclamation Year: 1964, 2008, 2006 Ill., maps (some color), photographs; Includes financial documents, organization chart, photographs, maps, water quality reports, and agricultural economics; Includes index; Title covers: calendar years for 1963-; Some issues are missing.; Description is based on: Project history: Klamath Project, Oregon-California 1963; Dates of the beginning year(s) of publication are derived from the May 1, 1903 to December 31, 1912, History of the Klamath Project and from the volume information on later volumes (v. 35) Klamath District and Klamath Project annual history for 1945, dated December 1, 1946 Close

• 8. [Article] Predicting nitrate concentrations in leachate resulting from land application of wastewater onto various crop systems including poplars

  Land application of industrial wastewater with high levels of nitrogen requires adequate management practices to prevent groundwater pollution by nitrates. In this study a predictive computerized model ...

  Citation × Citation Citation Abstract Copy Title: Predicting nitrate concentrations in leachate resulting from land application of wastewater onto various crop systems including poplars Author: Motte, Marie Quitterie Land application of industrial wastewater with high levels of nitrogen requires adequate management practices to prevent groundwater pollution by nitrates. In this study a predictive computerized model was developed for nitrate leachate concentrations resulting from land application of wastewater onto crop systems including poplars. The study included a literature review, development of a computer program that could serve this purpose, and a field investigation to test the validity of the computed predictions. The literature review focused on poplar water and nitrogen uptakes, and suggested that mature poplars could uptake up to 400 lb of nitrogen /acre/year and 2 3 million gallons of water per acre per year. The computer model, based on 10-day water and nutrient balances, takes into account a number of parameters such as wastewater quality, evapotranspiration and precipitation data, irrigation volumes, soil water holding capacities, fertilization, crop nutrient uptakes and crop coefficients. This study involves a number of assumptions selected to give conservative (i.e., worst case approach) model predictions. Attempts to validate the model were conducted through soil and groundwater sampling along with precipitation data collection in four distinct fields in Brooks, Oregon, from October 1996 to April 1997. The variations in nitrogen soil profiles from October to April helped determine the amount of nitrogen leaving the soil, and groundwater samples from 5 feet deep wells gave nitrate concentrations in groundwater below the root zone. A sensitivity analysis of the program demonstrated how important nitrogen and water uptakes values were to the model predictions. An increase of 1% in nitrogen uptake or of 0.4% in crop coefficients generated 1% decrease in nitrogen concentration of the leachate. These results are important to consider when adopting highly uncertain literature values for crop uptakes -especially with poplars. The field validation of the model showed promising results in terms of estimating average yearly leachate concentrations in nitrogen resulting from land application of wastewater, but also suggested that more groundwater wells were needed to obtain a statistically significant validation of the model. These preliminary field results indicate that the model can provide an indication of groundwater nitrogen concentration trends but needs to further verified to be used confidently as a predictive tool. Title: Predicting nitrate concentrations in leachate resulting from land application of wastewater onto various crop systems including poplars Author: Motte, Marie Quitterie Land application of industrial wastewater with high levels of nitrogen requires adequate management practices to prevent groundwater pollution by nitrates. In this study a predictive computerized model was developed for nitrate leachate concentrations resulting from land application of wastewater onto crop systems including poplars. The study included a literature review, development of a computer program that could serve this purpose, and a field investigation to test the validity of the computed predictions. The literature review focused on poplar water and nitrogen uptakes, and suggested that mature poplars could uptake up to 400 lb of nitrogen /acre/year and 2 3 million gallons of water per acre per year. The computer model, based on 10-day water and nutrient balances, takes into account a number of parameters such as wastewater quality, evapotranspiration and precipitation data, irrigation volumes, soil water holding capacities, fertilization, crop nutrient uptakes and crop coefficients. This study involves a number of assumptions selected to give conservative (i.e., worst case approach) model predictions. Attempts to validate the model were conducted through soil and groundwater sampling along with precipitation data collection in four distinct fields in Brooks, Oregon, from October 1996 to April 1997. The variations in nitrogen soil profiles from October to April helped determine the amount of nitrogen leaving the soil, and groundwater samples from 5 feet deep wells gave nitrate concentrations in groundwater below the root zone. A sensitivity analysis of the program demonstrated how important nitrogen and water uptakes values were to the model predictions. An increase of 1% in nitrogen uptake or of 0.4% in crop coefficients generated 1% decrease in nitrogen concentration of the leachate. These results are important to consider when adopting highly uncertain literature values for crop uptakes -especially with poplars. The field validation of the model showed promising results in terms of estimating average yearly leachate concentrations in nitrogen resulting from land application of wastewater, but also suggested that more groundwater wells were needed to obtain a statistically significant validation of the model. These preliminary field results indicate that the model can provide an indication of groundwater nitrogen concentration trends but needs to further verified to be used confidently as a predictive tool. Close

• 9. [Image] Energy pricing and irrigated agriculture in the Upper Klamath Basin

  	Title from Web page (viewed on October 12, 2004).; "July 2004." ; Includes bibliographical references.
  	Citation × Citation Citation Abstract Copy Title: Energy pricing and irrigated agriculture in the Upper Klamath Basin Author: Jaeger, William K. (William Kenneth) Year: 2004, 2008, 2005 Title from Web page (viewed on October 12, 2004).; "July 2004." ; Includes bibliographical references. Title: Energy pricing and irrigated agriculture in the Upper Klamath Basin Author: Jaeger, William K. (William Kenneth) Year: 2004, 2008, 2005 Title from Web page (viewed on October 12, 2004).; "July 2004." ; Includes bibliographical references. Close

• 10. [Image] Klamath River basin : reclamation met its water bank obligations, but information provided to water bank stakeholders could be improved

  	"March 2005." ; "GAO-05-283."
  	Citation × Citation Citation Abstract Copy Title: Klamath River basin : reclamation met its water bank obligations, but information provided to water bank stakeholders could be improved Author: United States. Government Accountability Office Year: 2005 "March 2005." ; "GAO-05-283." Title: Klamath River basin : reclamation met its water bank obligations, but information provided to water bank stakeholders could be improved Author: United States. Government Accountability Office Year: 2005 "March 2005." ; "GAO-05-283." Close

• 11. [Image] Draft resource management plan/environmental impact statement for the Upper Klamath Basin

  	"March 1994."
  	Citation × Citation Citation Abstract Copy Title: Draft resource management plan/environmental impact statement for the Upper Klamath Basin Author: United States. Bureau of Land Management. Klamath Falls Resource Area Office Year: 1994, 2005 "March 1994." Title: Draft resource management plan/environmental impact statement for the Upper Klamath Basin Author: United States. Bureau of Land Management. Klamath Falls Resource Area Office Year: 1994, 2005 "March 1994." Close

• 12. [Image] Water allocation in the Klamath Reclamation Project, 2001 : an assessment of natural resource, economic, social, and institutional issues with a focus on the Upper Klamath Basin

  	"Reprinted May 2003."; Includes bibliographical references; Also available at http://eesc.oregonstate.edu/agcomwebfile/edmat/html/sr/sr1037/sr1037.html
  	Citation × Citation Citation Abstract Copy Title: Water allocation in the Klamath Reclamation Project, 2001 : an assessment of natural resource, economic, social, and institutional issues with a focus on the Upper Klamath Basin Author: Braunworth, William S. Year: 2003, 2004 "Reprinted May 2003."; Includes bibliographical references; Also available at http://eesc.oregonstate.edu/agcomwebfile/edmat/html/sr/sr1037/sr1037.html Title: Water allocation in the Klamath Reclamation Project, 2001 : an assessment of natural resource, economic, social, and institutional issues with a focus on the Upper Klamath Basin Author: Braunworth, William S. Year: 2003, 2004 "Reprinted May 2003."; Includes bibliographical references; Also available at http://eesc.oregonstate.edu/agcomwebfile/edmat/html/sr/sr1037/sr1037.html Close

• 13. [Article] Calibration of crop water use with the Penman equation under United Arab Emirates conditions

  Water shortage is one of the biggest problems facing agricultural development in the United Arab Emirates, because of the extremely arid climate and the large amount of irrigation water that is used for ...

  Citation × Citation Citation Abstract Copy Title: Calibration of crop water use with the Penman equation under United Arab Emirates conditions Author: Mohammed, Fareed H. A. N. Water shortage is one of the biggest problems facing agricultural development in the United Arab Emirates, because of the extremely arid climate and the large amount of irrigation water that is used for crops. Prediction of crop water requirements is essential to solve water management problems in this country. Two versions of the Penman equation, FAO and Wright, were used to estimate reference crop evapotranspiration from meteorological data for three regions in the U. A. E.; Northern, Central, and Eastern. Lysimeter measurements at the Northern region were provided for five crops; tomato for one season; cabbage, cucumber, and squash each for two seasons; and watermelon for three seasons. Crop evapotranspiration was estimated for these crops and related to measured crop evapotranspiration. It was found that there is great variation in measured crop evapotranspiration between seasons for individual crops, due to technical problems with the lysimeter. Combined seasons were used to calibrate the Penman equation, and the results indicated that the calibration improved the estimated crop evapotranspiration. Calibration coefficients for individual crops and for individual methods were calculated. Reference crop evapotranspiration (Etr) value for the three regions were correlated. A high correlation of estimated Etr among the three regions was found. Coefficients were developed to predict Etr at the Central and Eastern regions from the Etr at the Northern region. Title: Calibration of crop water use with the Penman equation under United Arab Emirates conditions Author: Mohammed, Fareed H. A. N. Water shortage is one of the biggest problems facing agricultural development in the United Arab Emirates, because of the extremely arid climate and the large amount of irrigation water that is used for crops. Prediction of crop water requirements is essential to solve water management problems in this country. Two versions of the Penman equation, FAO and Wright, were used to estimate reference crop evapotranspiration from meteorological data for three regions in the U. A. E.; Northern, Central, and Eastern. Lysimeter measurements at the Northern region were provided for five crops; tomato for one season; cabbage, cucumber, and squash each for two seasons; and watermelon for three seasons. Crop evapotranspiration was estimated for these crops and related to measured crop evapotranspiration. It was found that there is great variation in measured crop evapotranspiration between seasons for individual crops, due to technical problems with the lysimeter. Combined seasons were used to calibrate the Penman equation, and the results indicated that the calibration improved the estimated crop evapotranspiration. Calibration coefficients for individual crops and for individual methods were calculated. Reference crop evapotranspiration (Etr) value for the three regions were correlated. A high correlation of estimated Etr among the three regions was found. Coefficients were developed to predict Etr at the Central and Eastern regions from the Etr at the Northern region. Close

• 14. [Article] The effect of precipitation variation on soil moisture, soil nitrogen, nitrogen response and winter wheat yields in eastern Oregon

  The semi-arid regions of the Pacific Northwest are characterized by a high degree of annual temperature and precipitation variation. As a result of this climatic variation, dryland nitrogen fertilizer ...

  Citation × Citation Citation Abstract Copy Title: The effect of precipitation variation on soil moisture, soil nitrogen, nitrogen response and winter wheat yields in eastern Oregon Author: Glenn, D. M. (David Michael) The semi-arid regions of the Pacific Northwest are characterized by a high degree of annual temperature and precipitation variation. As a result of this climatic variation, dryland nitrogen fertilizer trials on fallow- ,wheat rotations typically demonstrate a variable response. Wheat growers in the area must not only cope with this climatic variation and its sundry effects upon their livelihood, they must also make decisions regarding the future level of anticipated climatic variation. The specific objectives were to: 1) develop a climatically responsive yield potential prediction model for soft white winter wheat from historical data at the Sherman Branch Experiment Station (Moro, OR); 2) modify this model for use on commercial fields; 3) field simulate five fallow-crop precipitation patterns characteristic of the variation found in the Sherman county area of eastern Oregon in order to test the yield potential model: 4) examine the effects of precipitation variation on nitrogen fertilizer responses, moisture storage and depletion and nitrogen mineralization; and 5) establish a quantitative relationship between precipitation/ soil moisture and nitrate accumulation in both the fallow and crop seasons. Two interacting regression models were developed to estimate grain yield levels in the 250-350 mm precipitation zone of eastern Oregon. The first model estimates yield potential from monthly precipitation and temperature values. The second model estimates the percent grain reduction due to delayed crop emergence. The grain yield model was adapted to commercial fields using a Productivity Index factor (PI). The PI is a measure of the productivity of other locations in relation to the Sherman Branch Experiment Station, using water-use-efficiency (WUE) as the basis of comparison. The field simulation of five fallow-crop precipitation patterns demonstrated that the maximum grain yield response occurred at 40 kg N (soil + fertilizer)/metric ton. The grain yield model demonstrated a 15% level of accuracy on a commercial field basis in both field trials and a survey of past production levels (1972-1980). It was hypothesized that the distribution of precipitation in the fallow and crop periods had an effect on both the amount and distribution of stored soil moisture. The field simulation demonstrated that more soil moisture was stored at the 90-240 cm depths by the patterns with more fallow season precipitation when measured in March of the crop year. Soil moisture storage and storage efficiencies fluctuated throughout the fallow and crop periods. At the cessation of the winter precipitation season in both the fallow and crop periods (March), the storage efficiency was highest when low levels of precipitation occurred. At this point in time, the mean crop period storage efficiency was 10% below the mean fallow period storage efficiency (34 and 44%, respectively) in both simulation studies. Soil moisture, temperature and immobilization requirements of crop residues interact to affect the net amount of nitrogen mineralization. The mineralization model proposed by Stanford and Smith (1972) was tested under field conditions. When the nitrogen immobilization requirement of the crop residues was included, the actual and predicted values were in agreement at the close of the 1978 fallow period. A nitrogen deficit was predicted at the 0-30 cm depth at the close of the 1980 fallow; however, the actual levels indicated a net accumulation of nitrate-nitrogen. Crop season mineralization, inferred from Mitscherlick and a-value extrapolations, in 1979 demonstrated that there was a decreasing amount of net mineralization during the crop season with increasing amounts of both fallow and crop season precipitation. Crop season mineralization in 1980 indicated that there was no net accumulation of nitrogen, rather a tie-up of 14 kg N/ha. This result reflects both the unsatisfied immobilization requirement predicted for the 1979 fallow season and crop season denitrification. Title: The effect of precipitation variation on soil moisture, soil nitrogen, nitrogen response and winter wheat yields in eastern Oregon Author: Glenn, D. M. (David Michael) The semi-arid regions of the Pacific Northwest are characterized by a high degree of annual temperature and precipitation variation. As a result of this climatic variation, dryland nitrogen fertilizer trials on fallow- ,wheat rotations typically demonstrate a variable response. Wheat growers in the area must not only cope with this climatic variation and its sundry effects upon their livelihood, they must also make decisions regarding the future level of anticipated climatic variation. The specific objectives were to: 1) develop a climatically responsive yield potential prediction model for soft white winter wheat from historical data at the Sherman Branch Experiment Station (Moro, OR); 2) modify this model for use on commercial fields; 3) field simulate five fallow-crop precipitation patterns characteristic of the variation found in the Sherman county area of eastern Oregon in order to test the yield potential model: 4) examine the effects of precipitation variation on nitrogen fertilizer responses, moisture storage and depletion and nitrogen mineralization; and 5) establish a quantitative relationship between precipitation/ soil moisture and nitrate accumulation in both the fallow and crop seasons. Two interacting regression models were developed to estimate grain yield levels in the 250-350 mm precipitation zone of eastern Oregon. The first model estimates yield potential from monthly precipitation and temperature values. The second model estimates the percent grain reduction due to delayed crop emergence. The grain yield model was adapted to commercial fields using a Productivity Index factor (PI). The PI is a measure of the productivity of other locations in relation to the Sherman Branch Experiment Station, using water-use-efficiency (WUE) as the basis of comparison. The field simulation of five fallow-crop precipitation patterns demonstrated that the maximum grain yield response occurred at 40 kg N (soil + fertilizer)/metric ton. The grain yield model demonstrated a 15% level of accuracy on a commercial field basis in both field trials and a survey of past production levels (1972-1980). It was hypothesized that the distribution of precipitation in the fallow and crop periods had an effect on both the amount and distribution of stored soil moisture. The field simulation demonstrated that more soil moisture was stored at the 90-240 cm depths by the patterns with more fallow season precipitation when measured in March of the crop year. Soil moisture storage and storage efficiencies fluctuated throughout the fallow and crop periods. At the cessation of the winter precipitation season in both the fallow and crop periods (March), the storage efficiency was highest when low levels of precipitation occurred. At this point in time, the mean crop period storage efficiency was 10% below the mean fallow period storage efficiency (34 and 44%, respectively) in both simulation studies. Soil moisture, temperature and immobilization requirements of crop residues interact to affect the net amount of nitrogen mineralization. The mineralization model proposed by Stanford and Smith (1972) was tested under field conditions. When the nitrogen immobilization requirement of the crop residues was included, the actual and predicted values were in agreement at the close of the 1978 fallow period. A nitrogen deficit was predicted at the 0-30 cm depth at the close of the 1980 fallow; however, the actual levels indicated a net accumulation of nitrate-nitrogen. Crop season mineralization, inferred from Mitscherlick and a-value extrapolations, in 1979 demonstrated that there was a decreasing amount of net mineralization during the crop season with increasing amounts of both fallow and crop season precipitation. Crop season mineralization in 1980 indicated that there was no net accumulation of nitrogen, rather a tie-up of 14 kg N/ha. This result reflects both the unsatisfied immobilization requirement predicted for the 1979 fallow season and crop season denitrification. Close

• 15. [Article] Lime Fertilizer Interactions Affecting Vegetable Crop Production

  p.109-119 from the 34th Annual Northwest Conference at Portland, Oregon. July 12-14, 1983.

  Citation × Citation Citation Abstract Copy Title: Lime Fertilizer Interactions Affecting Vegetable Crop Production Author: Hemphill, Delbert D., Jackson, T. L. (Thomas Lloyd), 1922- p.109-119 from the 34th Annual Northwest Conference at Portland, Oregon. July 12-14, 1983. Title: Lime Fertilizer Interactions Affecting Vegetable Crop Production Author: Hemphill, Delbert D., Jackson, T. L. (Thomas Lloyd), 1922- p.109-119 from the 34th Annual Northwest Conference at Portland, Oregon. July 12-14, 1983. Close

• 16. [Article] Air-quality and Climatic Consequences of Bioenergy Crop Cultivation

  Bioenergy is expected to play an increasingly significant role in the global energy budget. In addition to the use of liquid energy forms such as ethanol and biodiesel, electricity generation using processed ...

  Citation × Citation Citation Abstract Copy Title: Air-quality and Climatic Consequences of Bioenergy Crop Cultivation Author: Porter, William Christian Year: 2013 Bioenergy is expected to play an increasingly significant role in the global energy budget. In addition to the use of liquid energy forms such as ethanol and biodiesel, electricity generation using processed energy crops as a partial or full coal alternative is expected to increase, requiring large-scale conversions of land for the cultivation of bioenergy feedstocks such as cane, grasses, or short rotation coppice. With land-use change identified as a major contributor to changes in the emission of biogenic volatile organic compounds (BVOCs), many of which are known contributors to the pollutants ozone (O3) and fine particulate matter (PM2.5), careful review of crop emission profiles and local atmospheric chemistry will be necessary to mitigate any unintended air-quality consequences. In this work, the atmospheric consequences of bioenergy crop replacement are examined using both the high-resolution regional chemical transport model WRF/Chem (Weather Research and Forecasting with Chemistry) and the global climate model CESM (Community Earth System Model). Regional sensitivities to several representative crop types are analyzed, and the impacts of each crop on air quality and climate are compared. Overall, the high emitting crops (eucalyptus and giant reed) were found to produce climate and human health costs totaling up to 40% of the value of CO2 emissions prevented, while the related costs of the lowest-emitting crop (switchgrass) were negligible. Title: Air-quality and Climatic Consequences of Bioenergy Crop Cultivation Author: Porter, William Christian Year: 2013 Bioenergy is expected to play an increasingly significant role in the global energy budget. In addition to the use of liquid energy forms such as ethanol and biodiesel, electricity generation using processed energy crops as a partial or full coal alternative is expected to increase, requiring large-scale conversions of land for the cultivation of bioenergy feedstocks such as cane, grasses, or short rotation coppice. With land-use change identified as a major contributor to changes in the emission of biogenic volatile organic compounds (BVOCs), many of which are known contributors to the pollutants ozone (O3) and fine particulate matter (PM2.5), careful review of crop emission profiles and local atmospheric chemistry will be necessary to mitigate any unintended air-quality consequences. In this work, the atmospheric consequences of bioenergy crop replacement are examined using both the high-resolution regional chemical transport model WRF/Chem (Weather Research and Forecasting with Chemistry) and the global climate model CESM (Community Earth System Model). Regional sensitivities to several representative crop types are analyzed, and the impacts of each crop on air quality and climate are compared. Overall, the high emitting crops (eucalyptus and giant reed) were found to produce climate and human health costs totaling up to 40% of the value of CO2 emissions prevented, while the related costs of the lowest-emitting crop (switchgrass) were negligible. Close

• 17. [Article] Reducing the Negative Human-Health Impacts of Bioenergy Crop Emissions through Region-Specific Crop Selection

  An expected global increase in bioenergy-crop cultivation as an alternative to fossil fuels will have consequences on both global climate and local air quality through changes in biogenic emissions of ...

  Citation × Citation Citation Abstract Copy Title: Reducing the Negative Human-Health Impacts of Bioenergy Crop Emissions through Region-Specific Crop Selection Author: Porter, William Christian, Rosenstiel, Todd N., Guenther, Alex, Lamarque, Jean-Francois, Barsanti, Kelley Year: 2015 An expected global increase in bioenergy-crop cultivation as an alternative to fossil fuels will have consequences on both global climate and local air quality through changes in biogenic emissions of volatile organic compounds (VOCs). While greenhouse gas emissions may be reduced through the substitution of next-generation bioenergy crops such as eucalyptus, giant reed, and switchgrass for fossil fuels, the choice of species has important ramifications for human health, potentially reducing the benefits of conversion due to increases in ozone (O3) and fine particulate matter (PM2.5) levels as a result of large changes in biogenic emissions. Using the Community Earth System Model we simulate the conversion of marginal and underutilized croplands worldwide to bioenergy crops under varying future anthropogenic emissions scenarios. A conservative global replacement using high VOCemitting crop profiles leads to modeled population-weighted O3 increases of 5–27 ppb in India, 1–9 ppb in China, and 1–6 ppb in the United States, with peak PM2.5 increases of up to 2 μg m−3 . We present a metric for the regional evaluation of candidate bioenergy crops, as well as results for the application of this metric to four representative emissions profiles using four replacement scales (10–100% maximum estimated available land). Finally, we assess the total health and climate impacts of biogenic emissions, finding that the negative consequences of using high-emitting crops could exceed 50% of the positive benefits of reduced fossil fuel emissions in value. Title: Reducing the Negative Human-Health Impacts of Bioenergy Crop Emissions through Region-Specific Crop Selection Author: Porter, William Christian, Rosenstiel, Todd N., Guenther, Alex, Lamarque, Jean-Francois, Barsanti, Kelley Year: 2015 An expected global increase in bioenergy-crop cultivation as an alternative to fossil fuels will have consequences on both global climate and local air quality through changes in biogenic emissions of volatile organic compounds (VOCs). While greenhouse gas emissions may be reduced through the substitution of next-generation bioenergy crops such as eucalyptus, giant reed, and switchgrass for fossil fuels, the choice of species has important ramifications for human health, potentially reducing the benefits of conversion due to increases in ozone (O3) and fine particulate matter (PM2.5) levels as a result of large changes in biogenic emissions. Using the Community Earth System Model we simulate the conversion of marginal and underutilized croplands worldwide to bioenergy crops under varying future anthropogenic emissions scenarios. A conservative global replacement using high VOCemitting crop profiles leads to modeled population-weighted O3 increases of 5–27 ppb in India, 1–9 ppb in China, and 1–6 ppb in the United States, with peak PM2.5 increases of up to 2 μg m−3 . We present a metric for the regional evaluation of candidate bioenergy crops, as well as results for the application of this metric to four representative emissions profiles using four replacement scales (10–100% maximum estimated available land). Finally, we assess the total health and climate impacts of biogenic emissions, finding that the negative consequences of using high-emitting crops could exceed 50% of the positive benefits of reduced fossil fuel emissions in value. Close

• 18. [Article] Impacts of crop level and vine vigor on vine balance and fruit composition in Oregon Pinot noir

  Vineyard management strategies, including vineyard floor management and crop level management, can be used to influence vine vigor and fruit composition. Two studies were conducted to evaluate the impact ...

  Citation × Citation Citation Abstract Copy Title: Impacts of crop level and vine vigor on vine balance and fruit composition in Oregon Pinot noir Author: Vance, Amanda J. Vineyard management strategies, including vineyard floor management and crop level management, can be used to influence vine vigor and fruit composition. Two studies were conducted to evaluate the impact of these practices on Pinot Noir in Oregon's Willamette Valley. Managing crop levels is common in cool climate vineyard production though it is a costly practice. With economic pressures, the premium winegrape industry is questioning whether they can reduce production costs and increase yields without compromising quality. A crop thinning trial was conducted in 2010 and 2011 to address these concerns and to better understand the role of vine balance on fruit composition. Crop levels were moderately (35% crop removed) or severely (65% crop removed) thinned at pre-bloom, fruit set, lag phase, or véraison and compared to full crop treatments. In both years, crop thinning reduced yields but had no effect on berry weight or cluster size. In 2010, poor fruit set reduced overall yields, and thinning treatments resulted in very few differences in vine growth, cluster architecture or fruit composition, including total soluble solids (TSS), pH, titratable acidity (TA), yeast assimilable nitrogen (YAN), anthocyanins, phenolics and tannins. In 2011, yields were much higher due to high fruit set and larger cluster size. No differences were found in vine growth (leaf areas or pruning weights) or fruit YAN, but thinned vines had higher TSS and pH and lower TA than full crop vines at harvest. Fruit thinned at lag phase and véraison had higher TSS and lower TA than fruit thinned pre-bloom. Intensity of thinning had a stronger influence on anthocyanin and tannin concentration than timing, while phenolics were not impacted by either factor. Ravaz index values (fruit yield/pruning weight) below 2.25 and leaf area to yield ratios of 2.25 to 3.25 m²/kg improved fruit composition in 2011 as did later season thinning, though data from the remaining years of this study will provide more insight into appropriate crop load metrics for cool climate Pinot Noir. A second study was implemented in 2011 to determine the impact of crop thinning in vines with different levels of vegetative vigor caused by three vineyard floor management techniques: permanent grass (Festuca rubra spp. rubra) cover (grass), alternating grass cover and tillage (grass & tilled), and tillage of every alleyway (tilled). Crop was thinned at the BB stage of berry development (EL stage 73) to one cluster per shoot (half crop) or not thinned (full crop); all cluster wings were removed at the time of thinning. Tillage treatments had been in place four years prior to the start of the study and competition for nitrogen in grass caused reduced early season vine growth, leaf chlorophyll and canopy size at both bloom and véraison while crop thinning increased canopy size at véraison. Yields were altered by tillage and crop thinning treatments, as grass had fewer clusters per shoot and berries per cluster, and crop thinning reduced yields to 64.7% of full crop across all tillage treatments. At harvest, grass had the lowest TA while TSS and pH were not affected by tillage. Crop thinning increased TSS but did not impact pH or TA. Anthocyanins were affected by both tillage and thinning and were found to be related to vine yield, YAN, leaf N, and leaf area index. Tannins were highest in grass but were not affected by crop thinning, and phenolics were not changed by either factor. Few interactions between tillage and crop thinning were found, but as variables such as yield per vine were impacted by both treatment factors, monitoring long term effects of crop Title: Impacts of crop level and vine vigor on vine balance and fruit composition in Oregon Pinot noir Author: Vance, Amanda J. Vineyard management strategies, including vineyard floor management and crop level management, can be used to influence vine vigor and fruit composition. Two studies were conducted to evaluate the impact of these practices on Pinot Noir in Oregon's Willamette Valley. Managing crop levels is common in cool climate vineyard production though it is a costly practice. With economic pressures, the premium winegrape industry is questioning whether they can reduce production costs and increase yields without compromising quality. A crop thinning trial was conducted in 2010 and 2011 to address these concerns and to better understand the role of vine balance on fruit composition. Crop levels were moderately (35% crop removed) or severely (65% crop removed) thinned at pre-bloom, fruit set, lag phase, or véraison and compared to full crop treatments. In both years, crop thinning reduced yields but had no effect on berry weight or cluster size. In 2010, poor fruit set reduced overall yields, and thinning treatments resulted in very few differences in vine growth, cluster architecture or fruit composition, including total soluble solids (TSS), pH, titratable acidity (TA), yeast assimilable nitrogen (YAN), anthocyanins, phenolics and tannins. In 2011, yields were much higher due to high fruit set and larger cluster size. No differences were found in vine growth (leaf areas or pruning weights) or fruit YAN, but thinned vines had higher TSS and pH and lower TA than full crop vines at harvest. Fruit thinned at lag phase and véraison had higher TSS and lower TA than fruit thinned pre-bloom. Intensity of thinning had a stronger influence on anthocyanin and tannin concentration than timing, while phenolics were not impacted by either factor. Ravaz index values (fruit yield/pruning weight) below 2.25 and leaf area to yield ratios of 2.25 to 3.25 m²/kg improved fruit composition in 2011 as did later season thinning, though data from the remaining years of this study will provide more insight into appropriate crop load metrics for cool climate Pinot Noir. A second study was implemented in 2011 to determine the impact of crop thinning in vines with different levels of vegetative vigor caused by three vineyard floor management techniques: permanent grass (Festuca rubra spp. rubra) cover (grass), alternating grass cover and tillage (grass & tilled), and tillage of every alleyway (tilled). Crop was thinned at the BB stage of berry development (EL stage 73) to one cluster per shoot (half crop) or not thinned (full crop); all cluster wings were removed at the time of thinning. Tillage treatments had been in place four years prior to the start of the study and competition for nitrogen in grass caused reduced early season vine growth, leaf chlorophyll and canopy size at both bloom and véraison while crop thinning increased canopy size at véraison. Yields were altered by tillage and crop thinning treatments, as grass had fewer clusters per shoot and berries per cluster, and crop thinning reduced yields to 64.7% of full crop across all tillage treatments. At harvest, grass had the lowest TA while TSS and pH were not affected by tillage. Crop thinning increased TSS but did not impact pH or TA. Anthocyanins were affected by both tillage and thinning and were found to be related to vine yield, YAN, leaf N, and leaf area index. Tannins were highest in grass but were not affected by crop thinning, and phenolics were not changed by either factor. Few interactions between tillage and crop thinning were found, but as variables such as yield per vine were impacted by both treatment factors, monitoring long term effects of crop Close

• 19. [Article] Cover crop effects on root rot of sweet corn and soil properties

  Root rot of sweet corn in western Oregon and Washington is a significant disease that can reduce yield of intolerant cultivars of processed sweet corn by fifty percent. Root rot is caused by a complex ...

  Citation × Citation Citation Abstract Copy Title: Cover crop effects on root rot of sweet corn and soil properties Author: Miyazoe, Mikio Root rot of sweet corn in western Oregon and Washington is a significant disease that can reduce yield of intolerant cultivars of processed sweet corn by fifty percent. Root rot is caused by a complex of soilborne organisms, including Drechslera sp., Phoma terrestris, and Pythium arrhenomanes. Processors have adopted tolerant cultivars but farmers continue to seek cultural management strategies that reduce inoculum potential. High rate manure and compost amendments (16.8 - 56.0 Mg ha⁻¹) suppress root rot of corn through general suppression but this practice is not agronomically viable. General suppression is typically associated with high rates of organic amendment and high microbial (FDA) activity. Processed vegetable farmers currently grow winter cover crops to improve soil and water quality and are interested in identifying cover crops that suppress root rot of corn and increase yield. High biomass cover crops can yield up to 12 Mg ha⁻¹ dry matter; this rate of organic amendment may or may not be sufficient to generate general suppression. However, specific cover crops, such as species and cultivars of crucifers and oats, have been shown to more suppressive than other cover crop species and cultivars against specific soilborne diseases. Oat is grown as a winter cover crop in the Willamette Valley and contains avenecin, a chemical that has been shown to have activity against pathogen propagules. In addition, in previous work in containers oat cover crops suppressed root rot of sweet corn. However, there is a concern that oat cover crops immobilize N and reduce corn yield. The objectives of this research were to 1) identify high biomass cover crops with agronomic potential for western Oregon processed vegetable cropping systems, 2) evaluate the impact of high biomass cover crops on root rot severity and yield of sweet corn, 3) determine whether there is a correlation between dry matter, soil microbial activity and root rot severity and 4) determine whether cover crops immobilize nitrogen and reduce corn yield. Research station field trials were conducted in 2003-04, 2004-05 and 2005-06 at the Oregon State University vegetable research farm in Corvallis, Oregon and an on-farm experiment was conducted in 2004-05 at Kenagy Family Farm in Albany, Oregon. Oat 'Saia' winter-killed in 2005-06 and mustard mix 'Caliente' winter-killed every winter except 2004-05, when winter temperatures never dropped below -7 °C. Rape 'Dwarf Essex', mustard 'Braco', and arugula are reliably winter-hardy. All mustard cover crop species are susceptible to white mold caused by Sclerotinia sclerotiorum, causal agent of white mold of snap bean. Oat (Avena sativa) is susceptible to barley yellow dwarf virus (BYDV), an important pathogen of grass seed crops. Mustard cover crops could contaminate cruciferous seed crops. All of the cover crop species evaluated demonstrated some potential to suppress root rot of corn. Oat 'Saia' was the most consistently suppressive; it suppressed root rot in 4 of 6 experiments. Sudangrass was suppressive in the only year it was evaluated as well as in container experiments in previous work. In general, cover crops increased or had no impact on shoot and root dry matter in greenhouse bioassays. There was only one significant cover crop treatment effect on yield; in 2006, the oat treatment increased yield by 11.6% compared to the fallow. Overall, cover crop aboveground dry matter (DM) ranged from 4.2 Mg ha⁻¹ (summer R 2003) to 12.2 Mg ha⁻¹ (winter O 2004). Overall, there was a significant relationship between cover crop DM and radicle rot severity in greenhouse bioassay but not in field experiment. Cover crop treatments consistently increased soil microbial activity. Overall, there was a significant negative correlation between microbial activity and root rot severity in greenhouse bioassays early after cover crop incorporation, but the correlation weakened over time and ultimately was lost by about 80 days after incorporation. The C:N of oat and rape residues was 51 and 21, respectively. Soil nitrogen was immobilized by both the oat and rape cover crops, but oat immobilized more N than rape. Corn grown in the oat treatment soils had lower SPAD values, but it is not clear whether foliar N was sufficiently low to reduce yield potential. There was no consistent trend in above- or below-ground corn dry matter after oat incorporation over the three years. In 2006, the oat treatment had no significant effect on corn DM but increased yield by 11.1%. More work is required to better understand the impact of oat cover crop N immobilization on corn N status and yield. Oat 'Saia' has the potential to suppress root rot of sweet corn and maintain or increase corn productivity. However, this oat cultivar is not reliably winter-hardy and is susceptible to BYDV. Future research should screen Avena species and/or cultivars for improved winter hardiness, BYDV resistance, and root rot suppressive potential. Title: Cover crop effects on root rot of sweet corn and soil properties Author: Miyazoe, Mikio Root rot of sweet corn in western Oregon and Washington is a significant disease that can reduce yield of intolerant cultivars of processed sweet corn by fifty percent. Root rot is caused by a complex of soilborne organisms, including Drechslera sp., Phoma terrestris, and Pythium arrhenomanes. Processors have adopted tolerant cultivars but farmers continue to seek cultural management strategies that reduce inoculum potential. High rate manure and compost amendments (16.8 - 56.0 Mg ha⁻¹) suppress root rot of corn through general suppression but this practice is not agronomically viable. General suppression is typically associated with high rates of organic amendment and high microbial (FDA) activity. Processed vegetable farmers currently grow winter cover crops to improve soil and water quality and are interested in identifying cover crops that suppress root rot of corn and increase yield. High biomass cover crops can yield up to 12 Mg ha⁻¹ dry matter; this rate of organic amendment may or may not be sufficient to generate general suppression. However, specific cover crops, such as species and cultivars of crucifers and oats, have been shown to more suppressive than other cover crop species and cultivars against specific soilborne diseases. Oat is grown as a winter cover crop in the Willamette Valley and contains avenecin, a chemical that has been shown to have activity against pathogen propagules. In addition, in previous work in containers oat cover crops suppressed root rot of sweet corn. However, there is a concern that oat cover crops immobilize N and reduce corn yield. The objectives of this research were to 1) identify high biomass cover crops with agronomic potential for western Oregon processed vegetable cropping systems, 2) evaluate the impact of high biomass cover crops on root rot severity and yield of sweet corn, 3) determine whether there is a correlation between dry matter, soil microbial activity and root rot severity and 4) determine whether cover crops immobilize nitrogen and reduce corn yield. Research station field trials were conducted in 2003-04, 2004-05 and 2005-06 at the Oregon State University vegetable research farm in Corvallis, Oregon and an on-farm experiment was conducted in 2004-05 at Kenagy Family Farm in Albany, Oregon. Oat 'Saia' winter-killed in 2005-06 and mustard mix 'Caliente' winter-killed every winter except 2004-05, when winter temperatures never dropped below -7 °C. Rape 'Dwarf Essex', mustard 'Braco', and arugula are reliably winter-hardy. All mustard cover crop species are susceptible to white mold caused by Sclerotinia sclerotiorum, causal agent of white mold of snap bean. Oat (Avena sativa) is susceptible to barley yellow dwarf virus (BYDV), an important pathogen of grass seed crops. Mustard cover crops could contaminate cruciferous seed crops. All of the cover crop species evaluated demonstrated some potential to suppress root rot of corn. Oat 'Saia' was the most consistently suppressive; it suppressed root rot in 4 of 6 experiments. Sudangrass was suppressive in the only year it was evaluated as well as in container experiments in previous work. In general, cover crops increased or had no impact on shoot and root dry matter in greenhouse bioassays. There was only one significant cover crop treatment effect on yield; in 2006, the oat treatment increased yield by 11.6% compared to the fallow. Overall, cover crop aboveground dry matter (DM) ranged from 4.2 Mg ha⁻¹ (summer R 2003) to 12.2 Mg ha⁻¹ (winter O 2004). Overall, there was a significant relationship between cover crop DM and radicle rot severity in greenhouse bioassay but not in field experiment. Cover crop treatments consistently increased soil microbial activity. Overall, there was a significant negative correlation between microbial activity and root rot severity in greenhouse bioassays early after cover crop incorporation, but the correlation weakened over time and ultimately was lost by about 80 days after incorporation. The C:N of oat and rape residues was 51 and 21, respectively. Soil nitrogen was immobilized by both the oat and rape cover crops, but oat immobilized more N than rape. Corn grown in the oat treatment soils had lower SPAD values, but it is not clear whether foliar N was sufficiently low to reduce yield potential. There was no consistent trend in above- or below-ground corn dry matter after oat incorporation over the three years. In 2006, the oat treatment had no significant effect on corn DM but increased yield by 11.1%. More work is required to better understand the impact of oat cover crop N immobilization on corn N status and yield. Oat 'Saia' has the potential to suppress root rot of sweet corn and maintain or increase corn productivity. However, this oat cultivar is not reliably winter-hardy and is susceptible to BYDV. Future research should screen Avena species and/or cultivars for improved winter hardiness, BYDV resistance, and root rot suppressive potential. Close

• 20. [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

• 21. [Article] The effect of precipitation variation and fertilization level on the nutritive value of wheat residue

  Five simulated precipitation patterns characteristic of the Columbia Basin and Plateau region and six fertilization rates were evaluated for their effect on percent crude protein, percent in vitro dry ...

  Citation × Citation Citation Abstract Copy Title: The effect of precipitation variation and fertilization level on the nutritive value of wheat residue Author: Carey, Anne C. Five simulated precipitation patterns characteristic of the Columbia Basin and Plateau region and six fertilization rates were evaluated for their effect on percent crude protein, percent in vitro dry matter digestibility, fiber content, and yield of wheat aftermath on a commercial farm in north central Oregon. The higher moisture regimes showed the greatest increase in percent crude protein with increasing nitrogen fertilizer levels. Chaff and straw values were significantly higher for the dry fallow-normal crop precipitation pattern than for normal fallow-dry crop pattern and significantly higher for the wet fallow-normal crop pattern than for normal fallow-wet crop. Percent in vitro dry matter digestibility also increased under the high moisture precipitation patterns and there was a positive relationship between fertilization level and digestibility. The digestibility values for chaff and straw were higher for the dry fallow-normal crop precipitation regime over the normal fallow-dry crop only at the higher fertilization levels. Examination of wet fallow-normal crop vs. normal fallow-wet crop showed increased digestibility for the pattern receiving more moisture in the fallow period, also at only the higher fertilization levels. This study indicated that higher moisture regimes resulted in increased straw and chaff yields. Although not significant for every precipitation pattern, there was indication of a positive relationship between fertilization level and straw and chaff yields. For both straw and chaff yield, no difference was seen when comparing dry fallow-normal crop and normal fallow-dry crop regimes. Testing wet fallow-normal crop vs. normal fallow-wet crop patterns revealed increased chaff yields at higher fertilization levels under the pattern receiving less moisture in the fallow period, but increased straw yields at higher fertilization levels under the pattern receiving more moisture in the fallow period. Percentages of acid detergent fiber, lignin, and cellulose were not significantly affected by precipitation variation or level of fertilization. The fertilization by precipitation pattern interaction was not a significant source of variation, with the exception of percentage crude protein of wheat straw in the first year. Title: The effect of precipitation variation and fertilization level on the nutritive value of wheat residue Author: Carey, Anne C. Five simulated precipitation patterns characteristic of the Columbia Basin and Plateau region and six fertilization rates were evaluated for their effect on percent crude protein, percent in vitro dry matter digestibility, fiber content, and yield of wheat aftermath on a commercial farm in north central Oregon. The higher moisture regimes showed the greatest increase in percent crude protein with increasing nitrogen fertilizer levels. Chaff and straw values were significantly higher for the dry fallow-normal crop precipitation pattern than for normal fallow-dry crop pattern and significantly higher for the wet fallow-normal crop pattern than for normal fallow-wet crop. Percent in vitro dry matter digestibility also increased under the high moisture precipitation patterns and there was a positive relationship between fertilization level and digestibility. The digestibility values for chaff and straw were higher for the dry fallow-normal crop precipitation regime over the normal fallow-dry crop only at the higher fertilization levels. Examination of wet fallow-normal crop vs. normal fallow-wet crop showed increased digestibility for the pattern receiving more moisture in the fallow period, also at only the higher fertilization levels. This study indicated that higher moisture regimes resulted in increased straw and chaff yields. Although not significant for every precipitation pattern, there was indication of a positive relationship between fertilization level and straw and chaff yields. For both straw and chaff yield, no difference was seen when comparing dry fallow-normal crop and normal fallow-dry crop regimes. Testing wet fallow-normal crop vs. normal fallow-wet crop patterns revealed increased chaff yields at higher fertilization levels under the pattern receiving less moisture in the fallow period, but increased straw yields at higher fertilization levels under the pattern receiving more moisture in the fallow period. Percentages of acid detergent fiber, lignin, and cellulose were not significantly affected by precipitation variation or level of fertilization. The fertilization by precipitation pattern interaction was not a significant source of variation, with the exception of percentage crude protein of wheat straw in the first year. Close

• 22. [Article] Weed control in nursery field production

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

  Citation × Citation Citation Abstract Copy Title: Weed control in nursery field production Author: Altland, James Elmer, 1973-, Oregon State University. Extension Service Published November 2005. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Weed control in nursery field production Author: Altland, James Elmer, 1973-, Oregon State University. Extension Service Published November 2005. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 23. [Article] An ecosystem service approach to inform reactive nitrogen management in the lower Yakima River Basin, Washington

  Spatially explicit ecosystem service valuation (ESV) allows for the identification of the location and magnitude of services provided by natural ecosystems to human activities along with a measure of their ...

  Citation × Citation Citation Abstract Copy Title: An ecosystem service approach to inform reactive nitrogen management in the lower Yakima River Basin, Washington Author: Crowell, Morgan Spatially explicit ecosystem service valuation (ESV) allows for the identification of the location and magnitude of services provided by natural ecosystems to human activities along with a measure of their significance based upon economic valuation. While ESV has been used to provide new insight into land use management, few studies have identified the connections between the values of ecosystem services and ecological sensitivity to nitrogen loading despite a growing body of ecosystem service literature. This research combines a GIS-based, value transfer approach to map ecosystem services in the Lower Yakima River Basin (LYRB), Washington, USA, along with estimates of nitrogen loading to identify how nitrogen management may affect ecosystem services in the basin. This analysis combines values of ecosystem services with estimates of nitrogen loading and identifies subwatersheds and specific parcels within a Groundwater Management Area (GWMA) most susceptible to reductions in ecosystem services due to excess nitrogen loading. Based on the benefit transfer analysis, wetlands and forested areas have disproportionately high values of ecosystem services when compared to their land area in the LYRB, while pasture and cultivated crops contribute much less to the total value of ecosystem service flows in proportion to the total area in the LYRB. Across the study area estimated nitrogen loads are strongly driven by the location of concentrated animal feeding operations (CAFOs) and cultivated crops. Areas of particularly high nitrogen loading and high ESV may highlight specific areas for achieving immediate success in increasing or maintaining ecosystem services through appropriately focused regulatory mechanisms. The land cover analysis however, completely neglects the values and importance of subsurface processes and groundwater resources in ecosystem service assessment, and therefore an econometric model is applied to estimate willingness to pay (WTP) to maintain safe nitrate levels in private wells. Through the incorporation of WTP estimates for groundwater quality, a more complete economic and ecological perspective on the effects of landscape N loading in the study site is highlighted. The results of these estimates clearly indicate that ecosystem services from groundwater should be considered to have significant value in the LYRB. Further economic valuation data on specific land cover types and the value of groundwater quality, whether from primary studies or meta-analysis, is needed to refine relative measures of ecosystem service values and more confidently describe these values in specific dollar amounts. Additionally, limits in spatial data resolution may contribute to errors in location and magnitude of ecosystem services, and is an area in need of further development. Despite these potential limitations, this analysis highlights a promising direction for combining spatially explicit ecosystem service valuation with nutrient loading data to identify the location and potential magnitude of effects on ecosystem services from management practices. Title: An ecosystem service approach to inform reactive nitrogen management in the lower Yakima River Basin, Washington Author: Crowell, Morgan Spatially explicit ecosystem service valuation (ESV) allows for the identification of the location and magnitude of services provided by natural ecosystems to human activities along with a measure of their significance based upon economic valuation. While ESV has been used to provide new insight into land use management, few studies have identified the connections between the values of ecosystem services and ecological sensitivity to nitrogen loading despite a growing body of ecosystem service literature. This research combines a GIS-based, value transfer approach to map ecosystem services in the Lower Yakima River Basin (LYRB), Washington, USA, along with estimates of nitrogen loading to identify how nitrogen management may affect ecosystem services in the basin. This analysis combines values of ecosystem services with estimates of nitrogen loading and identifies subwatersheds and specific parcels within a Groundwater Management Area (GWMA) most susceptible to reductions in ecosystem services due to excess nitrogen loading. Based on the benefit transfer analysis, wetlands and forested areas have disproportionately high values of ecosystem services when compared to their land area in the LYRB, while pasture and cultivated crops contribute much less to the total value of ecosystem service flows in proportion to the total area in the LYRB. Across the study area estimated nitrogen loads are strongly driven by the location of concentrated animal feeding operations (CAFOs) and cultivated crops. Areas of particularly high nitrogen loading and high ESV may highlight specific areas for achieving immediate success in increasing or maintaining ecosystem services through appropriately focused regulatory mechanisms. The land cover analysis however, completely neglects the values and importance of subsurface processes and groundwater resources in ecosystem service assessment, and therefore an econometric model is applied to estimate willingness to pay (WTP) to maintain safe nitrate levels in private wells. Through the incorporation of WTP estimates for groundwater quality, a more complete economic and ecological perspective on the effects of landscape N loading in the study site is highlighted. The results of these estimates clearly indicate that ecosystem services from groundwater should be considered to have significant value in the LYRB. Further economic valuation data on specific land cover types and the value of groundwater quality, whether from primary studies or meta-analysis, is needed to refine relative measures of ecosystem service values and more confidently describe these values in specific dollar amounts. Additionally, limits in spatial data resolution may contribute to errors in location and magnitude of ecosystem services, and is an area in need of further development. Despite these potential limitations, this analysis highlights a promising direction for combining spatially explicit ecosystem service valuation with nutrient loading data to identify the location and potential magnitude of effects on ecosystem services from management practices. Close

• 24. [Article] Establishment of grass seed crops with cereal companion crops

  In conventional cropping systems in the Willamette Valley, slow establishing grass species, such as Kentucky bluegrass (Poapratensis L.) are planted in the spring and seed is not harvested until the following ...

  Citation × Citation Citation Abstract Copy Title: Establishment of grass seed crops with cereal companion crops Author: DeHaas, Jeroen A. M. In conventional cropping systems in the Willamette Valley, slow establishing grass species, such as Kentucky bluegrass (Poapratensis L.) are planted in the spring and seed is not harvested until the following year. Due to increasing annual production costs, it is necessary to generate a cash return from each field each production year. This can be achieved by establishing the grass seed crop with a cereal companion crop either in fall or spring. The objective of this study was to identify the suitability of establishing grass seed crops with cereal companion crops in the Willamette Valley. To realize this objective, combinations of companion crop species, seeding rates, planting arrangements and grass species were examined for suitability in a companion cropping system. In addition, competitive effects of the companion crop on undersown grasses were studied. Three field experiments were conducted at two locations in the Willamette Valley over a two-year period (1980-1982). Percent light transmittance was measured in companion crop canopies developed under different seeding rates (67.2 and 100.8 kg/ha) and planting arrangements (parallel with and across grass rows) and in different types of companion crops (winter wheat, spring wheat and spring barley). Soil water potential was determined to investigate moisture patterns due to crop competition. Tiller samples were taken from undersown grasses and from these samples the following growth parameters were determined: tiller number, tiller height, leaf weight and leaf area per tiller, Specific Leaf Weight (SLW), and Leaf Area Index (LAI). Companion crop and grass seed yields were determined to obtain information for the economic feasibility of the companion cropping system. Parallel planting of the grass and companion crops gave higher light transmittance values than cross planting. However, no beneficial effects on grass crop growth parameters were detected. Companion crop seeding rates did not result in different percent light transmittance values, or was there an effect on growth parameters of undersown Kentucky bluegrass and orchardgrass (Dactylis glomerata L.). Soil water potential was higher in Kentucky bluegrass plots established with a companion crop at Gervais than in plots established without a companion crop. Tiller number for Kentucky bluegrass was suppressed by the companion crop for the experiment in Gervais. Tiller number and LAI for Kentucky bluegrass and orchardgrass was lower when established with a companion crop in the fall of 1981 at Hyslop Farm. Tiller height, leaf weight and leaf area per tiller of Kentucky bluegrass was higher when established with a wheat companion crop at Gervais. Leaf weight per tiller and SLW of orchardgrass were suppressed by the wheat companion crop at Hyslop Farm. Differential effects on growth parameters due to different companion crops were not detected. Low companion crop yields did not offset a lower subsequent Bristol Kentucky bluegrass seed yield in Gervais. This resulted in a lower mean annual gross return for the bluegrass seed crop when established with a companion crop. Wheat companion crop yields were approximately 10,000 kg/ha and 6,300 kg/ha when planted with Kentucky bluegrass and orchardgrass, respectively, at Hyslop Farm. Grass seed yields were not obtained for this study due to time constraints. Further investigation is needed to study the effect of companion crop planting arrangements on undersown grasses. The necessity of irrigation and nitrogen fertilization immediately after companion crop harvest for companion cropping systems in the Willamette Valley also need to be further investigated. Title: Establishment of grass seed crops with cereal companion crops Author: DeHaas, Jeroen A. M. In conventional cropping systems in the Willamette Valley, slow establishing grass species, such as Kentucky bluegrass (Poapratensis L.) are planted in the spring and seed is not harvested until the following year. Due to increasing annual production costs, it is necessary to generate a cash return from each field each production year. This can be achieved by establishing the grass seed crop with a cereal companion crop either in fall or spring. The objective of this study was to identify the suitability of establishing grass seed crops with cereal companion crops in the Willamette Valley. To realize this objective, combinations of companion crop species, seeding rates, planting arrangements and grass species were examined for suitability in a companion cropping system. In addition, competitive effects of the companion crop on undersown grasses were studied. Three field experiments were conducted at two locations in the Willamette Valley over a two-year period (1980-1982). Percent light transmittance was measured in companion crop canopies developed under different seeding rates (67.2 and 100.8 kg/ha) and planting arrangements (parallel with and across grass rows) and in different types of companion crops (winter wheat, spring wheat and spring barley). Soil water potential was determined to investigate moisture patterns due to crop competition. Tiller samples were taken from undersown grasses and from these samples the following growth parameters were determined: tiller number, tiller height, leaf weight and leaf area per tiller, Specific Leaf Weight (SLW), and Leaf Area Index (LAI). Companion crop and grass seed yields were determined to obtain information for the economic feasibility of the companion cropping system. Parallel planting of the grass and companion crops gave higher light transmittance values than cross planting. However, no beneficial effects on grass crop growth parameters were detected. Companion crop seeding rates did not result in different percent light transmittance values, or was there an effect on growth parameters of undersown Kentucky bluegrass and orchardgrass (Dactylis glomerata L.). Soil water potential was higher in Kentucky bluegrass plots established with a companion crop at Gervais than in plots established without a companion crop. Tiller number for Kentucky bluegrass was suppressed by the companion crop for the experiment in Gervais. Tiller number and LAI for Kentucky bluegrass and orchardgrass was lower when established with a companion crop in the fall of 1981 at Hyslop Farm. Tiller height, leaf weight and leaf area per tiller of Kentucky bluegrass was higher when established with a wheat companion crop at Gervais. Leaf weight per tiller and SLW of orchardgrass were suppressed by the wheat companion crop at Hyslop Farm. Differential effects on growth parameters due to different companion crops were not detected. Low companion crop yields did not offset a lower subsequent Bristol Kentucky bluegrass seed yield in Gervais. This resulted in a lower mean annual gross return for the bluegrass seed crop when established with a companion crop. Wheat companion crop yields were approximately 10,000 kg/ha and 6,300 kg/ha when planted with Kentucky bluegrass and orchardgrass, respectively, at Hyslop Farm. Grass seed yields were not obtained for this study due to time constraints. Further investigation is needed to study the effect of companion crop planting arrangements on undersown grasses. The necessity of irrigation and nitrogen fertilization immediately after companion crop harvest for companion cropping systems in the Willamette Valley also need to be further investigated. Close

• 25. [Article] Evaluation of four quality factors in a selected winter x spring wheat cross (Triticum aestivum Vill., Host)

  The nature of the genetic variation associated with a cross involving winter and spring wheat parents for four quality factors was evaluated. Yamhill, a soft white winter wheat, and Inia 66, a hard red ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of four quality factors in a selected winter x spring wheat cross (Triticum aestivum Vill., Host) Author: Schumaker, Karen Sue The nature of the genetic variation associated with a cross involving winter and spring wheat parents for four quality factors was evaluated. Yamhill, a soft white winter wheat, and Inia 66, a hard red spring wheat, were selected as parents for this study. They represented distinctly different phenotypes for the attributes measured. Parents, F₁, F₂ and reciprocal backcrosses were examined for protein and lysine content, kernel hardness, and sedimentation value. Significant differences were observed between the two parents for protein content. The F₁ mean was lower than the low protein parent with the F₂ mean intermediate between the two parents. This latter factor plus a high narrow sense heritability estimate suggest that the genetic variation associated with protein content was largely due to genes which act in an additive manner. Backcrosses to either parent shifted the population toward the mean of the recurrent parent. Transgressive segregation was observed in the F₂ for both low and high protein content suggesting that selection for this trait should be effective in early generations. Parents differed significantly for lysine content with the winter parent, Yamhill displaying lysine values approaching the highest previously reported for wheat. Intermediate F₁ and F₂ population means and a high narrow sense heritability estimate suggest the genes involved function in an additive manner. The backcross progeny to Yamhill had a mean value approaching that of the recurrent parent. No transgressive segregation was observed in the F₂ for lysine content higher than Yamhill. It appears that lysine content in this cross is qualitatively inherited and that selection for improved lysine content above Yamhill appears limited. The genetic variation associated with kernel hardness appears to be largely additive with F₁ and F₂ means intermediate between the two parents and a high narrow sense heritability estimate. Transgressive segregation was observed in the F₂ generation for both soft and hard kernel types. Selection for this trait should be effective in early generations. Significant differences were observed for the parental types for sedimentation value. The F₁ and F₂ means were below the midparent value. No transgressive segregation was observed in the F₂ for either low or high sedimentation value. One backcross to the low sedimentation parent brought the population back to the low parent mean. One backcross to the high sedimentation parent shifted the population toward the recurrent parent but no individuals were recovered that approached the high parent. From this study it appears that selection for high sedimentation value types would be very difficult. Evidence provided in this study supports the concept that winter x spring crosses can provide useable genetic variation for desirable quality factors. Title: Evaluation of four quality factors in a selected winter x spring wheat cross (Triticum aestivum Vill., Host) Author: Schumaker, Karen Sue The nature of the genetic variation associated with a cross involving winter and spring wheat parents for four quality factors was evaluated. Yamhill, a soft white winter wheat, and Inia 66, a hard red spring wheat, were selected as parents for this study. They represented distinctly different phenotypes for the attributes measured. Parents, F₁, F₂ and reciprocal backcrosses were examined for protein and lysine content, kernel hardness, and sedimentation value. Significant differences were observed between the two parents for protein content. The F₁ mean was lower than the low protein parent with the F₂ mean intermediate between the two parents. This latter factor plus a high narrow sense heritability estimate suggest that the genetic variation associated with protein content was largely due to genes which act in an additive manner. Backcrosses to either parent shifted the population toward the mean of the recurrent parent. Transgressive segregation was observed in the F₂ for both low and high protein content suggesting that selection for this trait should be effective in early generations. Parents differed significantly for lysine content with the winter parent, Yamhill displaying lysine values approaching the highest previously reported for wheat. Intermediate F₁ and F₂ population means and a high narrow sense heritability estimate suggest the genes involved function in an additive manner. The backcross progeny to Yamhill had a mean value approaching that of the recurrent parent. No transgressive segregation was observed in the F₂ for lysine content higher than Yamhill. It appears that lysine content in this cross is qualitatively inherited and that selection for improved lysine content above Yamhill appears limited. The genetic variation associated with kernel hardness appears to be largely additive with F₁ and F₂ means intermediate between the two parents and a high narrow sense heritability estimate. Transgressive segregation was observed in the F₂ generation for both soft and hard kernel types. Selection for this trait should be effective in early generations. Significant differences were observed for the parental types for sedimentation value. The F₁ and F₂ means were below the midparent value. No transgressive segregation was observed in the F₂ for either low or high sedimentation value. One backcross to the low sedimentation parent brought the population back to the low parent mean. One backcross to the high sedimentation parent shifted the population toward the recurrent parent but no individuals were recovered that approached the high parent. From this study it appears that selection for high sedimentation value types would be very difficult. Evidence provided in this study supports the concept that winter x spring crosses can provide useable genetic variation for desirable quality factors. Close

• 26. [Article] Enhancement of the weed competitive ability of lowland rice (Oryza sativa L.) cultivars

  Most of the presently grown cultivars of rice (Oryza sativa L.) have poor competitive ability against weeds if compared with traditional cultivars. Therefore, effective weed control is an important but ...

  Citation × Citation Citation Abstract Copy Title: Enhancement of the weed competitive ability of lowland rice (Oryza sativa L.) cultivars Author: Ranasinghe, Lakshman L. Most of the presently grown cultivars of rice (Oryza sativa L.) have poor competitive ability against weeds if compared with traditional cultivars. Therefore, effective weed control is an important but often costly and difficult management practice in rice crop production. If weed competitive ability of rice cultivars could be improved by changing the plant morphology and some agronomic practices, crop losses and the cost of weed control in rice production would be reduced. Three field experiments were conducted to identify weed competitive morphological traits of rice and to evaluate the effect of delaying starter fertilizer application on weed competition in rice. The nature of rice-barnyardgrass competition varies greatly with rice cultivar morphology. In an addition series experiment, the semi-dwarf, erect leaved, high yielding cultivar BG 350, which possesses much of the plant characteristics required for a high yield was affected much more than the cultivar BG 94-2, which has a tall stature, high leaf area index and good seedling vigor. In the varietal testing experiment, as predicted by the sensitivity analysis, cultivars with rapid height growth, high leaf area growth and plant dry weight increase during seedling stage, height and leaf area at maturity were associated with high competitive ability. The weed competitive ability of tested cultivars varied from relatively high in cultivars PPL and BG 94-2, moderate in BW 267-3 to poor in BG 1611 and BG 350. The delay of starter fertilizer application by 14 days in cultivar BG 350 improved its competitive ability against barnyardgrass (BYG). Under BYG competition, a 14-day delay of starter fertilizer application reduced the percent crop loss by weed competition 6.64 and 22.99% under the normal planting density in the Maha and Yala cultivation seasons, respectively. The crop-weed competition model INTERCOM simulated yield losses for the tested cultivars followed the trends observed in field experiments. However the simulated values were always higher than the observed values. Title: Enhancement of the weed competitive ability of lowland rice (Oryza sativa L.) cultivars Author: Ranasinghe, Lakshman L. Most of the presently grown cultivars of rice (Oryza sativa L.) have poor competitive ability against weeds if compared with traditional cultivars. Therefore, effective weed control is an important but often costly and difficult management practice in rice crop production. If weed competitive ability of rice cultivars could be improved by changing the plant morphology and some agronomic practices, crop losses and the cost of weed control in rice production would be reduced. Three field experiments were conducted to identify weed competitive morphological traits of rice and to evaluate the effect of delaying starter fertilizer application on weed competition in rice. The nature of rice-barnyardgrass competition varies greatly with rice cultivar morphology. In an addition series experiment, the semi-dwarf, erect leaved, high yielding cultivar BG 350, which possesses much of the plant characteristics required for a high yield was affected much more than the cultivar BG 94-2, which has a tall stature, high leaf area index and good seedling vigor. In the varietal testing experiment, as predicted by the sensitivity analysis, cultivars with rapid height growth, high leaf area growth and plant dry weight increase during seedling stage, height and leaf area at maturity were associated with high competitive ability. The weed competitive ability of tested cultivars varied from relatively high in cultivars PPL and BG 94-2, moderate in BW 267-3 to poor in BG 1611 and BG 350. The delay of starter fertilizer application by 14 days in cultivar BG 350 improved its competitive ability against barnyardgrass (BYG). Under BYG competition, a 14-day delay of starter fertilizer application reduced the percent crop loss by weed competition 6.64 and 22.99% under the normal planting density in the Maha and Yala cultivation seasons, respectively. The crop-weed competition model INTERCOM simulated yield losses for the tested cultivars followed the trends observed in field experiments. However the simulated values were always higher than the observed values. Close

• 27. [Article] The agronomic, economic and social effects of the availability of new weed control treatments to small corn farmers in the North Atlantic Zone of Costa Rica

  The North Atlantic zone of Costa Rica is an alluvial plain, whose fairly good soils and warm, extremely wet climate generate serious weed problems in cultivated crops and pastureland. Basic foods - corn, ...

  Citation × Citation Citation Abstract Copy Title: The agronomic, economic and social effects of the availability of new weed control treatments to small corn farmers in the North Atlantic Zone of Costa Rica Author: McCarty, Thomas Vere The North Atlantic zone of Costa Rica is an alluvial plain, whose fairly good soils and warm, extremely wet climate generate serious weed problems in cultivated crops and pastureland. Basic foods - corn, beans, rice and yuca - are important small farm crops. New land is still being opened for small farming, encouraged by a government-sponsored homesteading program. Research was initiated in 1976 by the International Plant Protection Center, in cooperation with CATIE, to determine whether the weed control practices currently used by small farmers could be improved. Agronomic results indicate that tilling the soil gives no advantage over the farmers present no-tillage methods. Pre-plant treatments with the herbicides glyphosate and paraquat have been shown to save labor in corn crops. There is little evidence that the new treatments raise corn yields. A survey of small farmers was conducted in the region in 1977 and 1978. A random sample of 21 farmers were selected for interviews. The information included a general description of each farm family and the complete farm operation and detailed descriptions of cultural practices in corn and beans crop, with special emphasis on weed control. Social and economic information was also obtained. Small farms in the sample are in various stages of development. The first step is usually to brush out the native timberland and fence off areas for a few cattle to graze. Then parcels are cleared for annual crops, especially corn, which is the most dependable cash crop. The farmer rotates parcels for annual crops, weedy fallow and pasture. He constantly attempts to build up his beef herd. Development of perennial plots is limited by the quantities demanded for home and local use. Nearly half the labor, and half the cash resources, expended in corn production are for weed control. The farmers typically cut the weeds with machete and leave the vegetation as mulch before planting, weed the crop with machete or with very light applications of 2,4-D, and cut the weeds once more with machete before doubling the ears and harvesting. Some temporary local shortages of labor occur in the peak periods, when harvesting for one season overlaps with soil preparation and planting for the next, although general underemployment prevails in the long slack periods. Weed conditions influence greatly the quantities of labor used for weed control. Rottboellia exaltata is the most noxious weed in corn cropping. The quantitative information from the survey was tabulated in partial budgets or detailed accounting sheets of variable costs and revenues, for corn parcels on each sample farm. Analysis of variance and regression models were used to test hypothetical relationships among the variables. These results were then compared with estimated capabilities and costs of the experimental weed control treatments for the corn crop on each sample farm. Reported wage rates and calculated returns to family labor were used to estimate the values of family labor. It was found that a minority of the small corn farmers - those who currently use relatively high quantities of cash resources - might be able to reduce costs with the new treatments, without losing revenue. Their increases in cash income would not always exceed the losses in gainful employment suffered by the farmworkers. For the majority of small farmers in the region - those who raise corn with family labor as the main resource - the new treatments do not appear to offer any economic advantages. The treatments are expensive, they offer little promise for raising yields, and their labor-saving effects do not fall squarely in the peak labor periods. It is suggested, therefore, that recommendation of the new treatments should be subject to the farmers' financial conditions and to their actual objectives in growing corn. The use of soil samples and research in the control of pasture weeds are also suggested for further research by the IPPC. Finally, it is suggested that assistance in the development of extra-local banana markets for small farmers might be of great value. Title: The agronomic, economic and social effects of the availability of new weed control treatments to small corn farmers in the North Atlantic Zone of Costa Rica Author: McCarty, Thomas Vere The North Atlantic zone of Costa Rica is an alluvial plain, whose fairly good soils and warm, extremely wet climate generate serious weed problems in cultivated crops and pastureland. Basic foods - corn, beans, rice and yuca - are important small farm crops. New land is still being opened for small farming, encouraged by a government-sponsored homesteading program. Research was initiated in 1976 by the International Plant Protection Center, in cooperation with CATIE, to determine whether the weed control practices currently used by small farmers could be improved. Agronomic results indicate that tilling the soil gives no advantage over the farmers present no-tillage methods. Pre-plant treatments with the herbicides glyphosate and paraquat have been shown to save labor in corn crops. There is little evidence that the new treatments raise corn yields. A survey of small farmers was conducted in the region in 1977 and 1978. A random sample of 21 farmers were selected for interviews. The information included a general description of each farm family and the complete farm operation and detailed descriptions of cultural practices in corn and beans crop, with special emphasis on weed control. Social and economic information was also obtained. Small farms in the sample are in various stages of development. The first step is usually to brush out the native timberland and fence off areas for a few cattle to graze. Then parcels are cleared for annual crops, especially corn, which is the most dependable cash crop. The farmer rotates parcels for annual crops, weedy fallow and pasture. He constantly attempts to build up his beef herd. Development of perennial plots is limited by the quantities demanded for home and local use. Nearly half the labor, and half the cash resources, expended in corn production are for weed control. The farmers typically cut the weeds with machete and leave the vegetation as mulch before planting, weed the crop with machete or with very light applications of 2,4-D, and cut the weeds once more with machete before doubling the ears and harvesting. Some temporary local shortages of labor occur in the peak periods, when harvesting for one season overlaps with soil preparation and planting for the next, although general underemployment prevails in the long slack periods. Weed conditions influence greatly the quantities of labor used for weed control. Rottboellia exaltata is the most noxious weed in corn cropping. The quantitative information from the survey was tabulated in partial budgets or detailed accounting sheets of variable costs and revenues, for corn parcels on each sample farm. Analysis of variance and regression models were used to test hypothetical relationships among the variables. These results were then compared with estimated capabilities and costs of the experimental weed control treatments for the corn crop on each sample farm. Reported wage rates and calculated returns to family labor were used to estimate the values of family labor. It was found that a minority of the small corn farmers - those who currently use relatively high quantities of cash resources - might be able to reduce costs with the new treatments, without losing revenue. Their increases in cash income would not always exceed the losses in gainful employment suffered by the farmworkers. For the majority of small farmers in the region - those who raise corn with family labor as the main resource - the new treatments do not appear to offer any economic advantages. The treatments are expensive, they offer little promise for raising yields, and their labor-saving effects do not fall squarely in the peak labor periods. It is suggested, therefore, that recommendation of the new treatments should be subject to the farmers' financial conditions and to their actual objectives in growing corn. The use of soil samples and research in the control of pasture weeds are also suggested for further research by the IPPC. Finally, it is suggested that assistance in the development of extra-local banana markets for small farmers might be of great value. Close

• 28. [Article] Effect of seed protein content on plant growth of barley and wheat

  The purpose of this study was to evaluate the effect of seed protein content on plant growth of barley (Hordeum vulgare L. ) and wheat (Triticum aestivum L. ). The effects of nitrogen application on chemical ...

  Citation × Citation Citation Abstract Copy Title: Effect of seed protein content on plant growth of barley and wheat Author: Lopez, Arturo The purpose of this study was to evaluate the effect of seed protein content on plant growth of barley (Hordeum vulgare L. ) and wheat (Triticum aestivum L. ). The effects of nitrogen application on chemical and morphological characteristics of the seed were also studied. Seeds of 'Casbon' winter barley and 'Nugaines' winter wheat with different protein content were obtained by field applications of various amounts of nitrogen at seeding time (fall) and tillering time (spring). The increase in protein content from high nitrogen rates was accompanied by a decrease in seed size and yield. The protein increase occurred primarily in the endosperm. Neither protein content nor size of the embryo was affected by rates of nitrogen application. The effect of seed protein content on plant growth was evaluated in terms of inhibition and respiration, speed of germination and subsequent seedling growth, root and shoot elongation at 15, 20 and 25C, and dry matter production when grown in low and high nitrogen soils in the green house. A positive relationship was found between seed protein content and plant performance. The rates of water absorption and oxygen consumption of germinating barley and wheat seed increased as a result of high protein content. High protein seed had a faster speed of germination and developed into larger seedlings with a higher dry matter content when grown in nitrogen-deficient soil. In nitrogen-enriched soil, seed protein content had little effect on seedling growth. The beneficial effects of seed protein content are more clearly expressed under stress conditions and are more evident when plant growth depends on the nutrients available from the seed. During initiation of germination, temperature influences the expression of the protein effect. After the seedling has formed and is capable of photosynthesis, the nitrogen availability in the soil influences the effect of seed protein content on plant growth. The relationship between seed protein content and plant growth can be an important factor in crop production because the increase in protein can be controlled by field application of nitrogen. However, since the high rates of nitrogen necessary to produce high seed protein levels are not consistent with the optimum nitrogen rates for yield, growers would probably be reluctant to apply such high rates unless some type of incentive were given them to do so. For seed production, it could still be important to strive for high protein levels in spite of some loss in yield if improved performance from high protein seeds proves to be of economic value. The results of this study indicate that producing and planting seeds rich in protein may be an effective method of achieving faster stand establishment of cereal crops. Additional research will determine the effects of high protein on yield. Title: Effect of seed protein content on plant growth of barley and wheat Author: Lopez, Arturo The purpose of this study was to evaluate the effect of seed protein content on plant growth of barley (Hordeum vulgare L. ) and wheat (Triticum aestivum L. ). The effects of nitrogen application on chemical and morphological characteristics of the seed were also studied. Seeds of 'Casbon' winter barley and 'Nugaines' winter wheat with different protein content were obtained by field applications of various amounts of nitrogen at seeding time (fall) and tillering time (spring). The increase in protein content from high nitrogen rates was accompanied by a decrease in seed size and yield. The protein increase occurred primarily in the endosperm. Neither protein content nor size of the embryo was affected by rates of nitrogen application. The effect of seed protein content on plant growth was evaluated in terms of inhibition and respiration, speed of germination and subsequent seedling growth, root and shoot elongation at 15, 20 and 25C, and dry matter production when grown in low and high nitrogen soils in the green house. A positive relationship was found between seed protein content and plant performance. The rates of water absorption and oxygen consumption of germinating barley and wheat seed increased as a result of high protein content. High protein seed had a faster speed of germination and developed into larger seedlings with a higher dry matter content when grown in nitrogen-deficient soil. In nitrogen-enriched soil, seed protein content had little effect on seedling growth. The beneficial effects of seed protein content are more clearly expressed under stress conditions and are more evident when plant growth depends on the nutrients available from the seed. During initiation of germination, temperature influences the expression of the protein effect. After the seedling has formed and is capable of photosynthesis, the nitrogen availability in the soil influences the effect of seed protein content on plant growth. The relationship between seed protein content and plant growth can be an important factor in crop production because the increase in protein can be controlled by field application of nitrogen. However, since the high rates of nitrogen necessary to produce high seed protein levels are not consistent with the optimum nitrogen rates for yield, growers would probably be reluctant to apply such high rates unless some type of incentive were given them to do so. For seed production, it could still be important to strive for high protein levels in spite of some loss in yield if improved performance from high protein seeds proves to be of economic value. The results of this study indicate that producing and planting seeds rich in protein may be an effective method of achieving faster stand establishment of cereal crops. Additional research will determine the effects of high protein on yield. Close

• 29. [Article] Biodiesel in Oregon: an agricultural perspective

  Biodiesel is a renewable, non-toxic, and biodegradable diesel fuel made from agricultural feedstocks. With a vibrant agricultural industry, Oregon is positioned to play an important role in the future ...

  Citation × Citation Citation Abstract Copy Title: Biodiesel in Oregon: an agricultural perspective Author: Lahmann, Emily Loren Biodiesel is a renewable, non-toxic, and biodegradable diesel fuel made from agricultural feedstocks. With a vibrant agricultural industry, Oregon is positioned to play an important role in the future of this energy source. Limiting factors to widespread biodiesel production include low value of biodiesel feedstock crops, lack of infrastructure, lagging consumer demand, and high production costs. These factors are slowing the growth of the biodiesel industry in Oregon. This project identified opportunities and limitations for a partnership between agriculture and biodiesel in the Willamette Valley and the state of Oregon more broadly. In-depth interviews and a survey of farmer attitudes toward, familiarity with, and experience with biodiesel were conducted. Findings from this survey indicate that a majority of farmers are aware of the role agriculture can play in the future of biodiesel, agree that they have an opportunity to help reduce our nation’s dependence on foreign oil, believe that biodiesel will be an important national market for Oregon agricultural products in the next ten years, and are interested in the ability of biodiesel to provide a profitable crop. The opportunities are obvious; farmers are positively predisposed to biodiesel and wait for openings to become full participants in Oregon’s biodiesel future. Title: Biodiesel in Oregon: an agricultural perspective Author: Lahmann, Emily Loren Biodiesel is a renewable, non-toxic, and biodegradable diesel fuel made from agricultural feedstocks. With a vibrant agricultural industry, Oregon is positioned to play an important role in the future of this energy source. Limiting factors to widespread biodiesel production include low value of biodiesel feedstock crops, lack of infrastructure, lagging consumer demand, and high production costs. These factors are slowing the growth of the biodiesel industry in Oregon. This project identified opportunities and limitations for a partnership between agriculture and biodiesel in the Willamette Valley and the state of Oregon more broadly. In-depth interviews and a survey of farmer attitudes toward, familiarity with, and experience with biodiesel were conducted. Findings from this survey indicate that a majority of farmers are aware of the role agriculture can play in the future of biodiesel, agree that they have an opportunity to help reduce our nation’s dependence on foreign oil, believe that biodiesel will be an important national market for Oregon agricultural products in the next ten years, and are interested in the ability of biodiesel to provide a profitable crop. The opportunities are obvious; farmers are positively predisposed to biodiesel and wait for openings to become full participants in Oregon’s biodiesel future. Close

• 30. [Article] Quantifying the fertilizer value of algal meal : an evaluation of an integrated dairy-anaerobic digester-algae production facility

  Algae have shown great potential as a source for renewable fuels. However, current production schemes have not been able to prove a sustainable energy return on investment due in part to the high costs ...

  Citation × Citation Citation Abstract Copy Title: Quantifying the fertilizer value of algal meal : an evaluation of an integrated dairy-anaerobic digester-algae production facility Author: Andrews, Shannon B. Algae have shown great potential as a source for renewable fuels. However, current production schemes have not been able to prove a sustainable energy return on investment due in part to the high costs of nutrient addition and the energy required for drying the biomass. Integrated algae-dairy production systems have been posited as a potential solution for algal production barriers as well as a way to capture environmentally problematic nutrients excreted by animals in concentrated animal feeding operations. As the organic food industry grows, so will the need for organic nitrogen (N) fertilizers. Algal meal, the high protein co-product of algal biodiesel production, could help meet this need. This work has two objectives: 1) to quantify the fertilizer value of algal meal relative to an organic N fertilizer, feather meal, and a conventional standard, urea; 2) to show that utilizing the fertilizer value of algal meal at $800 Mg⁻¹ will allow an integrated dairy-anaerobic digester-algae production facility to be an economically viable manure management system. A laboratory incubation was carried out to characterize carbon (C) and N mineralization of two different algal meal products. The N mineralization rate, C respiration rate, and impact on pH and soluble salts were the same for feather meal and one of the algal meals. A field trial was conducted to assess the overall crop productivity of corn grown with algal meal fertilizer, feather meal, and urea. There was no significant difference in corn ear yield or ear N uptake among any of the algal meal treatment rates (101 kg N ha⁻¹, 146 kg N ha⁻¹, 190 kg N ha⁻¹) and the high rate of feather meal or urea (190 kg N ha⁻¹) application. These results indicate that algal meal is an effective N fertilizer that should be valued relative to feather meal on a price per unit of nutrient basis. Considering environmental benefits and current policy incentives, assigning a fertilizer value of algal meal of $800 Mg⁻¹ for a 7-3-1 product adds enough income to make an integrated dairy-anaerobic digester-algae system an economically viable, sustainable farm-energy production system. Title: Quantifying the fertilizer value of algal meal : an evaluation of an integrated dairy-anaerobic digester-algae production facility Author: Andrews, Shannon B. Algae have shown great potential as a source for renewable fuels. However, current production schemes have not been able to prove a sustainable energy return on investment due in part to the high costs of nutrient addition and the energy required for drying the biomass. Integrated algae-dairy production systems have been posited as a potential solution for algal production barriers as well as a way to capture environmentally problematic nutrients excreted by animals in concentrated animal feeding operations. As the organic food industry grows, so will the need for organic nitrogen (N) fertilizers. Algal meal, the high protein co-product of algal biodiesel production, could help meet this need. This work has two objectives: 1) to quantify the fertilizer value of algal meal relative to an organic N fertilizer, feather meal, and a conventional standard, urea; 2) to show that utilizing the fertilizer value of algal meal at $800 Mg⁻¹ will allow an integrated dairy-anaerobic digester-algae production facility to be an economically viable manure management system. A laboratory incubation was carried out to characterize carbon (C) and N mineralization of two different algal meal products. The N mineralization rate, C respiration rate, and impact on pH and soluble salts were the same for feather meal and one of the algal meals. A field trial was conducted to assess the overall crop productivity of corn grown with algal meal fertilizer, feather meal, and urea. There was no significant difference in corn ear yield or ear N uptake among any of the algal meal treatment rates (101 kg N ha⁻¹, 146 kg N ha⁻¹, 190 kg N ha⁻¹) and the high rate of feather meal or urea (190 kg N ha⁻¹) application. These results indicate that algal meal is an effective N fertilizer that should be valued relative to feather meal on a price per unit of nutrient basis. Considering environmental benefits and current policy incentives, assigning a fertilizer value of algal meal of $800 Mg⁻¹ for a 7-3-1 product adds enough income to make an integrated dairy-anaerobic digester-algae system an economically viable, sustainable farm-energy production system. Close

• 31. [Article] Broadening the horizons of inland fish-farming in the African economy

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Broadening the horizons of inland fish-farming in the African economy Author: Tazoacha, Francis Research Paper Title: Broadening the horizons of inland fish-farming in the African economy Author: Tazoacha, Francis Research Paper Close

• 32. [Article] The influence of air and soil temperatures on the growth and development of Easter lily, Lilium longiflorum, during different growth phases

  Greenhouse-grown, September-harvested Lilium longiflorum cv. 'Nellie white' bulbs were used to determine temperature requirements during 5 pre-bloom and 1 post-bloom phases of development each of 1 month's ...

  Citation × Citation Citation Abstract Copy Title: The influence of air and soil temperatures on the growth and development of Easter lily, Lilium longiflorum, during different growth phases Author: Wang, Yin-Tung Greenhouse-grown, September-harvested Lilium longiflorum cv. 'Nellie white' bulbs were used to determine temperature requirements during 5 pre-bloom and 1 post-bloom phases of development each of 1 month's duration. Plantes were subjected to 3 air temperatures(24°day/ 18°C night, 18°/13° and 13°/10°) in combination with soil temperatures at 30°, 24°, and equal to or lower than ambient air temperature during each growth phase and evaluated by growth analysis at the termination of each phase. This study has substantiated that top growth needs high air temperature and daughter scale initiation and filling require high soil temperature. An air and soil temperature of 24°C was required for rapid flowering, leaf unfolding and stem elongation but at the expense of reserves in mother scales. Air temperature approaching 18°/13° during the month prior to anthesis favored maintenance of mother scales. Growth of daughter scales during the pre-bloom period was directly related to soil temperature rather than air temperature with 30° soil temperature being no better than 24°. Soil temperature had no effect on flower bud expansion after buds-visible stage, air temperature being the determining factor thereafter. Growth of the flower bud, leaf unfolding rate or stem elongation were of equal value in monitoring crop growth rate and status. Soil temperatures approaching 24°C. favored scale primordia initiation, regardless of air temperature. Daughter meristem diameter, as well as the rate of scale primordia initiation decreased progressively from daughter bulb appearance toward anthesis of the mother axis. High soil temperatures also reduced daughter bulb apex diameter during early growth phases. Since prevailing air and soil temperatures in the commercial lily growing sites are below those required for maximum growth and development of above- and below-ground organs during the pre-bloom period, it is concluded that air temperatures alone are adequate in monitoring field crop status and predicting ultimate yield potential during this period. Title: The influence of air and soil temperatures on the growth and development of Easter lily, Lilium longiflorum, during different growth phases Author: Wang, Yin-Tung Greenhouse-grown, September-harvested Lilium longiflorum cv. 'Nellie white' bulbs were used to determine temperature requirements during 5 pre-bloom and 1 post-bloom phases of development each of 1 month's duration. Plantes were subjected to 3 air temperatures(24°day/ 18°C night, 18°/13° and 13°/10°) in combination with soil temperatures at 30°, 24°, and equal to or lower than ambient air temperature during each growth phase and evaluated by growth analysis at the termination of each phase. This study has substantiated that top growth needs high air temperature and daughter scale initiation and filling require high soil temperature. An air and soil temperature of 24°C was required for rapid flowering, leaf unfolding and stem elongation but at the expense of reserves in mother scales. Air temperature approaching 18°/13° during the month prior to anthesis favored maintenance of mother scales. Growth of daughter scales during the pre-bloom period was directly related to soil temperature rather than air temperature with 30° soil temperature being no better than 24°. Soil temperature had no effect on flower bud expansion after buds-visible stage, air temperature being the determining factor thereafter. Growth of the flower bud, leaf unfolding rate or stem elongation were of equal value in monitoring crop growth rate and status. Soil temperatures approaching 24°C. favored scale primordia initiation, regardless of air temperature. Daughter meristem diameter, as well as the rate of scale primordia initiation decreased progressively from daughter bulb appearance toward anthesis of the mother axis. High soil temperatures also reduced daughter bulb apex diameter during early growth phases. Since prevailing air and soil temperatures in the commercial lily growing sites are below those required for maximum growth and development of above- and below-ground organs during the pre-bloom period, it is concluded that air temperatures alone are adequate in monitoring field crop status and predicting ultimate yield potential during this period. Close

• 33. [Article] Effect of cereal companion crops on the establishment of red fescue (Festuca rubra L.) for seed production

  Some perennial grass seed crops such as red fescue (Festuca rubra L.) do not produce a profitable seed crop during the first growing season. The present establishment method in Oregon for red fescue seed crops ...

  Citation × Citation Citation Abstract Copy Title: Effect of cereal companion crops on the establishment of red fescue (Festuca rubra L.) for seed production Author: Chastain, Thomas G. Some perennial grass seed crops such as red fescue (Festuca rubra L.) do not produce a profitable seed crop during the first growing season. The present establishment method in Oregon for red fescue seed crops generally entails spring planting which does not satisfy vernalization requirements for seed production in the year of planting. This establishment procedure relies on the amortization of establishment costs over the seed producing life of the stand. In Europe, perennial grass seed crops are often established with annual companion crops such as winter rape, flax, peas and cereals. Companion crops provide income in the year of establishment, thereby increasing the profitability of the seed production venture over the life of the stand. However, the companion crop competes with the grass seed crop for light, soil moisture and nutrients which often causes unsatisfactory establishment. The primary objective of this study was to determine the feasibility of establishing red fescue with cereal companion crops in Oregon's Willamette Valley. The second objective was to examine the influence of cereal companion crops, cultivars and row spacings on the growth and environment of red fescue. This was investigated to identify companion cropping methods that would be the least competitive with the establishing seed crop. The third objective was to evaluate the effect of companion cropping on subsequent red fescue seed production and income relationships over a two-year period. Two experiments were initiated in October 1982 and October 1983 at the Oregon State University Hyslop Crop Science Field Laboratory. 'Pennlawn' red fescue was established with two winter wheat cultivars, 'Hill 81' and 'Yamhill1, and two winter barley cultivars, 'Hesk' and 'Scio', as companion crops. Cereal companion crops were drilled in 15-, 30-, 45-, and 60-cm row spacings, perpendicular to red fescue rows. Red fescue was also established without a companion crop as a control. Companion crop tiller height, tillers m⁻² and leaf area tiller⁻¹ were measured to determine their influence on red fescue growth and development during establishment. The effect of cereal companion crops on red fescue environment was investigated by measuring photosynthetic photon flux density (PPFD) incident on red fescue plants and by determining soil moisture levels. Red fescue tiller height, leaf area, dry matter production, and tillers m⁻² were examined to evaluate the effect of companion crops on red fescue growth. Companion crop grain yields were obtained to calculate additional revenues from establishment with companion crops. First-year red fescue seed yield and yield components were measured to determine the seed production capability of red fescue established with cereal companion crops. Finally, a partial budgeting technique was employed to evaluate the economic feasibility of companion cropping in Oregon. Cereal companion crops markedly reduced PPFD incident on red fescue plants. This greatly decreased red fescue tiller m⁻², dry matter m⁻², individual tiller weight, and increased the height of tillers. Leaf area tiller⁻¹ was generally unaffected by companion crops. Increasing companion crop row spacing resulted in more red fescue tillers m⁻², dry matter m⁻² and reduced etiolation of tillers because of higher PPFD availability. Soil moisture content was not decreased by establishment with cereal companion crops. Although companion crops adversely affected red fescue growth during the establishment year, first-year seed yield was not significantly reduced. Red fescue seed yields ranged from 490 kg ha⁻¹ when planted with Hill 81 wheat to 654 kg ha⁻¹ with Scio barley. The seed yield of red fescue planted without a companion crop was 589 kg ha⁻¹. Establishment with Yamhill wheat in 15-cm rows increased net income over a two-year period by $416 ha⁻¹ over monocultural red fescue. Establishment with Hesk barley proved to be the least successful in terms of income. Establishment with companion crops was shown to be most profitable when cereal market prices were high and red fescue prices low. The results of this research clearly indicate the potential for increased profits by establishment of red fescue seed crops with cereal companion crops. Title: Effect of cereal companion crops on the establishment of red fescue (Festuca rubra L.) for seed production Author: Chastain, Thomas G. Some perennial grass seed crops such as red fescue (Festuca rubra L.) do not produce a profitable seed crop during the first growing season. The present establishment method in Oregon for red fescue seed crops generally entails spring planting which does not satisfy vernalization requirements for seed production in the year of planting. This establishment procedure relies on the amortization of establishment costs over the seed producing life of the stand. In Europe, perennial grass seed crops are often established with annual companion crops such as winter rape, flax, peas and cereals. Companion crops provide income in the year of establishment, thereby increasing the profitability of the seed production venture over the life of the stand. However, the companion crop competes with the grass seed crop for light, soil moisture and nutrients which often causes unsatisfactory establishment. The primary objective of this study was to determine the feasibility of establishing red fescue with cereal companion crops in Oregon's Willamette Valley. The second objective was to examine the influence of cereal companion crops, cultivars and row spacings on the growth and environment of red fescue. This was investigated to identify companion cropping methods that would be the least competitive with the establishing seed crop. The third objective was to evaluate the effect of companion cropping on subsequent red fescue seed production and income relationships over a two-year period. Two experiments were initiated in October 1982 and October 1983 at the Oregon State University Hyslop Crop Science Field Laboratory. 'Pennlawn' red fescue was established with two winter wheat cultivars, 'Hill 81' and 'Yamhill1, and two winter barley cultivars, 'Hesk' and 'Scio', as companion crops. Cereal companion crops were drilled in 15-, 30-, 45-, and 60-cm row spacings, perpendicular to red fescue rows. Red fescue was also established without a companion crop as a control. Companion crop tiller height, tillers m⁻² and leaf area tiller⁻¹ were measured to determine their influence on red fescue growth and development during establishment. The effect of cereal companion crops on red fescue environment was investigated by measuring photosynthetic photon flux density (PPFD) incident on red fescue plants and by determining soil moisture levels. Red fescue tiller height, leaf area, dry matter production, and tillers m⁻² were examined to evaluate the effect of companion crops on red fescue growth. Companion crop grain yields were obtained to calculate additional revenues from establishment with companion crops. First-year red fescue seed yield and yield components were measured to determine the seed production capability of red fescue established with cereal companion crops. Finally, a partial budgeting technique was employed to evaluate the economic feasibility of companion cropping in Oregon. Cereal companion crops markedly reduced PPFD incident on red fescue plants. This greatly decreased red fescue tiller m⁻², dry matter m⁻², individual tiller weight, and increased the height of tillers. Leaf area tiller⁻¹ was generally unaffected by companion crops. Increasing companion crop row spacing resulted in more red fescue tillers m⁻², dry matter m⁻² and reduced etiolation of tillers because of higher PPFD availability. Soil moisture content was not decreased by establishment with cereal companion crops. Although companion crops adversely affected red fescue growth during the establishment year, first-year seed yield was not significantly reduced. Red fescue seed yields ranged from 490 kg ha⁻¹ when planted with Hill 81 wheat to 654 kg ha⁻¹ with Scio barley. The seed yield of red fescue planted without a companion crop was 589 kg ha⁻¹. Establishment with Yamhill wheat in 15-cm rows increased net income over a two-year period by $416 ha⁻¹ over monocultural red fescue. Establishment with Hesk barley proved to be the least successful in terms of income. Establishment with companion crops was shown to be most profitable when cereal market prices were high and red fescue prices low. The results of this research clearly indicate the potential for increased profits by establishment of red fescue seed crops with cereal companion crops. Close

• 34. [Article] Biological considerations for a new approach to regulating genetically modified crops in the United States

  The debate over GM crops is one of the most controversial issues of recent decades. The debate has many dimensions, including environmental impacts, benefits and risks to human health, intellectual property ...

  Citation × Citation Citation Abstract Copy Title: Biological considerations for a new approach to regulating genetically modified crops in the United States Author: McDonough, Ashley The debate over GM crops is one of the most controversial issues of recent decades. The debate has many dimensions, including environmental impacts, benefits and risks to human health, intellectual property rights, adequacy of biosafety regulations, and fundamental ethical acceptability. The potential benefits of GM crops are numerous, including improved nutritional value, decreased production costs, resistance to pests, and reduced pesticide use. However, there are also substantial and complex health, environmental, and social risks, including effects on gene flow and biodiversity, creation of new toxins or allergens in food, consolidation of seed companies, and restricted access to genetic information and methods. Current US regulations are imposed only on crops produced through recombinant DNA methods, though all of these risks apply to crops modified through conventional biotechnologies as well. I argue that this current regulatory system impedes progress by presenting large obstacles to even low risk GM crops with medical and economic benefits. I suggest that a better approach would be a tiered system that takes into account the specific biological properties of the modified traits, the biology of the crops in which they are produced, and the environments in which they are grown. Title: Biological considerations for a new approach to regulating genetically modified crops in the United States Author: McDonough, Ashley The debate over GM crops is one of the most controversial issues of recent decades. The debate has many dimensions, including environmental impacts, benefits and risks to human health, intellectual property rights, adequacy of biosafety regulations, and fundamental ethical acceptability. The potential benefits of GM crops are numerous, including improved nutritional value, decreased production costs, resistance to pests, and reduced pesticide use. However, there are also substantial and complex health, environmental, and social risks, including effects on gene flow and biodiversity, creation of new toxins or allergens in food, consolidation of seed companies, and restricted access to genetic information and methods. Current US regulations are imposed only on crops produced through recombinant DNA methods, though all of these risks apply to crops modified through conventional biotechnologies as well. I argue that this current regulatory system impedes progress by presenting large obstacles to even low risk GM crops with medical and economic benefits. I suggest that a better approach would be a tiered system that takes into account the specific biological properties of the modified traits, the biology of the crops in which they are produced, and the environments in which they are grown. Close

• 35. [Article] The effect of soil acidity and lime placement on root growth and yield of winter wheat and alfalfa

  The application of lime to an acid Nekia soil significantly increased the yield of winter wheat and alfalfa in a field experiment. Crop yields maximized when the lime was partially mixed into the surface four ...

  Citation × Citation Citation Abstract Copy Title: The effect of soil acidity and lime placement on root growth and yield of winter wheat and alfalfa Author: Kauffman, Marvin Dean The application of lime to an acid Nekia soil significantly increased the yield of winter wheat and alfalfa in a field experiment. Crop yields maximized when the lime was partially mixed into the surface four inches of the soil. Thorough mixing of the lime into the surface six inches of soil did not increase crop yields over partial mixing of lime, and on some plots the yields were reduced by the more thorough mixing treatment. The reduction in yield on the thoroughly mixed plots occurred with the lower rates of lime application. Deterioration of soil structure due to rototilling was also a factor in the reduction of yield in the plots where the lime was thoroughly mixed. The yields of wheat decreased over a three-year period following the application of one ton of lime per acre. It was felt that part of this decrease in yield was caused by a more thorough mixing of the lime into the soil with annual seedbed preparation on the partially mixed plots, and by a decrease of Ca and increase of Al in the soil solution as the quantity of free lime in the soil decreased. The importance of the soil solution pH and Al and Ca concentrations in the soil solution is also demonstrated by the fact that the R 2 values for the relationship between the soil test pH and wheat yields, were highest for the 1 N KC1 pH values the first two years, and highest for the water pH value the third year. Third-year wheat yields were also decreased by an infestation of the root fungus, Ophiobolus Graninus, with the adverse effect on the yield decreasing as the lime rates increased. High levels of soil acidity adversely affected the survival of the alfalfa seedlings and the rhizobia which inoculate the alfalfa. The concentration of nitrogen in the plants and the quantity of nitrogen harvested in the plants, increased as the rate of lime applied increased. The wheat and alfalfa roots which grew in the unlimed soil exhibited Al-toxicity symptoms. The Al-toxic roots were thicker than the healthy roots, and there was very little lateral root development on the Al-affected roots. The application of the intermediate and high rates of lime to the acid Nekia soil eliminated the Al-toxicity symptoms and promoted the growth of fine fibrous root systems. The distribution of the alfalfa roots in the samples taken from the field experiment, corresponded with the distribution of the lime in the soil. The field experimental data showed that the yields of wheat and alfalfa were closely correlated to the weight of the root samples. Growth chamber experiments using winter wheat as an indicator crop and acid Nekia and Dayton soils were also conducted. Maximum yields of dry matter were harvested when 30 per cent of the total soil volume was limed, and the dry matter yield decreased as the low rate of lime was mixed into larger volumes of soil. The wheat roots grew in the limed portion of soil, whereas root growth was restricted in the unlimed soil. Plant analysis data showed that the concentrations of plant nutrients were similar for all lime treatments. Plant water potential data indicated that water stress induced by Al-toxicity of wheat roots contributed to the lower yields of wheat grown in soil receiving zero and one ton of lime per acre. Title: The effect of soil acidity and lime placement on root growth and yield of winter wheat and alfalfa Author: Kauffman, Marvin Dean The application of lime to an acid Nekia soil significantly increased the yield of winter wheat and alfalfa in a field experiment. Crop yields maximized when the lime was partially mixed into the surface four inches of the soil. Thorough mixing of the lime into the surface six inches of soil did not increase crop yields over partial mixing of lime, and on some plots the yields were reduced by the more thorough mixing treatment. The reduction in yield on the thoroughly mixed plots occurred with the lower rates of lime application. Deterioration of soil structure due to rototilling was also a factor in the reduction of yield in the plots where the lime was thoroughly mixed. The yields of wheat decreased over a three-year period following the application of one ton of lime per acre. It was felt that part of this decrease in yield was caused by a more thorough mixing of the lime into the soil with annual seedbed preparation on the partially mixed plots, and by a decrease of Ca and increase of Al in the soil solution as the quantity of free lime in the soil decreased. The importance of the soil solution pH and Al and Ca concentrations in the soil solution is also demonstrated by the fact that the R 2 values for the relationship between the soil test pH and wheat yields, were highest for the 1 N KC1 pH values the first two years, and highest for the water pH value the third year. Third-year wheat yields were also decreased by an infestation of the root fungus, Ophiobolus Graninus, with the adverse effect on the yield decreasing as the lime rates increased. High levels of soil acidity adversely affected the survival of the alfalfa seedlings and the rhizobia which inoculate the alfalfa. The concentration of nitrogen in the plants and the quantity of nitrogen harvested in the plants, increased as the rate of lime applied increased. The wheat and alfalfa roots which grew in the unlimed soil exhibited Al-toxicity symptoms. The Al-toxic roots were thicker than the healthy roots, and there was very little lateral root development on the Al-affected roots. The application of the intermediate and high rates of lime to the acid Nekia soil eliminated the Al-toxicity symptoms and promoted the growth of fine fibrous root systems. The distribution of the alfalfa roots in the samples taken from the field experiment, corresponded with the distribution of the lime in the soil. The field experimental data showed that the yields of wheat and alfalfa were closely correlated to the weight of the root samples. Growth chamber experiments using winter wheat as an indicator crop and acid Nekia and Dayton soils were also conducted. Maximum yields of dry matter were harvested when 30 per cent of the total soil volume was limed, and the dry matter yield decreased as the low rate of lime was mixed into larger volumes of soil. The wheat roots grew in the limed portion of soil, whereas root growth was restricted in the unlimed soil. Plant analysis data showed that the concentrations of plant nutrients were similar for all lime treatments. Plant water potential data indicated that water stress induced by Al-toxicity of wheat roots contributed to the lower yields of wheat grown in soil receiving zero and one ton of lime per acre. Close

• 36. [Article] Chilling as a factor in crop location with particular reference to deciduous orchards in California

  Several empirical formulas that may be used to estimate available chilling are presented in this study. Many climatic parameters were considered in the derivation of these formulas. One equation employing ...

  Citation × Citation Citation Abstract Copy Title: Chilling as a factor in crop location with particular reference to deciduous orchards in California Author: Aron, Robert Henry Several empirical formulas that may be used to estimate available chilling are presented in this study. Many climatic parameters were considered in the derivation of these formulas. One equation employing only maximum and minimum temperatures had a coefficients of correlation (R) and R² values of .978 and .957, respectively. This equation was used in estimating the availability of chilling at 273 stations throughout California. Using these estimates and considering such factors as altitude and marine influences, the availability of chilling throughout California was mapped. Factors that influence the effectiveness of the chilling received such as low and high temperatures, high light intensity, shade, fog, cloud cover, topography and wind were analyzed. Which temperatures are most effective in satisfying the plant's chilling requirement, the amount required by different varieties, the effects and consequences of inadequate chilling, and treatments which may ameliorate the effects of inadequate chilling were considered. Hormonal and physical and anatomical plant response changes occurring during rest were discussed. Title: Chilling as a factor in crop location with particular reference to deciduous orchards in California Author: Aron, Robert Henry Several empirical formulas that may be used to estimate available chilling are presented in this study. Many climatic parameters were considered in the derivation of these formulas. One equation employing only maximum and minimum temperatures had a coefficients of correlation (R) and R² values of .978 and .957, respectively. This equation was used in estimating the availability of chilling at 273 stations throughout California. Using these estimates and considering such factors as altitude and marine influences, the availability of chilling throughout California was mapped. Factors that influence the effectiveness of the chilling received such as low and high temperatures, high light intensity, shade, fog, cloud cover, topography and wind were analyzed. Which temperatures are most effective in satisfying the plant's chilling requirement, the amount required by different varieties, the effects and consequences of inadequate chilling, and treatments which may ameliorate the effects of inadequate chilling were considered. Hormonal and physical and anatomical plant response changes occurring during rest were discussed. Close

• 37. [Article] Foliar interception and uptake of ³⁶Cl by crops

  Greenhouse studies were conducted to determine interception, absorption, and translocation values for foliar applied ³⁶Cl. Foliar interception and uptake of contaminated irrigation water by crops is a ...

  Citation × Citation Citation Abstract Copy Title: Foliar interception and uptake of ³⁶Cl by crops Author: Bytwerk, David Paul Greenhouse studies were conducted to determine interception, absorption, and translocation values for foliar applied ³⁶Cl. Foliar interception and uptake of contaminated irrigation water by crops is a major pathway for the transport of radionuclides to human beings in scenarios relevant to the waste disposal community. Performance assessments of many repositories that predict doses to people from long- term geological disposal of radioactive waste are equipped to consider foliar interception and uptake by crops on an element and crop specific basis in their predictions, but crop and element specific data does not exist in the literature to justify the choice of parameter values in these models. ³⁶Cl is among the isotopes for which there is a lack of data and has recently been predicted to be among the largest contributors to dose at the time of peak dose from many repositories. Reported here are ³⁶Cl foliar interception, absorption, and translocation parameters for three crops: a root vegetable -radishes, a fruit - beans, and a grain - wheat. Title: Foliar interception and uptake of ³⁶Cl by crops Author: Bytwerk, David Paul Greenhouse studies were conducted to determine interception, absorption, and translocation values for foliar applied ³⁶Cl. Foliar interception and uptake of contaminated irrigation water by crops is a major pathway for the transport of radionuclides to human beings in scenarios relevant to the waste disposal community. Performance assessments of many repositories that predict doses to people from long- term geological disposal of radioactive waste are equipped to consider foliar interception and uptake by crops on an element and crop specific basis in their predictions, but crop and element specific data does not exist in the literature to justify the choice of parameter values in these models. ³⁶Cl is among the isotopes for which there is a lack of data and has recently been predicted to be among the largest contributors to dose at the time of peak dose from many repositories. Reported here are ³⁶Cl foliar interception, absorption, and translocation parameters for three crops: a root vegetable -radishes, a fruit - beans, and a grain - wheat. Close

• 38. [Article] Improving nitrogen management with cover crops in organic broccoli production

  Legume cover crops can serve as important sources of nitrogen (N) in sustainable agriculture and can be economically beneficial when fertilizer inputs are reduced without a yield reduction. Synchronizing ...

  Citation × Citation Citation Abstract Copy Title: Improving nitrogen management with cover crops in organic broccoli production Author: Garrett, Amy (Amy Michelle) Legume cover crops can serve as important sources of nitrogen (N) in sustainable agriculture and can be economically beneficial when fertilizer inputs are reduced without a yield reduction. Synchronizing N mineralization from organic materials with the needs of the subsequent crop is a challenge for organic growers. Predicting plant available nitrogen from cover crop residue enables N fertilizer inputs to be adjusted for optimum economic yield and reduced environmental risk. An experiment was conducted near Corvallis, OR in 2006 through 2008 to evaluate cover crop and N effects in organic broccoli production in western Oregon. The specific objectives of this experiment were to: 1) evaluate biomass production and N accumulation from selected cover crop treatments; 2) compare the effects of selected cover crops grown as sole crops and as mixtures on broccoli yield, yield components, and net economic benefit; 3) estimate the quantity of feather meal N replaced by cover crops 4) estimate plant available nitrogen from cover crop residue in an organic broccoli production system; 5) evaluate soil NO₃₋N and petiole NO₃₋N as predictors of broccoli yield; and 6) evaluate models derived from laboratory incubation of cover crop residue to predict apparent nitrogen recovery (ANR) from cover crop residue in the field. The cover crop treatments included common vetch (Vicia sativa), phacelia (Phacelia tanacetifolia), 'Monida' oats (Avena sativa L.), phacelia plus common vetch, and 'Monida' oats plus common vetch. A fallow treatment was used as the control. Prior to incorporation, cover crop samples were collected from each block and frozen for later use in laboratory aerobic incubations. After the cover crops were flail-mowed and incorporated, four N rates (0, 100, 200, and 300 kg N ha⁻¹) were randomized within each cover crop treatment in a split plot design. All cover crop treatments produced much less biomass and accumulated less N in 2008 than in 2007. Planting vetch with oats or phacelia increased biomass production and N accumulation compared to sole crops in 2007 but not in 2008. Common vetch as a sole crop or in a mixture increased broccoli yield with 0 and 100 kg N ha⁻¹ applied compared to fallow. Legume cover crop mixtures with 100 kg N ha⁻¹ produced similar net economic returns for organic compared to fallow treatments with 300 kg N ha⁻¹. Nitrogen fertilizer input can be reduced by at least 100 kg N ha⁻¹ if common vetch is in the mixture and produces more than 5000 kg ha⁻¹ of biomass (130-180 kg N ha⁻¹). Vetch as a sole crop produced higher levels of soil NO₃₋N than the fallow treatments up to 80 days after soil incorporation in 2007. Oats and phacelia as sole crops, however, reduced soil NO₃₋N compared to fallow for up to 68 days after incorporation. Vetch mixtures with oats or phacelia produced intermediate levels of soil NO₃₋N between vetch as a sole crop and the fallow. Treatment effects were similar in 2008, but differences were less due to reduced cover crop biomass compared to 2007. Broccoli petiole nitrate levels were not affected by cover crop treatment in 2007, and there was no correlation with yield. In 2008, the oat cover crop treatment reduced broccoli petiole nitrate levels compared to the fallow. Petiole nitrate levels were strongly correlated with broccoli yield, with highest yields associated with petiole NO₃₋ N greater than 10,000 ppm. In the aerobic incubations with cover crop mixtures, a quadratic model described the relationship of percent N in the mixture to the apparent nitrogen recovery (ANR) at both 4 and 10 weeks. The highest ANR (about 40 percent) was similar for both extraction days. Net mineralization occurred when the percent N of the cover crop mixture was 1.5-1.8 percent. There was a strong correlation in 2007 between the ANR predicted by the incubation-derived model and the ANR in the soil and in the aboveground broccoli biomass. The model over predicted the ANR in the field soil, however the model more accurately predicted ANR in the broccoli biomass. The incubation model correctly predicted negative ANR values for the oat and phacelia cover-crop treatments. In 2008, the laboratory-predicted ANR and the field soil ANR were correlated (r²=.45), and the laboratory model over predicted the field ANR. The incubation model gave a poor prediction of broccoli biomass ANR. Title: Improving nitrogen management with cover crops in organic broccoli production Author: Garrett, Amy (Amy Michelle) Legume cover crops can serve as important sources of nitrogen (N) in sustainable agriculture and can be economically beneficial when fertilizer inputs are reduced without a yield reduction. Synchronizing N mineralization from organic materials with the needs of the subsequent crop is a challenge for organic growers. Predicting plant available nitrogen from cover crop residue enables N fertilizer inputs to be adjusted for optimum economic yield and reduced environmental risk. An experiment was conducted near Corvallis, OR in 2006 through 2008 to evaluate cover crop and N effects in organic broccoli production in western Oregon. The specific objectives of this experiment were to: 1) evaluate biomass production and N accumulation from selected cover crop treatments; 2) compare the effects of selected cover crops grown as sole crops and as mixtures on broccoli yield, yield components, and net economic benefit; 3) estimate the quantity of feather meal N replaced by cover crops 4) estimate plant available nitrogen from cover crop residue in an organic broccoli production system; 5) evaluate soil NO₃₋N and petiole NO₃₋N as predictors of broccoli yield; and 6) evaluate models derived from laboratory incubation of cover crop residue to predict apparent nitrogen recovery (ANR) from cover crop residue in the field. The cover crop treatments included common vetch (Vicia sativa), phacelia (Phacelia tanacetifolia), 'Monida' oats (Avena sativa L.), phacelia plus common vetch, and 'Monida' oats plus common vetch. A fallow treatment was used as the control. Prior to incorporation, cover crop samples were collected from each block and frozen for later use in laboratory aerobic incubations. After the cover crops were flail-mowed and incorporated, four N rates (0, 100, 200, and 300 kg N ha⁻¹) were randomized within each cover crop treatment in a split plot design. All cover crop treatments produced much less biomass and accumulated less N in 2008 than in 2007. Planting vetch with oats or phacelia increased biomass production and N accumulation compared to sole crops in 2007 but not in 2008. Common vetch as a sole crop or in a mixture increased broccoli yield with 0 and 100 kg N ha⁻¹ applied compared to fallow. Legume cover crop mixtures with 100 kg N ha⁻¹ produced similar net economic returns for organic compared to fallow treatments with 300 kg N ha⁻¹. Nitrogen fertilizer input can be reduced by at least 100 kg N ha⁻¹ if common vetch is in the mixture and produces more than 5000 kg ha⁻¹ of biomass (130-180 kg N ha⁻¹). Vetch as a sole crop produced higher levels of soil NO₃₋N than the fallow treatments up to 80 days after soil incorporation in 2007. Oats and phacelia as sole crops, however, reduced soil NO₃₋N compared to fallow for up to 68 days after incorporation. Vetch mixtures with oats or phacelia produced intermediate levels of soil NO₃₋N between vetch as a sole crop and the fallow. Treatment effects were similar in 2008, but differences were less due to reduced cover crop biomass compared to 2007. Broccoli petiole nitrate levels were not affected by cover crop treatment in 2007, and there was no correlation with yield. In 2008, the oat cover crop treatment reduced broccoli petiole nitrate levels compared to the fallow. Petiole nitrate levels were strongly correlated with broccoli yield, with highest yields associated with petiole NO₃₋ N greater than 10,000 ppm. In the aerobic incubations with cover crop mixtures, a quadratic model described the relationship of percent N in the mixture to the apparent nitrogen recovery (ANR) at both 4 and 10 weeks. The highest ANR (about 40 percent) was similar for both extraction days. Net mineralization occurred when the percent N of the cover crop mixture was 1.5-1.8 percent. There was a strong correlation in 2007 between the ANR predicted by the incubation-derived model and the ANR in the soil and in the aboveground broccoli biomass. The model over predicted the ANR in the field soil, however the model more accurately predicted ANR in the broccoli biomass. The incubation model correctly predicted negative ANR values for the oat and phacelia cover-crop treatments. In 2008, the laboratory-predicted ANR and the field soil ANR were correlated (r²=.45), and the laboratory model over predicted the field ANR. The incubation model gave a poor prediction of broccoli biomass ANR. Close

• 39. [Article] A production function analysis of water resource productivity in Pacific Northwest agriculture

  The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This ...

  Citation × Citation Citation Abstract Copy Title: A production function analysis of water resource productivity in Pacific Northwest agriculture Author: Holloway, Milton L. The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This rivalry and the long run prospects for water shortages have increased the demand for research concerning the productivity of this resource in alternative uses. This demand exists because the distribution and use of water resources require investment which typically comes from both public and private sources. Private and public planning groups seek answers to questions regarding future water resource development alternatives. Agriculture has historically been a major user of water in the Pacific Northwest. A substantial portion of total investment in water resource development has also been, in agriculture. As a result water use planners and decision making bodies are necessarily interested in water use in agriculture. The success of water resource planning requires answers to questions regarding the value of the productivity of water in all its major uses, including various aspects of water use in agriculture. Different aspects of water use in agriculture which are important to decision makers include (1) the value productivity of various kinds or types of water resource investments, (2) the value productivity of water in various kinds of agricultural production in different geographical areas, and (3) the returns to private and public investment in agricultural water resources. This study was directed to providing answers to these questions. Pacific Northwest agriculture was studied from this viewpoint. Agricultural water resources were classified as irrigation, drainage, and water related Agricultural Conservation Program (ACP) practices. These are the major classifications of water resources in which investments are made in the Pacific Northwest. Production function analysis was selected as a method of investigation. Production functions were estimated for five areas or subregions in the Pacific Northwest. These areas are composed of counties with similar patterns of production. The Agricultural Census was the primary data surce, supplemented by related U.S. Department of Agriculture publications, and various state publications, Ordinary least-squares regression (OLS) techniques were employed to derive the initial estimates of the parameters of the production function models. Tests for detecting interdependence within the independent variable set of the models revealed a considerable degree of instability in the OLS parameter estimates. This condition makes the OLS solutions (and various derivations) particularly vulnerable to change from measurement error, poor model specification, and equation form. A prior information model was selected to explicitly include available prior knowledge in the estimation process. The model selected allows (1) tests of comparability of the two information sources (prior and sample), (2) over-all contribution of prior information to the new solution set, and (3) derivation of percentage contribution of the two information sources to individual parameter estimates. The results of the study indicate that no reliable estimates of value of production from drainage and ACP were possible from the sample information. Returns to irrigation were considered lower than expected in two of the farming areas and higher than expected in another. Estimated returns were high in the area which produces primarily field crops (about nine dollars per acre foot). The area has a small level of current irrigation development. Indications are that irrigation development is probably beyond the optimum level in the area where most large, projects have been developed in the past (less than four dollars per acre foot). Future development would be most profitable (assuming equal development cost) in the dryland field crop area. Estimated returns to other factor inputs indicate (1) low returns to labor in two areas, (2) generally high returns to current operating expenditures, and (3) low returns to machinery capital. Returns to cropland were about as expected in two areas (five to seven percent) but low in two other areas (about two percent). Indications are that labor mobility should be increased in the area and that future land development should be in the livestock-field crop and the field crop areas rather than the coastal area or the west-central valley areas (primarily the Willamette Valley). Title: A production function analysis of water resource productivity in Pacific Northwest agriculture Author: Holloway, Milton L. The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This rivalry and the long run prospects for water shortages have increased the demand for research concerning the productivity of this resource in alternative uses. This demand exists because the distribution and use of water resources require investment which typically comes from both public and private sources. Private and public planning groups seek answers to questions regarding future water resource development alternatives. Agriculture has historically been a major user of water in the Pacific Northwest. A substantial portion of total investment in water resource development has also been, in agriculture. As a result water use planners and decision making bodies are necessarily interested in water use in agriculture. The success of water resource planning requires answers to questions regarding the value of the productivity of water in all its major uses, including various aspects of water use in agriculture. Different aspects of water use in agriculture which are important to decision makers include (1) the value productivity of various kinds or types of water resource investments, (2) the value productivity of water in various kinds of agricultural production in different geographical areas, and (3) the returns to private and public investment in agricultural water resources. This study was directed to providing answers to these questions. Pacific Northwest agriculture was studied from this viewpoint. Agricultural water resources were classified as irrigation, drainage, and water related Agricultural Conservation Program (ACP) practices. These are the major classifications of water resources in which investments are made in the Pacific Northwest. Production function analysis was selected as a method of investigation. Production functions were estimated for five areas or subregions in the Pacific Northwest. These areas are composed of counties with similar patterns of production. The Agricultural Census was the primary data surce, supplemented by related U.S. Department of Agriculture publications, and various state publications, Ordinary least-squares regression (OLS) techniques were employed to derive the initial estimates of the parameters of the production function models. Tests for detecting interdependence within the independent variable set of the models revealed a considerable degree of instability in the OLS parameter estimates. This condition makes the OLS solutions (and various derivations) particularly vulnerable to change from measurement error, poor model specification, and equation form. A prior information model was selected to explicitly include available prior knowledge in the estimation process. The model selected allows (1) tests of comparability of the two information sources (prior and sample), (2) over-all contribution of prior information to the new solution set, and (3) derivation of percentage contribution of the two information sources to individual parameter estimates. The results of the study indicate that no reliable estimates of value of production from drainage and ACP were possible from the sample information. Returns to irrigation were considered lower than expected in two of the farming areas and higher than expected in another. Estimated returns were high in the area which produces primarily field crops (about nine dollars per acre foot). The area has a small level of current irrigation development. Indications are that irrigation development is probably beyond the optimum level in the area where most large, projects have been developed in the past (less than four dollars per acre foot). Future development would be most profitable (assuming equal development cost) in the dryland field crop area. Estimated returns to other factor inputs indicate (1) low returns to labor in two areas, (2) generally high returns to current operating expenditures, and (3) low returns to machinery capital. Returns to cropland were about as expected in two areas (five to seven percent) but low in two other areas (about two percent). Indications are that labor mobility should be increased in the area and that future land development should be in the livestock-field crop and the field crop areas rather than the coastal area or the west-central valley areas (primarily the Willamette Valley). Close

• 40. [Article] A production function analysis of water resource productivity in Pacific Northwest agriculture

  The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This ...

  Citation × Citation Citation Abstract Copy Title: A production function analysis of water resource productivity in Pacific Northwest agriculture Author: Holloway, Milton L. The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This rivalry and the long run prospects for water shortages have increased the demand for research concerning the productivity of this resource in alternative uses. This demand exists because the distribution and use of water resources require investment which typically comes from both public and private sources. Private and public planning groups seek answers to questions regarding future water resource development alternatives. Agriculture has historically been a major user of water in the Pacific Northwest. A substantial portion of total investment in water resource development has also been in agriculture. As a result water use planners and decision making bodies are necessarily interested in water use in agriculture. The success of water resource planning requires answers to questions regarding the value of the productivity of water in all its major uses, including various aspects of water use in agriculture. Different aspects of water use in agriculture which are important to decision makers include (1) the value productivity of various kinds or types of water resource investments, (2) the value productivity of water in various kinds of agricultural production in different geographical areas, and (3) the returns to private and public investment in agricultural water resources. This study was directed to providing answers to these questions. Pacific Northwest agriculture was studied from this viewpoint. Agricultural water resources were classified as irrigation, drainage, and water related Agricultural Conservation Program (ACP) practices. These are the major classifications of water resources in which investments are made in the Pacific Northwest. Production function analysis was selected as a method of investigation. Production functions were estimated for five areas or subregions in the Pacific Northwest. These areas are composed of counties with similar patterns of production. The Agricultural Census was the primary data source, supplemented by related. U. S. Department of Agriculture publications, and various state publications. Ordinary least-squares regression (OLS) techniques were employed to derive the initial estimates of the parameters of the production function models. Tests for detecting interdependence within the independent variable set of the models revealed a considerable degree of instability in the OLS parameter estimates. This condition makes the OLS solutions (and various derivations) particularly vulnerable to change from measurement error, poor model specification, and equation form. A prior information model was selected to explicitly include available prior knowledge in the estimation process. The model selected allows (1) tests of comparability of the two information sources (prior and sample), (2) over-all contribution of prior information to the new solution set, and (3) derivation of percentage contribution of the two information sources to individual parameter estimates. The results of the study indicate that no reliable estimates of value of production from drainage and ACP were possible from the sample information. Returns to irrigation were considered lower than expected in two of the farming areas and higher than expected in another. Estimated returns were high in the area which produces primarily field crops (about nine dollars per acre foot). The area has a small level of current irrigation development. Indications are that irrigation development is probably beyond the optimum level in the area where most large projects have been developed in the past (less than four dollars per acre foot). Future development would be most profitable (assuming equal development cost) in the dryland field crop area. Estimated returns to other factor inputs indicate (1) low returns to labor in two areas, (2) generally high returns to current operating expenditures, and (3) low returns to machinery capital. Returns to cropland were about as expected in two areas (five to seven percent) but low in two other areas (about two percent). Indications are that labor mobility should be increased in the area and that future land development should be in the livestock-field crop and the field crop areas rather than the coastal area or the west-central valley areas (primarily the Willamette Valley). Title: A production function analysis of water resource productivity in Pacific Northwest agriculture Author: Holloway, Milton L. The competition or rivalry for the use of water resources among economic sectors of the Pacific Northwest and among geographical regions of the western United States has intensified in recent years. This rivalry and the long run prospects for water shortages have increased the demand for research concerning the productivity of this resource in alternative uses. This demand exists because the distribution and use of water resources require investment which typically comes from both public and private sources. Private and public planning groups seek answers to questions regarding future water resource development alternatives. Agriculture has historically been a major user of water in the Pacific Northwest. A substantial portion of total investment in water resource development has also been in agriculture. As a result water use planners and decision making bodies are necessarily interested in water use in agriculture. The success of water resource planning requires answers to questions regarding the value of the productivity of water in all its major uses, including various aspects of water use in agriculture. Different aspects of water use in agriculture which are important to decision makers include (1) the value productivity of various kinds or types of water resource investments, (2) the value productivity of water in various kinds of agricultural production in different geographical areas, and (3) the returns to private and public investment in agricultural water resources. This study was directed to providing answers to these questions. Pacific Northwest agriculture was studied from this viewpoint. Agricultural water resources were classified as irrigation, drainage, and water related Agricultural Conservation Program (ACP) practices. These are the major classifications of water resources in which investments are made in the Pacific Northwest. Production function analysis was selected as a method of investigation. Production functions were estimated for five areas or subregions in the Pacific Northwest. These areas are composed of counties with similar patterns of production. The Agricultural Census was the primary data source, supplemented by related. U. S. Department of Agriculture publications, and various state publications. Ordinary least-squares regression (OLS) techniques were employed to derive the initial estimates of the parameters of the production function models. Tests for detecting interdependence within the independent variable set of the models revealed a considerable degree of instability in the OLS parameter estimates. This condition makes the OLS solutions (and various derivations) particularly vulnerable to change from measurement error, poor model specification, and equation form. A prior information model was selected to explicitly include available prior knowledge in the estimation process. The model selected allows (1) tests of comparability of the two information sources (prior and sample), (2) over-all contribution of prior information to the new solution set, and (3) derivation of percentage contribution of the two information sources to individual parameter estimates. The results of the study indicate that no reliable estimates of value of production from drainage and ACP were possible from the sample information. Returns to irrigation were considered lower than expected in two of the farming areas and higher than expected in another. Estimated returns were high in the area which produces primarily field crops (about nine dollars per acre foot). The area has a small level of current irrigation development. Indications are that irrigation development is probably beyond the optimum level in the area where most large projects have been developed in the past (less than four dollars per acre foot). Future development would be most profitable (assuming equal development cost) in the dryland field crop area. Estimated returns to other factor inputs indicate (1) low returns to labor in two areas, (2) generally high returns to current operating expenditures, and (3) low returns to machinery capital. Returns to cropland were about as expected in two areas (five to seven percent) but low in two other areas (about two percent). Indications are that labor mobility should be increased in the area and that future land development should be in the livestock-field crop and the field crop areas rather than the coastal area or the west-central valley areas (primarily the Willamette Valley). Close

• 41. [Article] Influence of different nitrogen and moisture levels on the expression of grain yield and protein content in selected wheat (Triticum aestivum, L. em Thell) and barley (Hordeum vulagre, L. em Lam.) cultivars

  This investigation was conducted to provide information regarding 1) the relationship between the nitrogen percentage in the vegetative tissue of wheat and barley at various growth stages with grain protein and ...

  Citation × Citation Citation Abstract Copy Title: Influence of different nitrogen and moisture levels on the expression of grain yield and protein content in selected wheat (Triticum aestivum, L. em Thell) and barley (Hordeum vulagre, L. em Lam.) cultivars Author: Gomez-Pando, Luz This investigation was conducted to provide information regarding 1) the relationship between the nitrogen percentage in the vegetative tissue of wheat and barley at various growth stages with grain protein and 2) to evaluate the possible association between grain yield and grain protein as influenced by different cultivars, nitrogen levels and available moisture. Five wheat and four barley cultivars were selected based on their diverse genetic backgrounds and potential differences for the 12 attributes measured. These experimental materials were grown at low and high rainfall sites and under two different nitrogen levels. In wheat a decrease in the percentage of nitrogen in the flag leaves was found as the plants developed. The highest values were observed at the boot stage. In contrast, the highest percentage of nitrogen in the flag leaves of barley was observed at anthesis. Wheat cultivars which had the greatest genetic potential for grain protein usually had the highest percentage of nitrogen in the flag leaves at the boot stage and the lowest percentage in the vegetative tissue at harvest. This was especially true under high rainfall conditions. A similar relationship was found for the barley cultivars. At both experimental sites higher grain yields were accompanied by negative associations with grain protein for wheat. However, for barley no association was found between these two traits at either site or fertility level. Higher grain protein values were found for both wheat and barley at the high rainfall site. Title: Influence of different nitrogen and moisture levels on the expression of grain yield and protein content in selected wheat (Triticum aestivum, L. em Thell) and barley (Hordeum vulagre, L. em Lam.) cultivars Author: Gomez-Pando, Luz This investigation was conducted to provide information regarding 1) the relationship between the nitrogen percentage in the vegetative tissue of wheat and barley at various growth stages with grain protein and 2) to evaluate the possible association between grain yield and grain protein as influenced by different cultivars, nitrogen levels and available moisture. Five wheat and four barley cultivars were selected based on their diverse genetic backgrounds and potential differences for the 12 attributes measured. These experimental materials were grown at low and high rainfall sites and under two different nitrogen levels. In wheat a decrease in the percentage of nitrogen in the flag leaves was found as the plants developed. The highest values were observed at the boot stage. In contrast, the highest percentage of nitrogen in the flag leaves of barley was observed at anthesis. Wheat cultivars which had the greatest genetic potential for grain protein usually had the highest percentage of nitrogen in the flag leaves at the boot stage and the lowest percentage in the vegetative tissue at harvest. This was especially true under high rainfall conditions. A similar relationship was found for the barley cultivars. At both experimental sites higher grain yields were accompanied by negative associations with grain protein for wheat. However, for barley no association was found between these two traits at either site or fertility level. Higher grain protein values were found for both wheat and barley at the high rainfall site. Close

• 42. [Article] Developing Winter Food Barley for the Pacific Northwest of the US

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Crop Science Society of America and can be found at: https://dl.sciencesoci...

  Citation × Citation Citation Abstract Copy Title: Developing Winter Food Barley for the Pacific Northwest of the US Author: Kongraksawech, Teepakorn, Meints, Brigid, Cuesta-Marcos, Alfonso, Hayes, Patrick M., Marshall, Juliet M., Fisk, Scott, Ross, Andrew S., Murphy, Kevin This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Crop Science Society of America and can be found at: https://dl.sciencesocieties.org/publications/cs Title: Developing Winter Food Barley for the Pacific Northwest of the US Author: Kongraksawech, Teepakorn, Meints, Brigid, Cuesta-Marcos, Alfonso, Hayes, Patrick M., Marshall, Juliet M., Fisk, Scott, Ross, Andrew S., Murphy, Kevin This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Crop Science Society of America and can be found at: https://dl.sciencesocieties.org/publications/cs Close

• 43. [Article] Yield and quality of cereals for winter silage production

  A field study was conducted in 1978 and 1979 at two locations near Corvallis, Oregon, to determine the silage yield and quality of 13 fallsown cereal varieties at two nitrogen fertilizer levels in the ...

  Citation × Citation Citation Abstract Copy Title: Yield and quality of cereals for winter silage production Author: Ben Ali, Mohamed Noureddine A field study was conducted in 1978 and 1979 at two locations near Corvallis, Oregon, to determine the silage yield and quality of 13 fallsown cereal varieties at two nitrogen fertilizer levels in the context of a corn-winter cemal double cropping production system. Data on the yield, crude protein (CP) content, acid and neutral detergent fiber (ADF and NDF) contents were collected on Adair, Casbon and FB 73130 barley (Hordeum vulgare L.) varieties, Amity, Cayuse and Grey winter oats (Avena Sativa L.), Abruzi and Kung rye (Secale cereale L.), S-72, Sel N-91 and VT 75-229 Triticale (Triticum X Secale) and Stephens and Yamhill wheat (Triticum Aestivum L.) varieties. The statistical analysis of the data gave the following results. Dry matter yields ranged on the average from a high of 8327 kg/ha to a low of 4631 ka/ha. Abruzi rye generally yielded the most dry matter. It was followed by Sel N-91 and VT 75-229 Triticales, Kung rye, S-72 Triticale and the wheat varieties. The barley and oats varieties were generally the lowest producers. Crude protein content was within the range of 6,5 to 10.1 percent of the dry matter. It was on the average highest for FB 73130 barley followed by Casbon barley, Stephens wheat, Adair barley, Yamhill wheat and the Triticale varieties. Acid detergent fiber ranged from 30.8 to 46.4 percent of dry matter. The oats varieties had the lowest ADF values, followed by Stephens and Yamhill wheats, FB 73130 and Adair barleys and VT 75-229 Triticale. The average neutral detergent fiber content for the 13 cereal varieties varied from a low of 50.3 to a high of 69.4 percent of D.M. The oats varieties were generally lowest followed by Stephens and Yamhill wheats, FB 73130 barley, VT 75-229 Triticale, Adair barley and Sel N-91 and S-72 Triticales. Covariance analysis indicated that a strong linear relationship existed between the yield and the quality components of the cereal varieties. When CP, ADF and NDF contents were adjusted for the same yield, it was found that the nitrogen fertilizer effect was no longer significant for either ADF or NDF. Title: Yield and quality of cereals for winter silage production Author: Ben Ali, Mohamed Noureddine A field study was conducted in 1978 and 1979 at two locations near Corvallis, Oregon, to determine the silage yield and quality of 13 fallsown cereal varieties at two nitrogen fertilizer levels in the context of a corn-winter cemal double cropping production system. Data on the yield, crude protein (CP) content, acid and neutral detergent fiber (ADF and NDF) contents were collected on Adair, Casbon and FB 73130 barley (Hordeum vulgare L.) varieties, Amity, Cayuse and Grey winter oats (Avena Sativa L.), Abruzi and Kung rye (Secale cereale L.), S-72, Sel N-91 and VT 75-229 Triticale (Triticum X Secale) and Stephens and Yamhill wheat (Triticum Aestivum L.) varieties. The statistical analysis of the data gave the following results. Dry matter yields ranged on the average from a high of 8327 kg/ha to a low of 4631 ka/ha. Abruzi rye generally yielded the most dry matter. It was followed by Sel N-91 and VT 75-229 Triticales, Kung rye, S-72 Triticale and the wheat varieties. The barley and oats varieties were generally the lowest producers. Crude protein content was within the range of 6,5 to 10.1 percent of the dry matter. It was on the average highest for FB 73130 barley followed by Casbon barley, Stephens wheat, Adair barley, Yamhill wheat and the Triticale varieties. Acid detergent fiber ranged from 30.8 to 46.4 percent of dry matter. The oats varieties had the lowest ADF values, followed by Stephens and Yamhill wheats, FB 73130 and Adair barleys and VT 75-229 Triticale. The average neutral detergent fiber content for the 13 cereal varieties varied from a low of 50.3 to a high of 69.4 percent of D.M. The oats varieties were generally lowest followed by Stephens and Yamhill wheats, FB 73130 barley, VT 75-229 Triticale, Adair barley and Sel N-91 and S-72 Triticales. Covariance analysis indicated that a strong linear relationship existed between the yield and the quality components of the cereal varieties. When CP, ADF and NDF contents were adjusted for the same yield, it was found that the nitrogen fertilizer effect was no longer significant for either ADF or NDF. Close

• 44. [Article] Estimating plant-available nitrogen release from cover crops

  Published November 2012. Reviewed October 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Estimating plant-available nitrogen release from cover crops Author: Andrews, N. (Nick), Oregon State University. Extension Service, Sullivan, Dan M. (Dan Matthew), 1954- Published November 2012. Reviewed October 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Estimating plant-available nitrogen release from cover crops Author: Andrews, N. (Nick), Oregon State University. Extension Service, Sullivan, Dan M. (Dan Matthew), 1954- Published November 2012. Reviewed October 2016. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 45. [Article] Economic evaluation of different cropping patterns under irrigated agriculture : a multidisciplinary approach

  The purpose of this study is to determine the socioeconomic factors which influence the profitability and adoption of new cropping patterns, and to recommend suitable measures to enhance the crop diversification program ...

  Citation × Citation Citation Abstract Copy Title: Economic evaluation of different cropping patterns under irrigated agriculture : a multidisciplinary approach Author: Mahrouf, Abdul R. M. The purpose of this study is to determine the socioeconomic factors which influence the profitability and adoption of new cropping patterns, and to recommend suitable measures to enhance the crop diversification program in Mahaweli System B, Sri Lanka. The adoption of new cropping patterns is determined by a number of interrelated and mutually reinforcing factors. Hence, a multidisciplinary approach is used in this study to apprehend the different attributes of the new cropping patterns and farmers' decision making environment. The analytical methods include Marginal Cost-Benefit Analysis, Multivariate Analysis of Variance, Factor Analysis and Logit Probability Model. The results from the different techniques are generally in close agreement and complement each other. Results of the Marginal Cost- Benefit Analysis indicates that an increase in current crop yields and output prices may be necessary to increase the profitability of new cropping patterns to a recommendable level. Analysis of the farmers' beliefs suggests that adopters of the new cropping patterns have more positive beliefs towards the profitability and adoption of new cropping patterns when compared to nonadopters. Factor Analysis shows that there is a wide variation between the adopters and non-adopters, and also across the different locations with respect to farm-level variables. The analysis demonstrated that the information provided by 17 selected farm-level variables may be explained by four factors; namely, management factor, social factor, farm resource factor and farm stability factor. The variables highly loaded with the stability factor (number of years of residence, amount of loan obtained for farming, irrigation condition and percentage of rice produced allocated for consumption) are closely associated with the adoption rate. A logit probability model indicates that availability of farm loans significantly increases the probability of the adoption of new cropping patterns. The study results show that the crop yield, output prices, availability of farm loans and farmer beliefs, are the dominant factors which influence the adoption of new cropping patterns. Title: Economic evaluation of different cropping patterns under irrigated agriculture : a multidisciplinary approach Author: Mahrouf, Abdul R. M. The purpose of this study is to determine the socioeconomic factors which influence the profitability and adoption of new cropping patterns, and to recommend suitable measures to enhance the crop diversification program in Mahaweli System B, Sri Lanka. The adoption of new cropping patterns is determined by a number of interrelated and mutually reinforcing factors. Hence, a multidisciplinary approach is used in this study to apprehend the different attributes of the new cropping patterns and farmers' decision making environment. The analytical methods include Marginal Cost-Benefit Analysis, Multivariate Analysis of Variance, Factor Analysis and Logit Probability Model. The results from the different techniques are generally in close agreement and complement each other. Results of the Marginal Cost- Benefit Analysis indicates that an increase in current crop yields and output prices may be necessary to increase the profitability of new cropping patterns to a recommendable level. Analysis of the farmers' beliefs suggests that adopters of the new cropping patterns have more positive beliefs towards the profitability and adoption of new cropping patterns when compared to nonadopters. Factor Analysis shows that there is a wide variation between the adopters and non-adopters, and also across the different locations with respect to farm-level variables. The analysis demonstrated that the information provided by 17 selected farm-level variables may be explained by four factors; namely, management factor, social factor, farm resource factor and farm stability factor. The variables highly loaded with the stability factor (number of years of residence, amount of loan obtained for farming, irrigation condition and percentage of rice produced allocated for consumption) are closely associated with the adoption rate. A logit probability model indicates that availability of farm loans significantly increases the probability of the adoption of new cropping patterns. The study results show that the crop yield, output prices, availability of farm loans and farmer beliefs, are the dominant factors which influence the adoption of new cropping patterns. Close

• 46. [Article] Effect of several apple rootstocks on growth, yield components and leaf area estimates on "Starkspur Supreme Delicious" trees

  Growth, yield components and leaf area were evaluated on 'Starkspur Supreme Delicious' apple on nine rootstocks: MAC 24, EMLA 7, EMLA 26, OAR 1, MAC 9, 0.3, EMLA 9, M 9, and EMLA 27. Estimates of planting ...

  Citation × Citation Citation Abstract Copy Title: Effect of several apple rootstocks on growth, yield components and leaf area estimates on "Starkspur Supreme Delicious" trees Author: Siller-Cepeda, Jorge H. Growth, yield components and leaf area were evaluated on 'Starkspur Supreme Delicious' apple on nine rootstocks: MAC 24, EMLA 7, EMLA 26, OAR 1, MAC 9, 0.3, EMLA 9, M 9, and EMLA 27. Estimates of planting density based on growth, estimates of leaf area based on four independent variables and the relationships among yield components, fruit quality, growth and leaf area were investigated during 1985. Tree height, tree spread and trunk cross sectional area were highest for trees on MAC 24 followed for EMLA 7 while trees on EMLA 26, OAR 1, MAC 9, 0.3, EMLA 9 and M 9 were less in these values in descending order, with the most dwarfing on EMLA 27. Estimates of planting densities indicated higher densities with tree canopy spread than TCSA based on standard trees of the age except on EMLA 27. The densities for trees on MAC 24 and EMLA 7 were estimated 426 and 496 trees/ha. respectively, while for the rootstocks with intermediate size ranged from 700 to 1000 trees/ha. The highest density was for EMLA 27 with 1824 trees/ha. Flower cluster, fruit number, yield and leaf area were highest in the least size controlling rootstocks MAC 24 and EMLA 7, and in general these were a function of tree size. MAC 9 had the highest flowering density, crop density and yield efficiency followed by 0.3, EMLA 26 and EMLA 9. Potential yields based on the estimated planting density were also highest for MAC 9. Fruit on OAR 1 had greatest soluble solids, firmest at harvest, but were the smallest. Fruit on EMLA 7 which had the lowest soluble solids were largest. A negative correlation between flowering density and fruit set among the rootstocks was found. Crop density influenced fruit size and weight. Fruit on EMLA 7, MAC 24 and EMLA 9 were the largest but these trees had the lowest crop density. There was a high correlation of fruit number with yield indicating this was the main component of yield. The leaf-fruit ratio was negatively correlated with flowering density, crop density and yield efficiency and the ratio was lowest on the more efficient rootstocks MAC 9, 0.3 and M 9 while those of MAC 24 and EMLA 7 were highest. No differences were seen among the regression lines of leaf area and 4 independent variables obtained from trees on various rootstocks and within rootstock. Fresh weight was the best estimate of leaf area but because of greater speed and simplicity, branch cross sectional area was chosen to predict leaf area. Total leaf area per tree decreased from the least size controlling rootstocks to the most dwarfing rootstocks. Tree leaf area index ranged from 1.69 in MAC 24 to 0.87 in 0.3, but it did not always increase proportionately to tree size. Orchard leaf area index from estimated planting densities showed low values in all rootstocks but a slight increase with the tree size. This indicated that trees at the estimated densities are not intercepting the maximum quantity of light. Title: Effect of several apple rootstocks on growth, yield components and leaf area estimates on "Starkspur Supreme Delicious" trees Author: Siller-Cepeda, Jorge H. Growth, yield components and leaf area were evaluated on 'Starkspur Supreme Delicious' apple on nine rootstocks: MAC 24, EMLA 7, EMLA 26, OAR 1, MAC 9, 0.3, EMLA 9, M 9, and EMLA 27. Estimates of planting density based on growth, estimates of leaf area based on four independent variables and the relationships among yield components, fruit quality, growth and leaf area were investigated during 1985. Tree height, tree spread and trunk cross sectional area were highest for trees on MAC 24 followed for EMLA 7 while trees on EMLA 26, OAR 1, MAC 9, 0.3, EMLA 9 and M 9 were less in these values in descending order, with the most dwarfing on EMLA 27. Estimates of planting densities indicated higher densities with tree canopy spread than TCSA based on standard trees of the age except on EMLA 27. The densities for trees on MAC 24 and EMLA 7 were estimated 426 and 496 trees/ha. respectively, while for the rootstocks with intermediate size ranged from 700 to 1000 trees/ha. The highest density was for EMLA 27 with 1824 trees/ha. Flower cluster, fruit number, yield and leaf area were highest in the least size controlling rootstocks MAC 24 and EMLA 7, and in general these were a function of tree size. MAC 9 had the highest flowering density, crop density and yield efficiency followed by 0.3, EMLA 26 and EMLA 9. Potential yields based on the estimated planting density were also highest for MAC 9. Fruit on OAR 1 had greatest soluble solids, firmest at harvest, but were the smallest. Fruit on EMLA 7 which had the lowest soluble solids were largest. A negative correlation between flowering density and fruit set among the rootstocks was found. Crop density influenced fruit size and weight. Fruit on EMLA 7, MAC 24 and EMLA 9 were the largest but these trees had the lowest crop density. There was a high correlation of fruit number with yield indicating this was the main component of yield. The leaf-fruit ratio was negatively correlated with flowering density, crop density and yield efficiency and the ratio was lowest on the more efficient rootstocks MAC 9, 0.3 and M 9 while those of MAC 24 and EMLA 7 were highest. No differences were seen among the regression lines of leaf area and 4 independent variables obtained from trees on various rootstocks and within rootstock. Fresh weight was the best estimate of leaf area but because of greater speed and simplicity, branch cross sectional area was chosen to predict leaf area. Total leaf area per tree decreased from the least size controlling rootstocks to the most dwarfing rootstocks. Tree leaf area index ranged from 1.69 in MAC 24 to 0.87 in 0.3, but it did not always increase proportionately to tree size. Orchard leaf area index from estimated planting densities showed low values in all rootstocks but a slight increase with the tree size. This indicated that trees at the estimated densities are not intercepting the maximum quantity of light. Close

• 47. [Article] Response of wheat (Triticum aestivum L.) cultivars and downy brome (Bromus tectorum L.) to metribuzin and ethyl metribuzin

  Downy brome (Bromus tectorum. L.), a serious grass weed in eastern Oregon can be partially controlled in wheat by metribuzin [4-amino-6-tertbutyl- 3-(methylthio)-as triazin -5(4H)-one]. However, cultivars ...

  Citation × Citation Citation Abstract Copy Title: Response of wheat (Triticum aestivum L.) cultivars and downy brome (Bromus tectorum L.) to metribuzin and ethyl metribuzin Author: Munir, Muhammad Downy brome (Bromus tectorum. L.), a serious grass weed in eastern Oregon can be partially controlled in wheat by metribuzin [4-amino-6-tertbutyl- 3-(methylthio)-as triazin -5(4H)-one]. However, cultivars of many crops Lave been reported to differ in their level of tolerance to metribuzin. This lack of tolerance has led to the investigation of other compounds, such as the ethylthio analog of metribuzin [4-amino-6-tert-butyI-3-(ethylthio)-as-triazin- 5(4H)-on], for selective control of downy brome in wheat. Greenhouse and growth chamber experiments on wheat, growing in soil or nutrient solution showed that: 1) GR50 values for Stephens, Hill 81, Yanahill, and Malcolm in soil were 0.41, 0.23, 0.25, and 0.44 kg/ha, respectively, for metribuzin and 1.89, 1.29, 1.37, and 1.97 kg/ha, respectively, for ethyl metribuzin; 2) GR50 values for these cultivars in nutrient solution were 3.26, 1.17, 1.32, and 3.87 uM, respectively, for metribuzin and 12.69, 7.20, 7.19, and 13.41 uM, respectively, for ethyl metribuzin; 3) Uptake of both herbicides.; by wheat was through the roots; 4) Cultivars did not show any differences in herbicide absorption from the nutrient solution. Therefore, differences in varietal tolerance may be are due to biochemical or physiological reasons, but are not due to differences in herbicide uptake. Increased growth at lower concentrations of these herbicides was observed in all cultivars studied. Metribuzin was five times more active than ethyl metribuzin. Both of these herbicides can be applied as an early postemergence treatment at the 3 leaf stage of wheat for effective control of downy brome. Yield components of the four cultivars were measured in response to metribuzin and ethyl metribuzin at two ecologically different sites. The susceptible cultivars (Hill 81 and Yamhill) showed greater injury in the lighter soils with high pH and lower organic matter content. Visual estimates of crop injury were generally higher than the actual reduction in final yield. Crop injury ratings up to 25% generally did not show a significant reduction in final grain yield. A positive correlation between protein content and concentration of these herbicides was noted. A study on the joint action of these two herbicides in the field and greenhouse showed that the combination of the two, increased the control of downy brome at lower rates. Their combined action was studied by using Colby's method and isobole method of Tammes. The reaction was calculated as additive. Downy brome was 8, 5, 5, and 9 times more sensitive to metribuzin and 6, 4, 4, and 6, times more sensitive to ethyl metribuzin than were the cultivars Stephens, Hill 81, Yamhill, and Malcolm, respectively. The use of these two herbicides to control downy brome in the cultivars Hill 81 and Yamhill should be avoided unless careful attention is given to soil properties and environmental conditions. Title: Response of wheat (Triticum aestivum L.) cultivars and downy brome (Bromus tectorum L.) to metribuzin and ethyl metribuzin Author: Munir, Muhammad Downy brome (Bromus tectorum. L.), a serious grass weed in eastern Oregon can be partially controlled in wheat by metribuzin [4-amino-6-tertbutyl- 3-(methylthio)-as triazin -5(4H)-one]. However, cultivars of many crops Lave been reported to differ in their level of tolerance to metribuzin. This lack of tolerance has led to the investigation of other compounds, such as the ethylthio analog of metribuzin [4-amino-6-tert-butyI-3-(ethylthio)-as-triazin- 5(4H)-on], for selective control of downy brome in wheat. Greenhouse and growth chamber experiments on wheat, growing in soil or nutrient solution showed that: 1) GR50 values for Stephens, Hill 81, Yanahill, and Malcolm in soil were 0.41, 0.23, 0.25, and 0.44 kg/ha, respectively, for metribuzin and 1.89, 1.29, 1.37, and 1.97 kg/ha, respectively, for ethyl metribuzin; 2) GR50 values for these cultivars in nutrient solution were 3.26, 1.17, 1.32, and 3.87 uM, respectively, for metribuzin and 12.69, 7.20, 7.19, and 13.41 uM, respectively, for ethyl metribuzin; 3) Uptake of both herbicides.; by wheat was through the roots; 4) Cultivars did not show any differences in herbicide absorption from the nutrient solution. Therefore, differences in varietal tolerance may be are due to biochemical or physiological reasons, but are not due to differences in herbicide uptake. Increased growth at lower concentrations of these herbicides was observed in all cultivars studied. Metribuzin was five times more active than ethyl metribuzin. Both of these herbicides can be applied as an early postemergence treatment at the 3 leaf stage of wheat for effective control of downy brome. Yield components of the four cultivars were measured in response to metribuzin and ethyl metribuzin at two ecologically different sites. The susceptible cultivars (Hill 81 and Yamhill) showed greater injury in the lighter soils with high pH and lower organic matter content. Visual estimates of crop injury were generally higher than the actual reduction in final yield. Crop injury ratings up to 25% generally did not show a significant reduction in final grain yield. A positive correlation between protein content and concentration of these herbicides was noted. A study on the joint action of these two herbicides in the field and greenhouse showed that the combination of the two, increased the control of downy brome at lower rates. Their combined action was studied by using Colby's method and isobole method of Tammes. The reaction was calculated as additive. Downy brome was 8, 5, 5, and 9 times more sensitive to metribuzin and 6, 4, 4, and 6, times more sensitive to ethyl metribuzin than were the cultivars Stephens, Hill 81, Yamhill, and Malcolm, respectively. The use of these two herbicides to control downy brome in the cultivars Hill 81 and Yamhill should be avoided unless careful attention is given to soil properties and environmental conditions. Close

• 48. [Article] Performance of Leucaena, sorghum or cowpea and resource sharing in an agrisilviculture system in semi-arid India

  In an agrisilviculture system, trees and crops compete for above and below ground resources. This study aimed at quantifying the effect of shoot pruning and root barriers around pollarded trees on the ...

  Citation × Citation Citation Abstract Copy Title: Performance of Leucaena, sorghum or cowpea and resource sharing in an agrisilviculture system in semi-arid India Author: Osman, Mohammed, 1960- In an agrisilviculture system, trees and crops compete for above and below ground resources. This study aimed at quantifying the effect of shoot pruning and root barriers around pollarded trees on the production of crop and tree components with and without application of fertilizer to the crop. Sorghum (1991 & 1992) and cowpea (1993 & 1994) were grown as intercrops with Lezicaena trees on a shallow red soil (alfisol) under rain fed conditions at Hyderabad, India. Crops grown with pruned trees had higher leaf area index and dry matter than did those with unpruned trees. The grain yield of sorghum was 76% and 39% of the pure crop yield (1553 kg ha⁻¹) with pruned and unpruned trees with no root barriers. The corresponding values for cowpea were 49% and 26% of the pure crop yield (1075 kg ha⁻¹). Intercropped sorghum and cowpea responded to fertilizer application more strongly than their respective pure crops, suggesting a need for fertilizer application in an agrisilvi-system. impact of root bamers was not significant on either crop. The study suggested that competition for light was stronger than for soil water. Straw and grain yield of sorghum, and dry matter yield of cowpea were found to be roughly proportional to the amount of light intercepted by the crop at harvest. Pruning of trees twice during the cropping season reduced tree diameter growth and branch and foliage yield compared to no pruning. Unpruned trees yielded 5643 kg ha⁻¹ yr⁻¹ of branches and foliage compared to 2028 kg ha⁻¹ yr⁻¹ by pruned trees. Pruning eliminated litter fall and nutrient input to the soil nutrient pool because pruned material was utilized as fodder. Unpruned trees contributed 103 kg of nitrogen and 6.4 kg of phosphorus per hectare annually to the soil nutrient pool through litter fall. During the cropping season, soil water content was higher near the surface in tree plots compared to pure crop plots. Tree transpiration declined only after more than half of the leaf area was removed. Pruning of roots to a depth of 60 cm caused no decline in transpiration suggesting trees can draw water equally well from deeper or shallow soil layers. The study highlighted the competitive interaction between trees and crops. The agrisilvi-system produced about 50% more biomass with unpruned trees than with pure crop or pure tree. Based on cash value (fodder yield equivalent) it would require 1.55 times as much land if trees and crops were grown separately compared to agrisilvi-system with unpruned trees. Soil nitrogen economy and stability of fodder and fuelwood production can be achieved with pollarded-unpruned leucaena trees in an agrisilvi-system but grain crop yields are severely depressed. Thus, there was little advantage of the agrisilvi-system over pure cropping for meeting the present and increasing demand of food production. For this agrisilvi-system to be adopted by subsistence farmers in India further refinements must be developed so that crop yields are maintained. Title: Performance of Leucaena, sorghum or cowpea and resource sharing in an agrisilviculture system in semi-arid India Author: Osman, Mohammed, 1960- In an agrisilviculture system, trees and crops compete for above and below ground resources. This study aimed at quantifying the effect of shoot pruning and root barriers around pollarded trees on the production of crop and tree components with and without application of fertilizer to the crop. Sorghum (1991 & 1992) and cowpea (1993 & 1994) were grown as intercrops with Lezicaena trees on a shallow red soil (alfisol) under rain fed conditions at Hyderabad, India. Crops grown with pruned trees had higher leaf area index and dry matter than did those with unpruned trees. The grain yield of sorghum was 76% and 39% of the pure crop yield (1553 kg ha⁻¹) with pruned and unpruned trees with no root barriers. The corresponding values for cowpea were 49% and 26% of the pure crop yield (1075 kg ha⁻¹). Intercropped sorghum and cowpea responded to fertilizer application more strongly than their respective pure crops, suggesting a need for fertilizer application in an agrisilvi-system. impact of root bamers was not significant on either crop. The study suggested that competition for light was stronger than for soil water. Straw and grain yield of sorghum, and dry matter yield of cowpea were found to be roughly proportional to the amount of light intercepted by the crop at harvest. Pruning of trees twice during the cropping season reduced tree diameter growth and branch and foliage yield compared to no pruning. Unpruned trees yielded 5643 kg ha⁻¹ yr⁻¹ of branches and foliage compared to 2028 kg ha⁻¹ yr⁻¹ by pruned trees. Pruning eliminated litter fall and nutrient input to the soil nutrient pool because pruned material was utilized as fodder. Unpruned trees contributed 103 kg of nitrogen and 6.4 kg of phosphorus per hectare annually to the soil nutrient pool through litter fall. During the cropping season, soil water content was higher near the surface in tree plots compared to pure crop plots. Tree transpiration declined only after more than half of the leaf area was removed. Pruning of roots to a depth of 60 cm caused no decline in transpiration suggesting trees can draw water equally well from deeper or shallow soil layers. The study highlighted the competitive interaction between trees and crops. The agrisilvi-system produced about 50% more biomass with unpruned trees than with pure crop or pure tree. Based on cash value (fodder yield equivalent) it would require 1.55 times as much land if trees and crops were grown separately compared to agrisilvi-system with unpruned trees. Soil nitrogen economy and stability of fodder and fuelwood production can be achieved with pollarded-unpruned leucaena trees in an agrisilvi-system but grain crop yields are severely depressed. Thus, there was little advantage of the agrisilvi-system over pure cropping for meeting the present and increasing demand of food production. For this agrisilvi-system to be adopted by subsistence farmers in India further refinements must be developed so that crop yields are maintained. Close

• 49. [Article] Observations on the purchase, inspection, and preparation of vegetables for group feeding at certain army air bases

  Since vegetables are of such importance in the nutrition of human beings, it is natural that they should play a large part in Army feeding. They are high in food value. The different kinds vary widely ...

  Citation × Citation Citation Abstract Copy Title: Observations on the purchase, inspection, and preparation of vegetables for group feeding at certain army air bases Author: McIntyre, Ethel Mae Since vegetables are of such importance in the nutrition of human beings, it is natural that they should play a large part in Army feeding. They are high in food value. The different kinds vary widely in their energy values; some-- like potatoes--are high in carbohydrates, others--like lettuce and cucumbers-- are low. Fresh or canned they are high in minerals and vitamins, low in protein and fat, and are valuable for bulk and palatability. When purchasing fresh produce it was necessary to know something of quality, appearance, and texture. Quality is made up of many characteristics-- some external, internal, chemical, and physical. Appearance is concerned with shape, color, freedom from blemishes and dirt. Texture contrasts hard or soft, smooth or granular, stringy and fibrous or free from fiber, crisp or flabby, wilted or tough. The flavor of vegetables is due to several constituents: sugar, organic acids, mineral salts, and aromatic compounds. A combination of these gives flavors that make vegetables palatable and attractive. The nutritive value of a given vegetable depends on the part of the plant to be used, as well, as the variety, climate, soil in which it is grown, conditions of storage, and preparation. The leaf, stem, flower, seed, and fruit are all edible parts. When purchasing vegetables for the Army it was well to know that the initial price was by no means the ultimate cost as there was a wide margin between the cost as purchased and edible-portion cost. Waste in preparation, storage, and losses in the cooking of highly perishable produce would cost six cents per pound as purchased and thirty cents per pound edible portion. The condition of the vegetables when delivered has a great influence on the probable yield. When purchasing canned vegetables, grades were used as purchasing guides. Samples of each grade of produce were requested for testing to find out if the product was satisfactory. The highest grade was not purchased for general use; Grade B or Standard was acceptable for the Army mess. Fresh and frozen vegetables were used largely in Army camps and fields in the United States. Canned and dehydrated products were to be used in combat areas overseas because they were easy to prepare, there was little or no waste, and the nutritive value was fairly well retained. The problem of storage was not difficult, and shipping space was saved when dehydrated food was shipped because of its lightness and lack of bulk. The Army food purchasing officer needed to be familiar with the local vegetable supply and market center facilities. A knowledge of standardizing, grading, packaging, sorting, and transporting produce was necessary in order to purchase food economically and intelligently. Because of uncertainty of crops due to curtailed planting and harvesting occasioned by labor shortages, it was difficult for producers and distributors to cooperate at all times. The Quartermaster's office arranged with local marketing centers for information on prices, substitutions, and quantities of local produce available, several days in advance, so that suitable substitutions could be made on menus if sufficient fresh vegetables were not obtainable. Inspection of all food on delivery was required, and if low grade or unsatisfactory produce was discovered it was returned to the dealers or an adjustment requested. This was done to determine whether or not supplies met the contract requirements for quality and conditions specified by the Army. Title: Observations on the purchase, inspection, and preparation of vegetables for group feeding at certain army air bases Author: McIntyre, Ethel Mae Since vegetables are of such importance in the nutrition of human beings, it is natural that they should play a large part in Army feeding. They are high in food value. The different kinds vary widely in their energy values; some-- like potatoes--are high in carbohydrates, others--like lettuce and cucumbers-- are low. Fresh or canned they are high in minerals and vitamins, low in protein and fat, and are valuable for bulk and palatability. When purchasing fresh produce it was necessary to know something of quality, appearance, and texture. Quality is made up of many characteristics-- some external, internal, chemical, and physical. Appearance is concerned with shape, color, freedom from blemishes and dirt. Texture contrasts hard or soft, smooth or granular, stringy and fibrous or free from fiber, crisp or flabby, wilted or tough. The flavor of vegetables is due to several constituents: sugar, organic acids, mineral salts, and aromatic compounds. A combination of these gives flavors that make vegetables palatable and attractive. The nutritive value of a given vegetable depends on the part of the plant to be used, as well, as the variety, climate, soil in which it is grown, conditions of storage, and preparation. The leaf, stem, flower, seed, and fruit are all edible parts. When purchasing vegetables for the Army it was well to know that the initial price was by no means the ultimate cost as there was a wide margin between the cost as purchased and edible-portion cost. Waste in preparation, storage, and losses in the cooking of highly perishable produce would cost six cents per pound as purchased and thirty cents per pound edible portion. The condition of the vegetables when delivered has a great influence on the probable yield. When purchasing canned vegetables, grades were used as purchasing guides. Samples of each grade of produce were requested for testing to find out if the product was satisfactory. The highest grade was not purchased for general use; Grade B or Standard was acceptable for the Army mess. Fresh and frozen vegetables were used largely in Army camps and fields in the United States. Canned and dehydrated products were to be used in combat areas overseas because they were easy to prepare, there was little or no waste, and the nutritive value was fairly well retained. The problem of storage was not difficult, and shipping space was saved when dehydrated food was shipped because of its lightness and lack of bulk. The Army food purchasing officer needed to be familiar with the local vegetable supply and market center facilities. A knowledge of standardizing, grading, packaging, sorting, and transporting produce was necessary in order to purchase food economically and intelligently. Because of uncertainty of crops due to curtailed planting and harvesting occasioned by labor shortages, it was difficult for producers and distributors to cooperate at all times. The Quartermaster's office arranged with local marketing centers for information on prices, substitutions, and quantities of local produce available, several days in advance, so that suitable substitutions could be made on menus if sufficient fresh vegetables were not obtainable. Inspection of all food on delivery was required, and if low grade or unsatisfactory produce was discovered it was returned to the dealers or an adjustment requested. This was done to determine whether or not supplies met the contract requirements for quality and conditions specified by the Army. Close

• 50. [Article] Feasibility of developing bread wheat cultivars with acceptable protein content for non-traditional areas

  The objective of this investigation was to evaluate the possibility of developing high yielding wheat cultivars whose flour would result in acceptable loaf volumes for non-traditional bread wheat growing ...

  Citation × Citation Citation Abstract Copy Title: Feasibility of developing bread wheat cultivars with acceptable protein content for non-traditional areas Author: Lorenzo, Ariel The objective of this investigation was to evaluate the possibility of developing high yielding wheat cultivars whose flour would result in acceptable loaf volumes for non-traditional bread wheat growing areas. Spring wheat germplasm employed included high protein hexaploid derivatives from Triticum dicoccoides, and selections from Argentina with good bread milling and baking properties. Winter wheat materials were from the Oregon State University International Winter x Spring Wheat Improvement Program. Elevated protein content was found not to be a prerequisite in obtaining high loaf volumes. Electrophoretic analysis (SDS-PAGE) of the high molecular weight glutenin subunits, and the sodium dodecyl sulphate sedimentation (SDSS) test proved to be reliable indicators of protein quality. High molecular weight glutenin banding patterns were independent of environmental factors. Bands 5-10 contributed by the D genome, with either bands 1 or 2* from the A genome and bands 7-8 or 17-18 coded by the B genome, appeared to be the most critical in influencing high loaf volume. For the experimental material used, SDSS values were found to be dependent upon variations in protein content. Five grams wholemeal flour samples with 2% SDS, 10 ml/I of 9.6% lactate solution and a reading time of 30 minutes provided the best combination to discriminate between lines with high or low loaf volume. Grain yield was found to be negatively associated with grain protein content in the spring wheat material. In crosses with Argentine lines, high protein "dicoccoides" derivatives, did not contribute major genes for protein content. Grain hardness was found to be a qualitatively inherited trait, and not associated with grain protein content or loaf volume. No single criterion proved of value in improving protein content and grain yield simultaneously, other than delaying selection until later generations. Strong negative associations between harvest index and grain protein content were observed for the winter wheat germplasm. Biological yield and kernel weight were the best selection criteria to improve grain protein without sacrificing grain yield. Early season applications of nitrate nitrogen resulted in a simultaneous increase in protein content and grain yield. Title: Feasibility of developing bread wheat cultivars with acceptable protein content for non-traditional areas Author: Lorenzo, Ariel The objective of this investigation was to evaluate the possibility of developing high yielding wheat cultivars whose flour would result in acceptable loaf volumes for non-traditional bread wheat growing areas. Spring wheat germplasm employed included high protein hexaploid derivatives from Triticum dicoccoides, and selections from Argentina with good bread milling and baking properties. Winter wheat materials were from the Oregon State University International Winter x Spring Wheat Improvement Program. Elevated protein content was found not to be a prerequisite in obtaining high loaf volumes. Electrophoretic analysis (SDS-PAGE) of the high molecular weight glutenin subunits, and the sodium dodecyl sulphate sedimentation (SDSS) test proved to be reliable indicators of protein quality. High molecular weight glutenin banding patterns were independent of environmental factors. Bands 5-10 contributed by the D genome, with either bands 1 or 2* from the A genome and bands 7-8 or 17-18 coded by the B genome, appeared to be the most critical in influencing high loaf volume. For the experimental material used, SDSS values were found to be dependent upon variations in protein content. Five grams wholemeal flour samples with 2% SDS, 10 ml/I of 9.6% lactate solution and a reading time of 30 minutes provided the best combination to discriminate between lines with high or low loaf volume. Grain yield was found to be negatively associated with grain protein content in the spring wheat material. In crosses with Argentine lines, high protein "dicoccoides" derivatives, did not contribute major genes for protein content. Grain hardness was found to be a qualitatively inherited trait, and not associated with grain protein content or loaf volume. No single criterion proved of value in improving protein content and grain yield simultaneously, other than delaying selection until later generations. Strong negative associations between harvest index and grain protein content were observed for the winter wheat germplasm. Biological yield and kernel weight were the best selection criteria to improve grain protein without sacrificing grain yield. Early season applications of nitrate nitrogen resulted in a simultaneous increase in protein content and grain yield. Close