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• 1. [Article] Controlling pocket gopher damage to agricultural crops

  Published February 1983. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/cata...

  Citation × Citation Citation Abstract Copy Title: Controlling pocket gopher damage to agricultural crops Author: DeCalesta, David S., Oregon State University. Extension Service Published February 1983. 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: Controlling pocket gopher damage to agricultural crops Author: DeCalesta, David S., Oregon State University. Extension Service Published February 1983. 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] Controlling pocket gopher damage to agricultural crops

  Published October 1990. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catal...

  Citation × Citation Citation Abstract Copy Title: Controlling pocket gopher damage to agricultural crops Author: Edge, W. Daniel, Oregon State University. Extension Service Published October 1990. 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: Controlling pocket gopher damage to agricultural crops Author: Edge, W. Daniel, Oregon State University. Extension Service Published October 1990. 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

• 3. [Article] Use of reactor cooling water from nuclear power plants for irrigation of agricultural crops; project completion report

  Citation × Citation Citation Abstract Copy Title: Use of reactor cooling water from nuclear power plants for irrigation of agricultural crops; project completion report Author: Rykbost, K. A., United States. Office of Water Resources Research, Boersma, L., Barlow, Edward William Ross Title: Use of reactor cooling water from nuclear power plants for irrigation of agricultural crops; project completion report Author: Rykbost, K. A., United States. Office of Water Resources Research, Boersma, L., Barlow, Edward William Ross Close

• 4. [Article] Controlling pocket gopher damage to agricultural crops

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

  Citation × Citation Citation Abstract Copy Title: Controlling pocket gopher damage to agricultural crops Author: Edge, W. Daniel, Oregon State University. Extension Service, Loegering, John P., 1964- Declared out of print December 2009. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Controlling pocket gopher damage to agricultural crops Author: Edge, W. Daniel, Oregon State University. Extension Service, Loegering, John P., 1964- Declared out of print December 2009. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 5. [Article] Snap beans and other commercial truck crops - agricultural statistics 1934 to 1943 - Oregon by counties preliminary release

  Published February 1944. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/cata...

  Citation × Citation Citation Abstract Copy Title: Snap beans and other commercial truck crops - agricultural statistics 1934 to 1943 - Oregon by counties preliminary release Author: Oregon State College. Federal Cooperative Extension Service Published February 1944. 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: Snap beans and other commercial truck crops - agricultural statistics 1934 to 1943 - Oregon by counties preliminary release Author: Oregon State College. Federal Cooperative Extension Service Published February 1944. 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

• 6. [Article] Effects of the northern root-knot nematode (Meloidogyne hapla Chitwood, 1949) on Mitcham peppermint (Mentha piperita L.) and Scotch spearmint (Mentha cardiaca Baker)

  The northern root-knot nematode (Meloidogyne hapla Chitwood, 1949) is a widespread pest on many plants in temperate zones such as the Pacific Northwest (U. S. A. ) Peppermint and spearmint are two major ...

  Citation × Citation Citation Abstract Copy Title: Effects of the northern root-knot nematode (Meloidogyne hapla Chitwood, 1949) on Mitcham peppermint (Mentha piperita L.) and Scotch spearmint (Mentha cardiaca Baker) Author: Eshtiaghi, Hassan The northern root-knot nematode (Meloidogyne hapla Chitwood, 1949) is a widespread pest on many plants in temperate zones such as the Pacific Northwest (U. S. A. ) Peppermint and spearmint are two major agricultural crops in Oregon and Washington with a combined annual acreage of 50, 000 to 55, 000 and an oil value of about 25 million dollars. Both plants are attacked by a number of natural enemies including some species of plant parasitic nematodes with M. hapla considered to be most destructive. A pathogenicity study which included fifteen different isolates of M. hapla, revealed that peppermint was a more susceptible host plant than spearmint. These nematode populations were collected from four major mint growing areas of the United States (Idaho, Indiana, Oregon and Washington) with most populations obtained from Oregon and Washington. Usually no symptoms appear on the above ground parts of root-knot nematode infected plants. Therefore, it is possible that farmers in these areas may overlook infected mint planting stock and introduce the pest into new lands. Spread of the nematode could cause serious problems in mint and many other agricultural crops. Inoculation of peppermint cuttings and rhizomes with different densities of nematode egg masses caused varying degrees of root gall formation in three and four month growing periods. Regression slopes indicated that the relationships between inoculum densities and root gall formation was significant at the one percent level. However, inoculated rhizomes and the longer growing period caused more infection in plants. A gradual decline in plant vigor and productivity could be attributed to root-knot nematode infection which resulted in a significant shoot length reduction and reduced plant weights. Dry matter contents and concentrations of N, P, Mn, Fe and Al decreased, but there was a slight increase in Ca. Spearmint rhizomes inoculated with fresh second stage larvae of M. hapla produced equally severe galling in four months of growth regardless of the various initial inoculum densities. However, no significant relationships between inoculum densities and reduction in plant weights or shoot lengths developed in this host. Decreases in dry matter contents of spearmint plants as well as concentrations of chemical elements were similar to those of peppermint. A deterrent interaction between the fungus Verticillium dahliae Kleb. and M. hapla was observed when peppermint and spearmint plants were inoculated with the two pathogens. Significantly (at the one percent level) less root galls were formed when V. dahliae was combined with different densities of M. hapla larvae. Also interaction between fungus and nematode caused longer incubation periods and less severe Verticillium wilt disease symptoms. Weight reductions due to such interaction were insignificant and the data indicate that peppermint was more susceptible to the pathogens than spearmint. It can be concluded that M. hapla can infect both peppermint and spearmint without showing obvious disease symptoms on aerial parts of plants. Therefore, infections can remain unnoticed particularly in spearmint which has more tolerance to the nematode Introduction of root-knot nematode infected planting stock to new planting sites or other fields spreads the parasite which will affect other agricultural crops. Also suppression of Verticillium wilt disease symptoms by the nematodes could complicate or delay early diagnosis and control of wilt disease. Title: Effects of the northern root-knot nematode (Meloidogyne hapla Chitwood, 1949) on Mitcham peppermint (Mentha piperita L.) and Scotch spearmint (Mentha cardiaca Baker) Author: Eshtiaghi, Hassan The northern root-knot nematode (Meloidogyne hapla Chitwood, 1949) is a widespread pest on many plants in temperate zones such as the Pacific Northwest (U. S. A. ) Peppermint and spearmint are two major agricultural crops in Oregon and Washington with a combined annual acreage of 50, 000 to 55, 000 and an oil value of about 25 million dollars. Both plants are attacked by a number of natural enemies including some species of plant parasitic nematodes with M. hapla considered to be most destructive. A pathogenicity study which included fifteen different isolates of M. hapla, revealed that peppermint was a more susceptible host plant than spearmint. These nematode populations were collected from four major mint growing areas of the United States (Idaho, Indiana, Oregon and Washington) with most populations obtained from Oregon and Washington. Usually no symptoms appear on the above ground parts of root-knot nematode infected plants. Therefore, it is possible that farmers in these areas may overlook infected mint planting stock and introduce the pest into new lands. Spread of the nematode could cause serious problems in mint and many other agricultural crops. Inoculation of peppermint cuttings and rhizomes with different densities of nematode egg masses caused varying degrees of root gall formation in three and four month growing periods. Regression slopes indicated that the relationships between inoculum densities and root gall formation was significant at the one percent level. However, inoculated rhizomes and the longer growing period caused more infection in plants. A gradual decline in plant vigor and productivity could be attributed to root-knot nematode infection which resulted in a significant shoot length reduction and reduced plant weights. Dry matter contents and concentrations of N, P, Mn, Fe and Al decreased, but there was a slight increase in Ca. Spearmint rhizomes inoculated with fresh second stage larvae of M. hapla produced equally severe galling in four months of growth regardless of the various initial inoculum densities. However, no significant relationships between inoculum densities and reduction in plant weights or shoot lengths developed in this host. Decreases in dry matter contents of spearmint plants as well as concentrations of chemical elements were similar to those of peppermint. A deterrent interaction between the fungus Verticillium dahliae Kleb. and M. hapla was observed when peppermint and spearmint plants were inoculated with the two pathogens. Significantly (at the one percent level) less root galls were formed when V. dahliae was combined with different densities of M. hapla larvae. Also interaction between fungus and nematode caused longer incubation periods and less severe Verticillium wilt disease symptoms. Weight reductions due to such interaction were insignificant and the data indicate that peppermint was more susceptible to the pathogens than spearmint. It can be concluded that M. hapla can infect both peppermint and spearmint without showing obvious disease symptoms on aerial parts of plants. Therefore, infections can remain unnoticed particularly in spearmint which has more tolerance to the nematode Introduction of root-knot nematode infected planting stock to new planting sites or other fields spreads the parasite which will affect other agricultural crops. Also suppression of Verticillium wilt disease symptoms by the nematodes could complicate or delay early diagnosis and control of wilt disease. Close

• 7. [Article] Evaluation of the FDA derived intervention levels and exposure rate of 0.4 µR/hr using NARAC Web Atmosphere and Diffusion Modeling System

  The Oregon Department of Energy has set up recommendations for agricultural crop and non-crop embargo zones following an accidental or purposeful radioactive release. Of special interest are the FDA’s ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of the FDA derived intervention levels and exposure rate of 0.4 µR/hr using NARAC Web Atmosphere and Diffusion Modeling System Author: Hay, Tristan Ryan The Oregon Department of Energy has set up recommendations for agricultural crop and non-crop embargo zones following an accidental or purposeful radioactive release. Of special interest are the FDA’s Derived Intervention Levels (DIL) and the state’s exposure limit of 0.4µR/hr. At the Oregon State University Emergency Response Research and Support Lab, NARAC Web Atmosphere and Diffusion Modeling System is used to generate consequences from possible radiation release accident scenarios. Using scenario and NARAC outputs, the DIL and exposure are calculated and compared to the recommended DIL and exposure limits. Analysis of these calculations reveals a wide assortment of dissimilarities in the recommended limits for which the embargo zones are set. Title: Evaluation of the FDA derived intervention levels and exposure rate of 0.4 µR/hr using NARAC Web Atmosphere and Diffusion Modeling System Author: Hay, Tristan Ryan The Oregon Department of Energy has set up recommendations for agricultural crop and non-crop embargo zones following an accidental or purposeful radioactive release. Of special interest are the FDA’s Derived Intervention Levels (DIL) and the state’s exposure limit of 0.4µR/hr. At the Oregon State University Emergency Response Research and Support Lab, NARAC Web Atmosphere and Diffusion Modeling System is used to generate consequences from possible radiation release accident scenarios. Using scenario and NARAC outputs, the DIL and exposure are calculated and compared to the recommended DIL and exposure limits. Analysis of these calculations reveals a wide assortment of dissimilarities in the recommended limits for which the embargo zones are set. Close

• 8. [Article] Vegetation characterization of three contrasting riparian areas : Williamette Valley, Oregon

  Much of the native riparian vegetation of the Willamette Valley, Oregon, has been replaced with agricultural crops or invasive non-native plant species. Detailed information about current Willamette Valley ...

  Citation × Citation Citation Abstract Copy Title: Vegetation characterization of three contrasting riparian areas : Williamette Valley, Oregon Author: McAllister, Lynne S., Dwire, Kathleen A., Griffith, Stephen M. Much of the native riparian vegetation of the Willamette Valley, Oregon, has been replaced with agricultural crops or invasive non-native plant species. Detailed information about current Willamette Valley riparian vegetation is generally lacking. Plant specie composition data are useful in a variety of applications, including condition assessment, environmental monitoring and restoration planning. The objective of this study was to characterize the vegetation of three contrasting riparian sites occurring in the Willamette Valley. W determined plant species composition and abundance at a non-cultivated herbaceous site and a cultivated site, both located along Lake Creek, an intermittent stream, and at a forested site located along the Calapooia River, a perennial stream. All sites were adjacent to intensively-managed perennial ryegrass seed production fields. Crop agriculture strongly encroached on the Lake Creek sites, whereas the Calapooia site had received little encroachment from agricultural coversion. At Lake Creek, we inventoried 32 species at the non-cultivated herbaceous site and 18 species at the cultivated site, most of which were non-native. The cultivated site was dominated by wetland-adapted species in the area closest to the creek where perennial ryegrass was absent. Approximately half of the species at the non-cultivated herbaceous site were facultative upland species, and the site was dominated by introduced pasture grasses. In contrast, the 53 species inventoried at the forested site were mostly native and wetland-adapted. The forested site was dominated by Poplus balsamifera ssp, trichocarap T. & G., Pseudotsuga menziessii (Mirbel) Franco, and Acer macrophyllum Pursh, with extensive shrub and herbaceous strata. Results show a range of vegetative conditions found in riparian areas of the Willamette Valley and reflect the influence of differing hydrologic regimes and agricultural impacts. Title: Vegetation characterization of three contrasting riparian areas : Williamette Valley, Oregon Author: McAllister, Lynne S., Dwire, Kathleen A., Griffith, Stephen M. Much of the native riparian vegetation of the Willamette Valley, Oregon, has been replaced with agricultural crops or invasive non-native plant species. Detailed information about current Willamette Valley riparian vegetation is generally lacking. Plant specie composition data are useful in a variety of applications, including condition assessment, environmental monitoring and restoration planning. The objective of this study was to characterize the vegetation of three contrasting riparian sites occurring in the Willamette Valley. W determined plant species composition and abundance at a non-cultivated herbaceous site and a cultivated site, both located along Lake Creek, an intermittent stream, and at a forested site located along the Calapooia River, a perennial stream. All sites were adjacent to intensively-managed perennial ryegrass seed production fields. Crop agriculture strongly encroached on the Lake Creek sites, whereas the Calapooia site had received little encroachment from agricultural coversion. At Lake Creek, we inventoried 32 species at the non-cultivated herbaceous site and 18 species at the cultivated site, most of which were non-native. The cultivated site was dominated by wetland-adapted species in the area closest to the creek where perennial ryegrass was absent. Approximately half of the species at the non-cultivated herbaceous site were facultative upland species, and the site was dominated by introduced pasture grasses. In contrast, the 53 species inventoried at the forested site were mostly native and wetland-adapted. The forested site was dominated by Poplus balsamifera ssp, trichocarap T. & G., Pseudotsuga menziessii (Mirbel) Franco, and Acer macrophyllum Pursh, with extensive shrub and herbaceous strata. Results show a range of vegetative conditions found in riparian areas of the Willamette Valley and reflect the influence of differing hydrologic regimes and agricultural impacts. Close

• 9. [Article] Evaluating honey bee colonies for pollination : a guide for growers and beekeepers

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

  Citation × Citation Citation Abstract Copy Title: Evaluating honey bee colonies for pollination : a guide for growers and beekeepers Author: Mayer, D. F., Washington State University. Cooperative Extension, Pacific Northwest Cooperative Extension, United States. Dept. of Agriculture, Fisher, Glenn C., Oregon State University. Extension Service, Burgett, D. M., University of Idaho. Cooperative Extension Service, Johansen, C. A. (Carl A.) Declared out of print July 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Evaluating honey bee colonies for pollination : a guide for growers and beekeepers Author: Mayer, D. F., Washington State University. Cooperative Extension, Pacific Northwest Cooperative Extension, United States. Dept. of Agriculture, Fisher, Glenn C., Oregon State University. Extension Service, Burgett, D. M., University of Idaho. Cooperative Extension Service, Johansen, C. A. (Carl A.) Declared out of print July 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 10. [Article] Estimating crop yield and production changes as a function of irrigation deficit based on watershed and county level data

  Response of agricultural crops to irrigation water deficit is well-understood at the field scale. Broader scale (watershed and county levels) studies have been less frequently performed. Data collection ...

  Citation × Citation Citation Abstract Copy Title: Estimating crop yield and production changes as a function of irrigation deficit based on watershed and county level data Author: Darakjian, Priscila Response of agricultural crops to irrigation water deficit is well-understood at the field scale. Broader scale (watershed and county levels) studies have been less frequently performed. Data collection at the field level for extensive areas is time consuming and expensive. The importance of studies at a broader scale for evaluating future scenarios of agricultural land use justifies exploring alternative approaches that produce reasonable results in a faster and more economical manner. The objective of this study was to verify the ability of coarser level data to provide general trends of changes in agricultural cropping patterns as a function of water use management in the Willamette basin. In this study, watershed and county level data were used to analyze broader scale crop water relationships, since these data are abundant and easily accessible. Further, future estimates of crop water use, based on estimates of yield and acreage changes , were attempted for a study period spanning current conditions (2000) through 2050. FAO Yield Response to Water Model was used to relate crop yield and production to applied irrigation water. Assumptions made to apply this model at the basin level related mostly to climatic factors and dynamic change of the system. Changes in maximum crop yield for all important crops grown in the Willamette basin were estimated using a logistic function parameterized with historic and current datasets. It was important to consider the dynamic system response when modeling the system to incorporate environmental, technological and socio-economic factors not reflected in the original model. The results for crop yield showed a decrease through time for sweet corn, stable yield for cherries, ryegrass, and grapes, and increasing yield for alfalfa, strawberries and raspberries. Crops showing higher sensitivity to water deficit included snap beans, winter and spring wheat, oats and filberts. Production estimates showed 3 groups of crops: predominantly successful (filberts, cherries, ryegrass, oats and spring wheat), stable (strawberries, alfalfa, orchardgrass, mint and fescue) and predominantly unsuccessful crops (winter wheat, sweet corn, snap beans and berries). County level and watershed level data proved helpful in developing a more comprehensive view of crop production and its irrigation deficit response, using models incorporating information from finer spatial scale experiments. Socio-economic, technologic and environmental variables that might influence agriculture over time should be investigated in further studies. Title: Estimating crop yield and production changes as a function of irrigation deficit based on watershed and county level data Author: Darakjian, Priscila Response of agricultural crops to irrigation water deficit is well-understood at the field scale. Broader scale (watershed and county levels) studies have been less frequently performed. Data collection at the field level for extensive areas is time consuming and expensive. The importance of studies at a broader scale for evaluating future scenarios of agricultural land use justifies exploring alternative approaches that produce reasonable results in a faster and more economical manner. The objective of this study was to verify the ability of coarser level data to provide general trends of changes in agricultural cropping patterns as a function of water use management in the Willamette basin. In this study, watershed and county level data were used to analyze broader scale crop water relationships, since these data are abundant and easily accessible. Further, future estimates of crop water use, based on estimates of yield and acreage changes , were attempted for a study period spanning current conditions (2000) through 2050. FAO Yield Response to Water Model was used to relate crop yield and production to applied irrigation water. Assumptions made to apply this model at the basin level related mostly to climatic factors and dynamic change of the system. Changes in maximum crop yield for all important crops grown in the Willamette basin were estimated using a logistic function parameterized with historic and current datasets. It was important to consider the dynamic system response when modeling the system to incorporate environmental, technological and socio-economic factors not reflected in the original model. The results for crop yield showed a decrease through time for sweet corn, stable yield for cherries, ryegrass, and grapes, and increasing yield for alfalfa, strawberries and raspberries. Crops showing higher sensitivity to water deficit included snap beans, winter and spring wheat, oats and filberts. Production estimates showed 3 groups of crops: predominantly successful (filberts, cherries, ryegrass, oats and spring wheat), stable (strawberries, alfalfa, orchardgrass, mint and fescue) and predominantly unsuccessful crops (winter wheat, sweet corn, snap beans and berries). County level and watershed level data proved helpful in developing a more comprehensive view of crop production and its irrigation deficit response, using models incorporating information from finer spatial scale experiments. Socio-economic, technologic and environmental variables that might influence agriculture over time should be investigated in further studies. Close

• 11. [Article] Biomass production from the US forest and agriculture sectors in support of a renewable electricity standard

  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 Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Biomass production from the US forest and agriculture sectors in support of a renewable electricity standard Author: White, Eric M., Alig, Ralph J., Latta, Greg, Skog, Kenneth E., Adams, Darius 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 Elsevier and can be found at: http://www.elsevier.com/. Title: Biomass production from the US forest and agriculture sectors in support of a renewable electricity standard Author: White, Eric M., Alig, Ralph J., Latta, Greg, Skog, Kenneth E., Adams, Darius 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 Elsevier and can be found at: http://www.elsevier.com/. Close

• 12. [Article] Deep soil nitrogen survey, Lower Umatilla Basin, Oregon

  Soils of 49 agricultural and 2 "native condition" sites in the Lower Umatilla Basin, Oregon were sampled for nitrate-nitrogen, ammonium-nitrogen, chloride, and pH beginning in Fall of 1992. Several sites ...

  Citation × Citation Citation Abstract Copy Title: Deep soil nitrogen survey, Lower Umatilla Basin, Oregon Author: del Nero, Zachary Augustus Soils of 49 agricultural and 2 "native condition" sites in the Lower Umatilla Basin, Oregon were sampled for nitrate-nitrogen, ammonium-nitrogen, chloride, and pH beginning in Fall of 1992. Several sites were sampled in Spring and Fall 1993 in order to indicate movement or loss of residual soil nitrogen over time. This study was prompted by current concern over contamination of public drinking water supplies by nitrate and the designation of over 550 square miles of this region as a Ground Water Management Area. This study sought to identify links between agricultural management practices-primarily irrigation, fertilization, and crop rotation systems, and deep soil nitrate levels. Soil profiles were divided into 3 "management zones:" 0-3', 3-6', and beyond 6' in depth. These depths represent average rooting depths for the major agricultural crops of the study area. In general, the effective rooting depth of most area-crops does not extend beyond 6', therefore, it was determined that residual soil-nitrate found at this depth or beyond may be a potential source of ground water contamination if not managed correctly. Results of the study indicate that proper management of irrigation, fertilization, and cropping rotation can significantly reduce the potential for contaminating ground water. Deep soil nitrate levels under most agricultural fields were consistent with the concept that some loss of nitrate below the root zone is inevitable, however, this condition can be minimized through intensive crop management. This study concludes that responsible management of agriculture can minimize impacts on ground water, while providing quality food and fiber products to an ever-growing population. In addition, more research is needed in the area of crop physiology and response to intensively managed systems. Such research may provide insight into more efficient methods of crop production and environmental protection. Title: Deep soil nitrogen survey, Lower Umatilla Basin, Oregon Author: del Nero, Zachary Augustus Soils of 49 agricultural and 2 "native condition" sites in the Lower Umatilla Basin, Oregon were sampled for nitrate-nitrogen, ammonium-nitrogen, chloride, and pH beginning in Fall of 1992. Several sites were sampled in Spring and Fall 1993 in order to indicate movement or loss of residual soil nitrogen over time. This study was prompted by current concern over contamination of public drinking water supplies by nitrate and the designation of over 550 square miles of this region as a Ground Water Management Area. This study sought to identify links between agricultural management practices-primarily irrigation, fertilization, and crop rotation systems, and deep soil nitrate levels. Soil profiles were divided into 3 "management zones:" 0-3', 3-6', and beyond 6' in depth. These depths represent average rooting depths for the major agricultural crops of the study area. In general, the effective rooting depth of most area-crops does not extend beyond 6', therefore, it was determined that residual soil-nitrate found at this depth or beyond may be a potential source of ground water contamination if not managed correctly. Results of the study indicate that proper management of irrigation, fertilization, and cropping rotation can significantly reduce the potential for contaminating ground water. Deep soil nitrate levels under most agricultural fields were consistent with the concept that some loss of nitrate below the root zone is inevitable, however, this condition can be minimized through intensive crop management. This study concludes that responsible management of agriculture can minimize impacts on ground water, while providing quality food and fiber products to an ever-growing population. In addition, more research is needed in the area of crop physiology and response to intensively managed systems. Such research may provide insight into more efficient methods of crop production and environmental protection. Close

• 13. [Article] Seed Traits and Genes Important for Translational Biology—Highlights from Recent Discoveries

  This is the publisher’s final pdf. The article is copyrighted by the Japanese Society of Plant Physiologists and published by Oxford University Press. It can be found at: http://pcp.oxfordjournals.org/. ...

  Citation × Citation Citation Abstract Copy Title: Seed Traits and Genes Important for Translational Biology—Highlights from Recent Discoveries Author: Martinez-Andujar, Cristina, Nonogaki, Hiroyuki, Martin, Ruth C. This is the publisher’s final pdf. The article is copyrighted by the Japanese Society of Plant Physiologists and published by Oxford University Press. It can be found at: http://pcp.oxfordjournals.org/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Seed Traits and Genes Important for Translational Biology—Highlights from Recent Discoveries Author: Martinez-Andujar, Cristina, Nonogaki, Hiroyuki, Martin, Ruth C. This is the publisher’s final pdf. The article is copyrighted by the Japanese Society of Plant Physiologists and published by Oxford University Press. It can be found at: http://pcp.oxfordjournals.org/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 14. [Article] Using Mitogenomic and Nuclear Ribosomal Sequence Data to Investigate the Phylogeny of the Xiphinema americanum Species Complex

  This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/.

  Citation × Citation Citation Abstract Copy Title: Using Mitogenomic and Nuclear Ribosomal Sequence Data to Investigate the Phylogeny of the Xiphinema americanum Species Complex Author: Peetz, Amy, Zasada, Inga A., Denver, Dee R., Howe, Dana K., Wilhelm, Larry J., Cheam, Daravuth, Smythe, Ashleigh B. This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/. Title: Using Mitogenomic and Nuclear Ribosomal Sequence Data to Investigate the Phylogeny of the Xiphinema americanum Species Complex Author: Peetz, Amy, Zasada, Inga A., Denver, Dee R., Howe, Dana K., Wilhelm, Larry J., Cheam, Daravuth, Smythe, Ashleigh B. This is the publisher’s final pdf. The article was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/. Close

• 15. [Article] Evaluation of feedstocks for cellulosic ethanol and bioproducts production in the Northwest

  Cellulosic ethanol production for transportation fuel is one source to help satisfy the increasing worldwide demand for energy and depletion of the fossil fuel supply. Evaluating potential production from ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of feedstocks for cellulosic ethanol and bioproducts production in the Northwest Author: Miller, Wesley C. (Wesley Clair) Cellulosic ethanol production for transportation fuel is one source to help satisfy the increasing worldwide demand for energy and depletion of the fossil fuel supply. Evaluating potential production from plants and waste in Oregon, Washington and Idaho is the purpose of this study. Reed Canary grass, Annual Ryegrass, wheat straw, corn cobs, corn pericarp, gorse and waste newspaper are studied. Except for the newspaper (an analogue of municipal solid waste), these are common agricultural crops or invasive plants which are adapted to this area, and most of the United States. This paper estimates the potential for production of ethanol from these feedstocks through an investigation of available cropland combined with laboratory research into ethanol yield from these materials. Laboratory data for the various feedstocks ranged up to 237kg/Mg (72 gallons/ton) of ethanol produced. Total Northwest cropland is 7,502,272 hectares (18,538,517 acres) with 2,638,955 hectares (6,520,793 acres) of that under irrigation. (2007 Census of Agriculture - County Data, 2008). Common gorse, Ulex europaeus L., was examined for amounts of ether, hexane, ethanol and steam extracts and cellulosic ethanol yield at different times of the year. The highest seasonal amount of each component was approximately double that of the lowest. Title: Evaluation of feedstocks for cellulosic ethanol and bioproducts production in the Northwest Author: Miller, Wesley C. (Wesley Clair) Cellulosic ethanol production for transportation fuel is one source to help satisfy the increasing worldwide demand for energy and depletion of the fossil fuel supply. Evaluating potential production from plants and waste in Oregon, Washington and Idaho is the purpose of this study. Reed Canary grass, Annual Ryegrass, wheat straw, corn cobs, corn pericarp, gorse and waste newspaper are studied. Except for the newspaper (an analogue of municipal solid waste), these are common agricultural crops or invasive plants which are adapted to this area, and most of the United States. This paper estimates the potential for production of ethanol from these feedstocks through an investigation of available cropland combined with laboratory research into ethanol yield from these materials. Laboratory data for the various feedstocks ranged up to 237kg/Mg (72 gallons/ton) of ethanol produced. Total Northwest cropland is 7,502,272 hectares (18,538,517 acres) with 2,638,955 hectares (6,520,793 acres) of that under irrigation. (2007 Census of Agriculture - County Data, 2008). Common gorse, Ulex europaeus L., was examined for amounts of ether, hexane, ethanol and steam extracts and cellulosic ethanol yield at different times of the year. The highest seasonal amount of each component was approximately double that of the lowest. Close

• 16. [Article] Identification and mapping of habitat types in the vicinity of Mount Tolman in eastern Washington

  Studies were conducted in the vicinity of Mount Tolman on the Colville Indian Reservation in eastern Washington in order to identify vegetation habitat types of the area. After field studies were completed, ...

  Citation × Citation Citation Abstract Copy Title: Identification and mapping of habitat types in the vicinity of Mount Tolman in eastern Washington Author: Wilson, Mary Loverna Studies were conducted in the vicinity of Mount Tolman on the Colville Indian Reservation in eastern Washington in order to identify vegetation habitat types of the area. After field studies were completed, Daubenmire's keys to habitat types of eastern Washington (1968, 1970) were used to determine habitat types of the area. On the basis of sampling results, eleven habitat types were identified and described. This information was used in conjunction with aerial photointerpretation to prepare a vegetation map. Daubenmire's baseline studies, from which the habitat type keys were developed, were conducted in pristine climax stands. The Mount Tolman study area vegetation has been subjected to human disturbance for many years. Agriculture, grazing, logging, mining, and urbanization have all had an impact on the natural vegetation of the area. It was of interest to see at what levels of disturbance it would still be possible to determine habitat types from remnant native vegetation. Steppe habitat types identified were Agropyron spicatum/Festuca idahoensis and Purshia tridentata/Agropyron spicatum. Very little vegetation representative of these habitat types remained in the study area because of conversion of most open land to either agricultural crops or pasture. Most steppe portions of the study area had been heavily grazed and supported disclimax vegetation dominated by Bromus tectorum and other weedy species. Four Pinus ponderosa habitat types were identified. They were Pinus ponderosa/Agropyron spicatum, Pinus ponderosa/Festuca idahoensis, Pinus ponderosa/Purshia tridentata, and Pinus ponderosa/Symphoricarpos albus. Together they composed 43 percent of the study area. Three other forest habitats, Pseudotsuga menziesii/Symphoricarpos albus, Pseudotsuga menziesii/Physocarpus malvaceus, and Abies grandis/Pachistima myrsinites, occupied 30 percent of the study area. Two riparian habitat types occurred consistently in the creek drainages. One of these was Crataegus douglasii/ Symphoricarpus albus, both the Crataegus phase, and Populus tremuloides phase; the other was Alnus incana/Lysichitum americanum. Using Daubenmire's keys, coupled with information about seral communities and successional patterns, proved to be effective in determining habitat types in all but the most disturbed sites. Title: Identification and mapping of habitat types in the vicinity of Mount Tolman in eastern Washington Author: Wilson, Mary Loverna Studies were conducted in the vicinity of Mount Tolman on the Colville Indian Reservation in eastern Washington in order to identify vegetation habitat types of the area. After field studies were completed, Daubenmire's keys to habitat types of eastern Washington (1968, 1970) were used to determine habitat types of the area. On the basis of sampling results, eleven habitat types were identified and described. This information was used in conjunction with aerial photointerpretation to prepare a vegetation map. Daubenmire's baseline studies, from which the habitat type keys were developed, were conducted in pristine climax stands. The Mount Tolman study area vegetation has been subjected to human disturbance for many years. Agriculture, grazing, logging, mining, and urbanization have all had an impact on the natural vegetation of the area. It was of interest to see at what levels of disturbance it would still be possible to determine habitat types from remnant native vegetation. Steppe habitat types identified were Agropyron spicatum/Festuca idahoensis and Purshia tridentata/Agropyron spicatum. Very little vegetation representative of these habitat types remained in the study area because of conversion of most open land to either agricultural crops or pasture. Most steppe portions of the study area had been heavily grazed and supported disclimax vegetation dominated by Bromus tectorum and other weedy species. Four Pinus ponderosa habitat types were identified. They were Pinus ponderosa/Agropyron spicatum, Pinus ponderosa/Festuca idahoensis, Pinus ponderosa/Purshia tridentata, and Pinus ponderosa/Symphoricarpos albus. Together they composed 43 percent of the study area. Three other forest habitats, Pseudotsuga menziesii/Symphoricarpos albus, Pseudotsuga menziesii/Physocarpus malvaceus, and Abies grandis/Pachistima myrsinites, occupied 30 percent of the study area. Two riparian habitat types occurred consistently in the creek drainages. One of these was Crataegus douglasii/ Symphoricarpus albus, both the Crataegus phase, and Populus tremuloides phase; the other was Alnus incana/Lysichitum americanum. Using Daubenmire's keys, coupled with information about seral communities and successional patterns, proved to be effective in determining habitat types in all but the most disturbed sites. Close

• 17. [Article] A review of episodes of zinc phosphide toxicosis in wild geese (Branta spp.) in Oregon (2004–2011)

  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 Sage and ...

  Citation × Citation Citation Abstract Copy Title: A review of episodes of zinc phosphide toxicosis in wild geese (Branta spp.) in Oregon (2004–2011) Author: Wolff, Peregrine L., Schuler, Krysten L., Bildfell, Rob J., Meteyer, Carol U., Rumbeiha, Wilson K., Gillin, Colin 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 Sage and can be found at: http://www.sagepub.com/home.nav. Title: A review of episodes of zinc phosphide toxicosis in wild geese (Branta spp.) in Oregon (2004–2011) Author: Wolff, Peregrine L., Schuler, Krysten L., Bildfell, Rob J., Meteyer, Carol U., Rumbeiha, Wilson K., Gillin, Colin 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 Sage and can be found at: http://www.sagepub.com/home.nav. Close

• 18. [Article] Pathogenicity of Phytophthora species from Oregon waterways

  Described as one of the most destructive pathogens of agricultural crops and forest trees, Phytophthora is a genus of microorganisms containing over 100 known species. Phytophthora alni has caused collar ...

  Citation × Citation Citation Abstract Copy Title: Pathogenicity of Phytophthora species from Oregon waterways Author: Navarro, Sarah M. Described as one of the most destructive pathogens of agricultural crops and forest trees, Phytophthora is a genus of microorganisms containing over 100 known species. Phytophthora alni has caused collar and root disease in alders throughout Europe and a form of the species has recently been isolated in North America. Red alder, Alnus rubra, is native to Oregon and has been reported to be suffering from dieback, which prompted a survey of their overall health as well as determining if P. alni was present. Over 1200 individual Phytophthora isolates were recovered in the survey, which are representative of 22 species and 2 taxa, including P. alni subsp. uniformis. High levels of mortality for red alder were not observed during the WORE survey, which suggests these Phytophthora species are not aggressive pathogens of red alder. In order to test the hypothesis that red alder is not susceptible to the twelve Phytophthora species recovered from western Oregon riparian ecosystems, a variety of pathogenicity tests were conducted. Twelve species of Phytophthora were selected from the Phytophthora species recovered from the western Oregon riparian ecosystem survey for pathogenicity testing. Red alder seedlings were selected for testing because they have adapted to survive in riparian ecosystems, which is where these Phytophthora species have been recovered. Pathogenicity tests conducted for this study demonstrated that the twelve Phytophthora species from the survey of riparian ecosystems were able to cause minor disease symptoms on red alder, but did not cause the same symptoms observed during the WORE survey. Phytophthora species have the potential to have global impacts on forest ecosystems, which can be mitigated by conducting research on indigenous species before they become global issues of forest health. Title: Pathogenicity of Phytophthora species from Oregon waterways Author: Navarro, Sarah M. Described as one of the most destructive pathogens of agricultural crops and forest trees, Phytophthora is a genus of microorganisms containing over 100 known species. Phytophthora alni has caused collar and root disease in alders throughout Europe and a form of the species has recently been isolated in North America. Red alder, Alnus rubra, is native to Oregon and has been reported to be suffering from dieback, which prompted a survey of their overall health as well as determining if P. alni was present. Over 1200 individual Phytophthora isolates were recovered in the survey, which are representative of 22 species and 2 taxa, including P. alni subsp. uniformis. High levels of mortality for red alder were not observed during the WORE survey, which suggests these Phytophthora species are not aggressive pathogens of red alder. In order to test the hypothesis that red alder is not susceptible to the twelve Phytophthora species recovered from western Oregon riparian ecosystems, a variety of pathogenicity tests were conducted. Twelve species of Phytophthora were selected from the Phytophthora species recovered from the western Oregon riparian ecosystem survey for pathogenicity testing. Red alder seedlings were selected for testing because they have adapted to survive in riparian ecosystems, which is where these Phytophthora species have been recovered. Pathogenicity tests conducted for this study demonstrated that the twelve Phytophthora species from the survey of riparian ecosystems were able to cause minor disease symptoms on red alder, but did not cause the same symptoms observed during the WORE survey. Phytophthora species have the potential to have global impacts on forest ecosystems, which can be mitigated by conducting research on indigenous species before they become global issues of forest health. Close

• 19. [Article] The evolution of agricultural resource use strategies in the Willamette Valley

  Agriculture in the Willamette Valley, Oregon, has undergone continual change since the annual migrations of American pioneer farmers began to arrive in the early 1840's. The comparisons of data from each ...

  Citation × Citation Citation Abstract Copy Title: The evolution of agricultural resource use strategies in the Willamette Valley Author: Blok, Jack H. Agriculture in the Willamette Valley, Oregon, has undergone continual change since the annual migrations of American pioneer farmers began to arrive in the early 1840's. The comparisons of data from each of the agricultural censuses of Oregon counties taken since 1850 confirms that change has been continual. The data revealed that the strategies of agricultural resource use employed by the valley's farmers, and which guided their agricultural practices, have also been continually modified or upgraded. The purpose of the study was to document the evolution of agricultural resource use strategies which were implemented in the Willamette Valley during the course of its growth and development. Two general assumptions were made that provided the organizational framework for the analysis. The agricultural resource use strategies were considered to have evolved from simpler to more complex forms, and agriculture was considered as a resource use system comparable to general systems. An analogy was made between the agricultural system of the Willamette Valley and a general system characterized by rapid growth and development. The development of the agricultural system was divided into a threefold chronology of growth stages. The analysis of changes in farm characteristics, total agricultural acreage, and crop and livestock production trends supported the threefold growth stage concept. Growth curves depicting data from each agricultural census on farm characteristics, agricultural acreage, crops, and livestock show several conspicuous similarities. On the basis of the similarities delimiting dates were selected for the theorized growth stages. Strategies favoring self-sufficing farms were predominan between 1840 and 1900. Strategies of diversified agricultural production prevailed between 1900 and 1950. In the third and current growth stage, beginning in 1950, farmers increasingly adopted strategies of highly specialized single enterprise farming at larger scales of operation. Once the growth stages' delimiting dates were decided upon they permitted an easier analysis of all the agricultural census data that was examined. The treatment of agriculture in the Willamette Valley as an open resource use system tied its structure and functioning to influences of simultaneous systematic developments occurring outside of agriculture. Title: The evolution of agricultural resource use strategies in the Willamette Valley Author: Blok, Jack H. Agriculture in the Willamette Valley, Oregon, has undergone continual change since the annual migrations of American pioneer farmers began to arrive in the early 1840's. The comparisons of data from each of the agricultural censuses of Oregon counties taken since 1850 confirms that change has been continual. The data revealed that the strategies of agricultural resource use employed by the valley's farmers, and which guided their agricultural practices, have also been continually modified or upgraded. The purpose of the study was to document the evolution of agricultural resource use strategies which were implemented in the Willamette Valley during the course of its growth and development. Two general assumptions were made that provided the organizational framework for the analysis. The agricultural resource use strategies were considered to have evolved from simpler to more complex forms, and agriculture was considered as a resource use system comparable to general systems. An analogy was made between the agricultural system of the Willamette Valley and a general system characterized by rapid growth and development. The development of the agricultural system was divided into a threefold chronology of growth stages. The analysis of changes in farm characteristics, total agricultural acreage, and crop and livestock production trends supported the threefold growth stage concept. Growth curves depicting data from each agricultural census on farm characteristics, agricultural acreage, crops, and livestock show several conspicuous similarities. On the basis of the similarities delimiting dates were selected for the theorized growth stages. Strategies favoring self-sufficing farms were predominan between 1840 and 1900. Strategies of diversified agricultural production prevailed between 1900 and 1950. In the third and current growth stage, beginning in 1950, farmers increasingly adopted strategies of highly specialized single enterprise farming at larger scales of operation. Once the growth stages' delimiting dates were decided upon they permitted an easier analysis of all the agricultural census data that was examined. The treatment of agriculture in the Willamette Valley as an open resource use system tied its structure and functioning to influences of simultaneous systematic developments occurring outside of agriculture. Close

• 20. [Article] Effect of livestock grazing on native bees in a Pacific Northwest bunchgrass prairie

  Native bees play an important role as pollinators of natural vegetation and agricultural crops. Yet many pollinators, including some native bees, are declining in numbers. Some of the potential causes ...

  Citation × Citation Citation Abstract Copy Title: Effect of livestock grazing on native bees in a Pacific Northwest bunchgrass prairie Author: Kimoto, Chiho Native bees play an important role as pollinators of natural vegetation and agricultural crops. Yet many pollinators, including some native bees, are declining in numbers. Some of the potential causes of these declines are habitat destruction and degradation by various human land uses, including urban development and sprawl, construction of roadways, and habitat conversion to agriculture such as crop production and livestock grazing. Livestock grazing is one of the most common land uses in western North America and it can impact floral and nesting resources that are important to native bees. These effects are likely manifested through grazing's effect on vegetation and soil characteristics. However, few studies have investigated how livestock grazing impacts native bees in North America. As a result, the overall goal of this research was to determine how a gradient of livestock grazing intensities impacts native bee communities in a threatened and poorly studied grassland of western North America, the Pacific Northwest Bunchgrass Prairie. Because no studies have examined the bee fauna of this grassland habitat, our study had two objectives: 1) describe the native bee community in the Zumwalt Prairie in northeastern Oregon, which is one of the largest remaining remnants of this unique grassland type, and how it changes through time, and 2) investigate how livestock grazing affects that native bee fauna. To address these objectives, we sampled pollinators during the summer of 2007 and 2008 in 16 40-ha pastures on a plateau in the Zumwalt Prairie using blue vane traps. Each pasture was assigned one of four cattle stocking rates (high, medium low, and no cattle), and grazing intensity was quantified by measuring utilization. Grazing treatments were applied in the early summer for two years. We measured soil and vegetation characteristics that related to floral and nesting resources of bees as well as several metrics of the bee community, including diversity, richness, abundance, and community composition. We found 92 species and 119 morphospecies of native bees in 27 genera. This diverse community of native bees showed strong interseasonal and interannual variation that appears to be related to weather and plant phenology. We also found that even after exposure to just two years of grazing, some effects on vegetation and soils were evident. For example, increased grazing intensity significantly reduced vegetation structure, the abundance of certain blooming plants, surface soil stability, and the amount of soil surface covered by herbaceous litter. In addition, increased grazing intensity significantly increased soil compaction and the amount of bare ground. Native bee communities responded grazing intensity through changes in abundance, richness, diversity and community composition. Different bee taxa responded to grazing intensity differently and this response varied temporally. For example, bumble bees were sensitive to grazing intensity early in the season, showing reduced abundance, diversity, and/or richness with increased grazing intensity. In contrast, halictid bees did not respond to grazing intensity in any season. However, even within a genus or family, different species responded to grazing intensity in different manners, potentially because of variation in life histories. This research suggests that maintaining land with a mixture of livestock grazing intensities may be the best way to conserve this important and diverse pollinator group in the Pacific Northwest Bunchgrass Prairie. Title: Effect of livestock grazing on native bees in a Pacific Northwest bunchgrass prairie Author: Kimoto, Chiho Native bees play an important role as pollinators of natural vegetation and agricultural crops. Yet many pollinators, including some native bees, are declining in numbers. Some of the potential causes of these declines are habitat destruction and degradation by various human land uses, including urban development and sprawl, construction of roadways, and habitat conversion to agriculture such as crop production and livestock grazing. Livestock grazing is one of the most common land uses in western North America and it can impact floral and nesting resources that are important to native bees. These effects are likely manifested through grazing's effect on vegetation and soil characteristics. However, few studies have investigated how livestock grazing impacts native bees in North America. As a result, the overall goal of this research was to determine how a gradient of livestock grazing intensities impacts native bee communities in a threatened and poorly studied grassland of western North America, the Pacific Northwest Bunchgrass Prairie. Because no studies have examined the bee fauna of this grassland habitat, our study had two objectives: 1) describe the native bee community in the Zumwalt Prairie in northeastern Oregon, which is one of the largest remaining remnants of this unique grassland type, and how it changes through time, and 2) investigate how livestock grazing affects that native bee fauna. To address these objectives, we sampled pollinators during the summer of 2007 and 2008 in 16 40-ha pastures on a plateau in the Zumwalt Prairie using blue vane traps. Each pasture was assigned one of four cattle stocking rates (high, medium low, and no cattle), and grazing intensity was quantified by measuring utilization. Grazing treatments were applied in the early summer for two years. We measured soil and vegetation characteristics that related to floral and nesting resources of bees as well as several metrics of the bee community, including diversity, richness, abundance, and community composition. We found 92 species and 119 morphospecies of native bees in 27 genera. This diverse community of native bees showed strong interseasonal and interannual variation that appears to be related to weather and plant phenology. We also found that even after exposure to just two years of grazing, some effects on vegetation and soils were evident. For example, increased grazing intensity significantly reduced vegetation structure, the abundance of certain blooming plants, surface soil stability, and the amount of soil surface covered by herbaceous litter. In addition, increased grazing intensity significantly increased soil compaction and the amount of bare ground. Native bee communities responded grazing intensity through changes in abundance, richness, diversity and community composition. Different bee taxa responded to grazing intensity differently and this response varied temporally. For example, bumble bees were sensitive to grazing intensity early in the season, showing reduced abundance, diversity, and/or richness with increased grazing intensity. In contrast, halictid bees did not respond to grazing intensity in any season. However, even within a genus or family, different species responded to grazing intensity in different manners, potentially because of variation in life histories. This research suggests that maintaining land with a mixture of livestock grazing intensities may be the best way to conserve this important and diverse pollinator group in the Pacific Northwest Bunchgrass Prairie. Close

• 21. [Article] IRCA and Oregon agricultural industries : nursery crops, Christmas trees, and strawberries in the Willamette Valley, and pears in the Hood River Valley

  Published April 1993. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog...

  Citation × Citation Citation Abstract Copy Title: IRCA and Oregon agricultural industries : nursery crops, Christmas trees, and strawberries in the Willamette Valley, and pears in the Hood River Valley Author: Mason, Robert George, Cross, Timothy L., Oregon State University. Agricultural Experiment Station, Nuckton, Carole Frank Published April 1993. 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: IRCA and Oregon agricultural industries : nursery crops, Christmas trees, and strawberries in the Willamette Valley, and pears in the Hood River Valley Author: Mason, Robert George, Cross, Timothy L., Oregon State University. Agricultural Experiment Station, Nuckton, Carole Frank Published April 1993. 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

• 22. [Article] Impact of land use patterns and agricultural practices on water quality in the Calapooia River Basin of western Oregon

  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 Soil and ...

  Citation × Citation Citation Abstract Copy Title: Impact of land use patterns and agricultural practices on water quality in the Calapooia River Basin of western Oregon Author: Giannico, G. R., Pfender, W.F., Whittaker, G.W., Garcia, T.S., Banowetz, G.M., Griffith, S.M., Mueller-Warrant, G.W. 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 Soil and Water Conservation Society and can be found at: http://www.jswconline.org/. Title: Impact of land use patterns and agricultural practices on water quality in the Calapooia River Basin of western Oregon Author: Giannico, G. R., Pfender, W.F., Whittaker, G.W., Garcia, T.S., Banowetz, G.M., Griffith, S.M., Mueller-Warrant, G.W. 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 Soil and Water Conservation Society and can be found at: http://www.jswconline.org/. Close

• 23. [Article] Factors affecting farmworkers' injuries due to use of pesticides in the United States and their relation to reentry time intervals

  More than 2.3 billion pounds of pesticides with a value of $4.1 billions are applied by farmworkers to agricultural crops each year. These chemicals applied to farm lands lead not only to acute and chronic ...

  Citation × Citation Citation Abstract Copy Title: Factors affecting farmworkers' injuries due to use of pesticides in the United States and their relation to reentry time intervals Author: Nemati, Gholam Reza More than 2.3 billion pounds of pesticides with a value of $4.1 billions are applied by farmworkers to agricultural crops each year. These chemicals applied to farm lands lead not only to acute and chronic health effects, they also enter the groundwater and food chain of populations. In recent years increased attention has been focused on the impact of pesticides on human health and the environment, as well as those who are in direct contact with pesticides, including farmworkers and workers in the chemical industry. Although many organizations, including the Environmental Protection Agency, the Occupational Safety and Health Administration, and the National Institute of Occupational Safety and Health, and others at the federal and state level, have attempted to control the safe use of pesticides, many cases of illness and injury due to pesticide poisoning are reported each year in the United States. The purpose of this study was to review the literature concerning injuries to farmworkers due to the use of pesticides over the last 20 years in the United States in order to determine which factors contribute to an increase or a decrease in the number and extent of these injuries. These factors are considered and conclusions are reached, based on the observations and the limitations of previously conducted studies of this issue. Injury to farmworkers due to pesticides is a multidimensional problem, solution of which is handicapped by a lack of documentation and evidence. The real number of injuries can not known, although estimates have been made. Moreover, there are extensive limitations to the determination of the extent of these injuries and their chronic health effects. Although data from case control and case report studies of farmworkers' injuries by pesticide poisoning could be used in order to reduce the number of poisonings and acute health effects, the application of these data for chronic effects are quit different. Most of the studies previously completed on the chronic health effects of pesticide poisoning are epidemiologic studies, utilizing data obtained from farm owners and growers, a population not as fully exposed to pesticide chemicals and their residues as farmworkers. Therefore, this data cannot be considered representative of farmworkers, or the seasonal and migrant workers who are in direct contact with these chemicals. In addition, data from these studies cannot be extrapolated to the general population, which is exposed to considerably lower levels of pesticides through the food chain and the environment. These factors make it difficult to accurately determine chronic health hazards resulting from pesticidal exposure, though it is certain that pesticide exposure constitutes a serious and acute health hazard for those in frequent and direct contact with the increased amount of pesticides in use in agriculture in the U.S. Title: Factors affecting farmworkers' injuries due to use of pesticides in the United States and their relation to reentry time intervals Author: Nemati, Gholam Reza More than 2.3 billion pounds of pesticides with a value of $4.1 billions are applied by farmworkers to agricultural crops each year. These chemicals applied to farm lands lead not only to acute and chronic health effects, they also enter the groundwater and food chain of populations. In recent years increased attention has been focused on the impact of pesticides on human health and the environment, as well as those who are in direct contact with pesticides, including farmworkers and workers in the chemical industry. Although many organizations, including the Environmental Protection Agency, the Occupational Safety and Health Administration, and the National Institute of Occupational Safety and Health, and others at the federal and state level, have attempted to control the safe use of pesticides, many cases of illness and injury due to pesticide poisoning are reported each year in the United States. The purpose of this study was to review the literature concerning injuries to farmworkers due to the use of pesticides over the last 20 years in the United States in order to determine which factors contribute to an increase or a decrease in the number and extent of these injuries. These factors are considered and conclusions are reached, based on the observations and the limitations of previously conducted studies of this issue. Injury to farmworkers due to pesticides is a multidimensional problem, solution of which is handicapped by a lack of documentation and evidence. The real number of injuries can not known, although estimates have been made. Moreover, there are extensive limitations to the determination of the extent of these injuries and their chronic health effects. Although data from case control and case report studies of farmworkers' injuries by pesticide poisoning could be used in order to reduce the number of poisonings and acute health effects, the application of these data for chronic effects are quit different. Most of the studies previously completed on the chronic health effects of pesticide poisoning are epidemiologic studies, utilizing data obtained from farm owners and growers, a population not as fully exposed to pesticide chemicals and their residues as farmworkers. Therefore, this data cannot be considered representative of farmworkers, or the seasonal and migrant workers who are in direct contact with these chemicals. In addition, data from these studies cannot be extrapolated to the general population, which is exposed to considerably lower levels of pesticides through the food chain and the environment. These factors make it difficult to accurately determine chronic health hazards resulting from pesticidal exposure, though it is certain that pesticide exposure constitutes a serious and acute health hazard for those in frequent and direct contact with the increased amount of pesticides in use in agriculture in the U.S. Close

• 24. [Article] Honey Bees (Apis mellifera) and Agricultural Chemicals: Global to Micro Perspectives

  Fungicide sensitivity of honey bee associated fungi Abstract - Honey bees are exposed to a wide range of pesticides while pollinating agricultural crops. These pesticides residues are found in beeswax, ...

  Citation × Citation Citation Abstract Copy Title: Honey Bees (Apis mellifera) and Agricultural Chemicals: Global to Micro Perspectives Author: Bernert, Ann Fungicide sensitivity of honey bee associated fungi Abstract - Honey bees are exposed to a wide range of pesticides while pollinating agricultural crops. These pesticides residues are found in beeswax, nectar and pollen in the hive. Some of the pesticides found are fungicides which are not generally considered harmful to insects. However, these fungicides may negatively impact mutualistic fungi associated with honey bees causing indirect harm to colony health. Fungi are implicated for helping break down complex protein molecules and therefore allowing the honey bees to attain more nutrients from the food source. The objective of this experiment was to identify if honey bee associated fungi were affected by fungicides that honey bees are exposed to. In order to achieve this objective, a number of fungi were isolated from bee bread and the honey bee digestive tract. Five of these isolates were genetically identified by sequencing of the internal transcriber spacer regions 1 and 4 and selected for fungicide sensitivity testing. Each fungal isolate was subject to five treatments with replications. With the exception of Mucor hiemalis, all fungal species growth was significantly reduced (p ≤ 0.05) by the fungicides chlorothalonil, iprodione, and boscalid at day 2 of exposure. This research suggests that while fungicides may not directly affect the honey, they may disrupt the normal balance of fungal associates in the hive. This imbalance may result in decreased nutritional attainment from bee bread thus indirectly affecting the health or behavior of the honey bee. More research is needed to identify the functional roles of fungi in honey bees. Tylosin & Fumagillin - Impacts on honey bee midgut bacterial symbionts Abstract- Concern for the managed honey bee population has been developing after drastic losses in the past decade. Suspected causes include new pests, pathogens, pesticides, migratory beekeeping, and nutritional deficiencies from a monoculture diet. To avoid the increasing threat of microbial pathogens, some beekeepers treat hives annually with tylosin and fumagillin, antibiotic compounds. Emerging research has identified the honey bee microbiome as an important aspect of colony health. It is unclear whether annual prophylactic treatments of tylosin and fumagillin applications deplete symbiotic microorganisms in the honey bee digestive tract. The purpose of this research was to gain an initial understanding if tylosin and fumagillin treatments significantly alter composition of Lactobacillus species in the honey bee midgut microbiome. Using a laboratory based, in vitro well-diffusion test and a caged in vivo experiment, four treatment groups consisting of 1) tylosin application, 2) fumagillin application, 3) tylosin with fumagillin application and 4) no chemical application as the control, were each replicated four times. Honey bees were sampled before treatment application, 5 days after treatment and 12 days after treatment. Midgut contents were then homogenized and concentration of Lactobacilli spp. in each midgut was assessed with a plate dilation series on MRS selective media. Colony Formation Units (CFU) were counted after plate inoculation and 72 hours of incubation. Proportions of high, medium and low CFU data were compared between treatment groups. Results suggest a need to further investigate the impact of annual antibiotic treatments and for a better understanding of the honey bee microbiome. Title: Honey Bees (Apis mellifera) and Agricultural Chemicals: Global to Micro Perspectives Author: Bernert, Ann Fungicide sensitivity of honey bee associated fungi Abstract - Honey bees are exposed to a wide range of pesticides while pollinating agricultural crops. These pesticides residues are found in beeswax, nectar and pollen in the hive. Some of the pesticides found are fungicides which are not generally considered harmful to insects. However, these fungicides may negatively impact mutualistic fungi associated with honey bees causing indirect harm to colony health. Fungi are implicated for helping break down complex protein molecules and therefore allowing the honey bees to attain more nutrients from the food source. The objective of this experiment was to identify if honey bee associated fungi were affected by fungicides that honey bees are exposed to. In order to achieve this objective, a number of fungi were isolated from bee bread and the honey bee digestive tract. Five of these isolates were genetically identified by sequencing of the internal transcriber spacer regions 1 and 4 and selected for fungicide sensitivity testing. Each fungal isolate was subject to five treatments with replications. With the exception of Mucor hiemalis, all fungal species growth was significantly reduced (p ≤ 0.05) by the fungicides chlorothalonil, iprodione, and boscalid at day 2 of exposure. This research suggests that while fungicides may not directly affect the honey, they may disrupt the normal balance of fungal associates in the hive. This imbalance may result in decreased nutritional attainment from bee bread thus indirectly affecting the health or behavior of the honey bee. More research is needed to identify the functional roles of fungi in honey bees. Tylosin & Fumagillin - Impacts on honey bee midgut bacterial symbionts Abstract- Concern for the managed honey bee population has been developing after drastic losses in the past decade. Suspected causes include new pests, pathogens, pesticides, migratory beekeeping, and nutritional deficiencies from a monoculture diet. To avoid the increasing threat of microbial pathogens, some beekeepers treat hives annually with tylosin and fumagillin, antibiotic compounds. Emerging research has identified the honey bee microbiome as an important aspect of colony health. It is unclear whether annual prophylactic treatments of tylosin and fumagillin applications deplete symbiotic microorganisms in the honey bee digestive tract. The purpose of this research was to gain an initial understanding if tylosin and fumagillin treatments significantly alter composition of Lactobacillus species in the honey bee midgut microbiome. Using a laboratory based, in vitro well-diffusion test and a caged in vivo experiment, four treatment groups consisting of 1) tylosin application, 2) fumagillin application, 3) tylosin with fumagillin application and 4) no chemical application as the control, were each replicated four times. Honey bees were sampled before treatment application, 5 days after treatment and 12 days after treatment. Midgut contents were then homogenized and concentration of Lactobacilli spp. in each midgut was assessed with a plate dilation series on MRS selective media. Colony Formation Units (CFU) were counted after plate inoculation and 72 hours of incubation. Proportions of high, medium and low CFU data were compared between treatment groups. Results suggest a need to further investigate the impact of annual antibiotic treatments and for a better understanding of the honey bee microbiome. Close

• 25. [Article] Computer simulation of a biomanagement system : the Mendocino County deer population in California

  Management of deer populations is directed toward multiple objectives. Deer populations on public and private lands belong to the public and thus management is a political process. Four components for ...

  Citation × Citation Citation Abstract Copy Title: Computer simulation of a biomanagement system : the Mendocino County deer population in California Author: Anderson, Frank M. Management of deer populations is directed toward multiple objectives. Deer populations on public and private lands belong to the public and thus management is a political process. Four components for an effective management system for deer populations are identified. These are the set of objectives relating to the resource, the set of regulations which will achieve the objectives, knowledge of the expected population response to alternative management strategies, and a means of monitoring these responses to determine whether or not the objectives are being achieved. Deer provide benefits mainly through the associated recreational opportunities and cause costs by interacting with land based economic activities such as agricultural crop production and reforestation. At certain times of the year deer may also compete with domestic livestock for forage. Deer also cause significant costs through collisions with automobiles on the highways. The extent of these benefits and costs, and others, is related to the biosystem through parameters such as the size and composition of the population, the extent of the hunting kill, and so on. In this thesis a computer simulation model of the Mendocino County, California, deer population is presented. The population is modeled as a density dependent birth and death process. Hunting strategies are potentially the most flexible management tool. Thus the model is structured to permit detailed examination of the response over time of the population to alternative hunting strategies. In California, a bucks-only hunting strategy has been followed since about the turn of the century. This study demonstrates that the bucks-only strategy neither effectively controls the size of the deer population, nor does it provide for the greatest recreational opportunities. The extent of the costs referred to above are directly related to the size of the population and the consumptive recreational benefits, that is those due to hunting, are directly related to the size of the hunting kill. Experiments with the model show that population control can be achieved and the hunting kill can be increased by a mixed buck and antlerless deer hunting strategy. Other results show that the computer simulation model can provide information about the biosystem which is not otherwise available. Simulation methods permit considerable insights into the operation and control of complex biosystems where the status of the systems is time dependent and the systems are influenced by uncontrollable elements so that at best the outcomes resulting from particular management actions are uncertain. The simulation model used in this study is applicable to other deer populations and other wildlife species. Title: Computer simulation of a biomanagement system : the Mendocino County deer population in California Author: Anderson, Frank M. Management of deer populations is directed toward multiple objectives. Deer populations on public and private lands belong to the public and thus management is a political process. Four components for an effective management system for deer populations are identified. These are the set of objectives relating to the resource, the set of regulations which will achieve the objectives, knowledge of the expected population response to alternative management strategies, and a means of monitoring these responses to determine whether or not the objectives are being achieved. Deer provide benefits mainly through the associated recreational opportunities and cause costs by interacting with land based economic activities such as agricultural crop production and reforestation. At certain times of the year deer may also compete with domestic livestock for forage. Deer also cause significant costs through collisions with automobiles on the highways. The extent of these benefits and costs, and others, is related to the biosystem through parameters such as the size and composition of the population, the extent of the hunting kill, and so on. In this thesis a computer simulation model of the Mendocino County, California, deer population is presented. The population is modeled as a density dependent birth and death process. Hunting strategies are potentially the most flexible management tool. Thus the model is structured to permit detailed examination of the response over time of the population to alternative hunting strategies. In California, a bucks-only hunting strategy has been followed since about the turn of the century. This study demonstrates that the bucks-only strategy neither effectively controls the size of the deer population, nor does it provide for the greatest recreational opportunities. The extent of the costs referred to above are directly related to the size of the population and the consumptive recreational benefits, that is those due to hunting, are directly related to the size of the hunting kill. Experiments with the model show that population control can be achieved and the hunting kill can be increased by a mixed buck and antlerless deer hunting strategy. Other results show that the computer simulation model can provide information about the biosystem which is not otherwise available. Simulation methods permit considerable insights into the operation and control of complex biosystems where the status of the systems is time dependent and the systems are influenced by uncontrollable elements so that at best the outcomes resulting from particular management actions are uncertain. The simulation model used in this study is applicable to other deer populations and other wildlife species. Close

• 26. [Article] Cereal Breeding and Production Symposium : Lima, Peru, March 23-30, 1981

  Published March 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog...

  Citation × Citation Citation Abstract Copy Title: Cereal Breeding and Production Symposium : Lima, Peru, March 23-30, 1981 Author: United States. Agency for International Development, Oregon State University. Agricultural Experiment Station, Universidad Nacional Agraria. Programa de Cereales, Oregon State University. Dept. of Crop Science. Published March 1982. 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: Cereal Breeding and Production Symposium : Lima, Peru, March 23-30, 1981 Author: United States. Agency for International Development, Oregon State University. Agricultural Experiment Station, Universidad Nacional Agraria. Programa de Cereales, Oregon State University. Dept. of Crop Science. Published March 1982. 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

• 27. [Article] Effects of pollen collected by honey bees from pollination dependent agricultural cropping systems on honey bee nutrition

  Managed honey bee (Apis mellifera L.) colonies are important pollinators of many cultivated crops. Honey bee colony declines averaging 30% annually in the United States for the past 7 years have caused ...

  Citation × Citation Citation Abstract Copy Title: Effects of pollen collected by honey bees from pollination dependent agricultural cropping systems on honey bee nutrition Author: Topitzhofer, Ellen Managed honey bee (Apis mellifera L.) colonies are important pollinators of many cultivated crops. Honey bee colony declines averaging 30% annually in the United States for the past 7 years have caused significant concern and hence have been a topic of intensive investigation. These declines are reportedly due to multiple factors. Poor nutrition, which may be a result of current migratory pollination practices, is one such factor. Migratory pollination is a common practice of beekeepers from the Pacific Northwest and involves the placement of managed honey bee colonies within a series of cropping systems. There is a gap in knowledge on how migratory pollination practices impact honey bee nutrition. To understand the potential impacts of migratory pollination on honey bee nutrition, it is critical to assess the diversity of pollen collected by bees when colonies are placed adjacent to these cropping systems. In this study, we describe the diversity of pollen collected by honey bee colonies managed by beekeepers in the Pacific Northwest region of the United States when placed in seven major cropping systems. We quantified the percent of target crop pollen and overall diversity of pollen collected by honey bees when colonies were placed in these cropping systems. We collected and identified pollen in almond (Prunus dulcis (Mill.)), cherry (Prunus avium L.), highbush blueberry (Vaccinium corymbosum L.), meadowfoam (Limnanthes alba Benth.), white clover (Trifolium repens L.), radish (Raphanus sativus L.), and carrot (Daucus carota (Hoffm.)) cropping systems. We found that pollen collected from colonies placed in almond cropping systems was predominately Prunus sp., and hence, low in pollen diversity. At the other end of the spectrum, pollen collected from colonies placed adjacent to blueberry cropping systems did not yield any target pollen types (Highbush blueberry, Vaccinium corymbosum L.), but was high in overall pollen diversity. The pollen collected from colonies placed in other cropping systems was largely intermediate in diversity between these two extremes. There were not many plant species in bloom when pollen was collected from colonies placed in almond cropping system, whereas more plants were in bloom when we collected pollen from colonies placed in blueberry cropping system. The results of this study demonstrate that honey bees collected pollen from plants in the surrounding environment and collected different degrees of pollen diversity across different cropping systems in which the colonies were placed. We further determined if pollen diversity influences colony-level protein utilization and biosynthesis of protein in nurse bees by conducting a pollen feeding experiment. Pollen collected from four different cropping systems in the first study was used to formulate four different diets, each varying in pollen diversity. We measured protein consumption in experimental colonies and by sampling nurse bees from each colony to estimate hypopharyngeal gland protein content and proteolytic enzyme activity after five weeks of feeding on the experimental pollen diets. Experimental colonies fed on pollen collected from almond cropping system exhibited a high protein consumption rate. However, low protein content as found in hypopharyngeal glands of nurse bees in these colonies. The nurse bees in these colonies also had low proteolytic enzyme activity, which indicates a lower rate of protein digestion. Overall, these results suggest that the diet representing pollen collected from almond cropping systems had low digestion rate and may have resulted in lower nurse bee hypopharyngeal gland protein. However, we cannot say this with certainty, as there were other confounding factors involved, such as presence of pesticides in the pollen collected from the cropping systems. Title: Effects of pollen collected by honey bees from pollination dependent agricultural cropping systems on honey bee nutrition Author: Topitzhofer, Ellen Managed honey bee (Apis mellifera L.) colonies are important pollinators of many cultivated crops. Honey bee colony declines averaging 30% annually in the United States for the past 7 years have caused significant concern and hence have been a topic of intensive investigation. These declines are reportedly due to multiple factors. Poor nutrition, which may be a result of current migratory pollination practices, is one such factor. Migratory pollination is a common practice of beekeepers from the Pacific Northwest and involves the placement of managed honey bee colonies within a series of cropping systems. There is a gap in knowledge on how migratory pollination practices impact honey bee nutrition. To understand the potential impacts of migratory pollination on honey bee nutrition, it is critical to assess the diversity of pollen collected by bees when colonies are placed adjacent to these cropping systems. In this study, we describe the diversity of pollen collected by honey bee colonies managed by beekeepers in the Pacific Northwest region of the United States when placed in seven major cropping systems. We quantified the percent of target crop pollen and overall diversity of pollen collected by honey bees when colonies were placed in these cropping systems. We collected and identified pollen in almond (Prunus dulcis (Mill.)), cherry (Prunus avium L.), highbush blueberry (Vaccinium corymbosum L.), meadowfoam (Limnanthes alba Benth.), white clover (Trifolium repens L.), radish (Raphanus sativus L.), and carrot (Daucus carota (Hoffm.)) cropping systems. We found that pollen collected from colonies placed in almond cropping systems was predominately Prunus sp., and hence, low in pollen diversity. At the other end of the spectrum, pollen collected from colonies placed adjacent to blueberry cropping systems did not yield any target pollen types (Highbush blueberry, Vaccinium corymbosum L.), but was high in overall pollen diversity. The pollen collected from colonies placed in other cropping systems was largely intermediate in diversity between these two extremes. There were not many plant species in bloom when pollen was collected from colonies placed in almond cropping system, whereas more plants were in bloom when we collected pollen from colonies placed in blueberry cropping system. The results of this study demonstrate that honey bees collected pollen from plants in the surrounding environment and collected different degrees of pollen diversity across different cropping systems in which the colonies were placed. We further determined if pollen diversity influences colony-level protein utilization and biosynthesis of protein in nurse bees by conducting a pollen feeding experiment. Pollen collected from four different cropping systems in the first study was used to formulate four different diets, each varying in pollen diversity. We measured protein consumption in experimental colonies and by sampling nurse bees from each colony to estimate hypopharyngeal gland protein content and proteolytic enzyme activity after five weeks of feeding on the experimental pollen diets. Experimental colonies fed on pollen collected from almond cropping system exhibited a high protein consumption rate. However, low protein content as found in hypopharyngeal glands of nurse bees in these colonies. The nurse bees in these colonies also had low proteolytic enzyme activity, which indicates a lower rate of protein digestion. Overall, these results suggest that the diet representing pollen collected from almond cropping systems had low digestion rate and may have resulted in lower nurse bee hypopharyngeal gland protein. However, we cannot say this with certainty, as there were other confounding factors involved, such as presence of pesticides in the pollen collected from the cropping systems. Close

• 28. [Article] Reunion technique sur l'amélioration des céréales 12-16 avril, 1982

  Published December 1982. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/cata...

  Citation × Citation Citation Abstract Copy Title: Reunion technique sur l'amélioration des céréales 12-16 avril, 1982 Author: United States. Agency for International Development, Institut national agronomique de Tunisie, Oregon State University. Agricultural Experiment Station Published December 1982. 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: Reunion technique sur l'amélioration des céréales 12-16 avril, 1982 Author: United States. Agency for International Development, Institut national agronomique de Tunisie, Oregon State University. Agricultural Experiment Station Published December 1982. 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

• 29. [Article] Use of MIKE SHE for estimation of evapotranspiration in the Sprague River Basin

  MIKE SHE is a fully distributed, physically-based hydrologic model that can simulate water movement over and under the Earth's surface. Evapotranspiration (ET) is one of the components of this model. MIKE ...

  Citation × Citation Citation Abstract Copy Title: Use of MIKE SHE for estimation of evapotranspiration in the Sprague River Basin Author: Shakya, Suva R. MIKE SHE is a fully distributed, physically-based hydrologic model that can simulate water movement over and under the Earth's surface. Evapotranspiration (ET) is one of the components of this model. MIKE SHE uses a modification of the Kristensen -Jensen (1975) method to calculate actual ET. This method is based on addition of the three evapotranspiration components – interception storage, transpiration by the plant and evaporation from the soil surface, to compute total actual evapotranspiration. The validity of the Kristensen-Jensen method has been tested on an arid region within the Sprague River subbasin of the Upper Klamath basin in southern Oregon. The model was setup on a 1,000 m by 1,000 m flat surface as a one-dimensional grid cell. There are sixteen computation layers which make three soil profile layers with varying soil properties. Meteorological data from the Pacific Northwest Cooperative Agricultural Weather Network (AgriMet) were used to setup the model. Soil physical properties were taken from the Soil Survey Geographic (SSURGO) database of the Natural Resources Conservation Service (NRCS). Values of the van Genuchten parameters for soil water retention and hydraulic conductivity as a function of soil texture from Carsel and Parrish (1988) were applied. Wetland vegetation such as duckweed and cattail, natural vegetation such as big sagebrush, ponderosa pine and juniper, and agricultural crops such as grass pasture and maize were used to test MIKE SHE evapotranspiration simulation. The length of growth stage, crop coefficient, leaf area index (LAI) and root depth values were taken from the literature. Actual crop ET rates were calculated based on AgriMet reference ET which uses the Kimberly Penman (Wright, 1982) method. The alfalfa reference ET was converted to a grass reference by multiplying by a factor of 0.833 (Jensen et al., 1990). The single crop coefficient method was used and soil stress was accounted for using the FAO 56 method (Allen et al, 1998). Simulated irrigation was applied to maize and grass to keep the root zone soil moisture close to field capacity. Crop ET rates from the MIKE SHE simulation were then compared to the AgriMet based ET rates, resulting in a comparison of Kristensen-Jensen method against the Kimberly Penman method. Both the Kristensen-Jensen and AgriMet simulation scenarios were driven by the same reference ET and the same FAO 56 basal crop coefficient. Differences are therefore a function of different methods for dealing with soil moisture stress. Results indicate that the MIKE SHE simulated evapotranspiration corresponds to the Kimberly Penman method for the duckweed and cattail wetlands species with resulting Nash and Sutcliffe (NS) efficiencies of 0.97 and 1.00, respectively. The big sagebrush, juniper, and ponderosa pine species required a soil stress correction factor for the crop coefficients and the results yielded NS efficiency values of 0.14, 0.59 and 0.68, respectively. Irrigation was automatically turned on for maize at a 20 percent soil moisture deficit to minimize the effects of water stress and the resulting NS efficiency was 0.85. For pasture, an irrigation based on average monthly water deficit for pasture in Klamath was used (Cuenca et al.,1992). This resulted in a NS efficiency of 0.77. Each crop requires unique treatment within the model. Required vegetation parameters such as crop coefficient and LAI, climatic factors such as reference ET, and soil hydraulic properties need to be based on local conditions to the extent possible. It should be noted that the MIKE SHE simulations were run in a one-dimensional mode which precluded accounting for spatial variability or lateral flow of surface or groundwater. The simulation results indicate that converting the study area into a well irrigated pasture would require application of substantial amounts of irrigation water by sprinkler or flooding. Wetlands would require even more water to flood the land, but would be well suited for development of regional habitat. Big sagebrush, juniper and ponderosa pine survive under natural conditions but experience considerable plant stress brought on by soil water deficits which limit plant production below the maximum possible growth. Title: Use of MIKE SHE for estimation of evapotranspiration in the Sprague River Basin Author: Shakya, Suva R. MIKE SHE is a fully distributed, physically-based hydrologic model that can simulate water movement over and under the Earth's surface. Evapotranspiration (ET) is one of the components of this model. MIKE SHE uses a modification of the Kristensen -Jensen (1975) method to calculate actual ET. This method is based on addition of the three evapotranspiration components – interception storage, transpiration by the plant and evaporation from the soil surface, to compute total actual evapotranspiration. The validity of the Kristensen-Jensen method has been tested on an arid region within the Sprague River subbasin of the Upper Klamath basin in southern Oregon. The model was setup on a 1,000 m by 1,000 m flat surface as a one-dimensional grid cell. There are sixteen computation layers which make three soil profile layers with varying soil properties. Meteorological data from the Pacific Northwest Cooperative Agricultural Weather Network (AgriMet) were used to setup the model. Soil physical properties were taken from the Soil Survey Geographic (SSURGO) database of the Natural Resources Conservation Service (NRCS). Values of the van Genuchten parameters for soil water retention and hydraulic conductivity as a function of soil texture from Carsel and Parrish (1988) were applied. Wetland vegetation such as duckweed and cattail, natural vegetation such as big sagebrush, ponderosa pine and juniper, and agricultural crops such as grass pasture and maize were used to test MIKE SHE evapotranspiration simulation. The length of growth stage, crop coefficient, leaf area index (LAI) and root depth values were taken from the literature. Actual crop ET rates were calculated based on AgriMet reference ET which uses the Kimberly Penman (Wright, 1982) method. The alfalfa reference ET was converted to a grass reference by multiplying by a factor of 0.833 (Jensen et al., 1990). The single crop coefficient method was used and soil stress was accounted for using the FAO 56 method (Allen et al, 1998). Simulated irrigation was applied to maize and grass to keep the root zone soil moisture close to field capacity. Crop ET rates from the MIKE SHE simulation were then compared to the AgriMet based ET rates, resulting in a comparison of Kristensen-Jensen method against the Kimberly Penman method. Both the Kristensen-Jensen and AgriMet simulation scenarios were driven by the same reference ET and the same FAO 56 basal crop coefficient. Differences are therefore a function of different methods for dealing with soil moisture stress. Results indicate that the MIKE SHE simulated evapotranspiration corresponds to the Kimberly Penman method for the duckweed and cattail wetlands species with resulting Nash and Sutcliffe (NS) efficiencies of 0.97 and 1.00, respectively. The big sagebrush, juniper, and ponderosa pine species required a soil stress correction factor for the crop coefficients and the results yielded NS efficiency values of 0.14, 0.59 and 0.68, respectively. Irrigation was automatically turned on for maize at a 20 percent soil moisture deficit to minimize the effects of water stress and the resulting NS efficiency was 0.85. For pasture, an irrigation based on average monthly water deficit for pasture in Klamath was used (Cuenca et al.,1992). This resulted in a NS efficiency of 0.77. Each crop requires unique treatment within the model. Required vegetation parameters such as crop coefficient and LAI, climatic factors such as reference ET, and soil hydraulic properties need to be based on local conditions to the extent possible. It should be noted that the MIKE SHE simulations were run in a one-dimensional mode which precluded accounting for spatial variability or lateral flow of surface or groundwater. The simulation results indicate that converting the study area into a well irrigated pasture would require application of substantial amounts of irrigation water by sprinkler or flooding. Wetlands would require even more water to flood the land, but would be well suited for development of regional habitat. Big sagebrush, juniper and ponderosa pine survive under natural conditions but experience considerable plant stress brought on by soil water deficits which limit plant production below the maximum possible growth. Close

• 30. [Article] Nutrient Profile and Nursery Feeding Damage of Halyomorpha halys (Hempitera: Pentatomidae)

  Halyomorpha halys Stål, brown marmorated stink bug or BMSB, is now present in 43 US states. A native of eastern Asia, this pest can feed on ~200 different plant species damaging bark, leaves, buds, stems, ...

  Citation × Citation Citation Abstract Copy Title: Nutrient Profile and Nursery Feeding Damage of Halyomorpha halys (Hempitera: Pentatomidae) Author: Skillman, Victoria P. Halyomorpha halys Stål, brown marmorated stink bug or BMSB, is now present in 43 US states. A native of eastern Asia, this pest can feed on ~200 different plant species damaging bark, leaves, buds, stems, and fruits. Many of these plant species include wild plants, ornamentals, and agricultural crops. BMSB has become a major pest for growers in different cropping systems from orchard to row crops. They are also a major nuisance for homeowners because they overwinter in high numbers in human structures, where they annoy occupants and can cause other problems. Currently, much research has focused on the control and biology of BMSB. This thesis focuses on areas of BMSB biology where there are substantial knowledge gaps: the nutritional ecology of wild BMSB, nutrient content of BMSB eggs, and how BMSB feeding affects nursery crop growth. Understanding of the nutritional profile of wild BMSB over the season can help us understand how BMSB behavior is driven by nutritional needs and can indicate periods when pest is nutrient-limited and potentially more susceptible to management. In Chapter 2, lipid, glycogen and sugar levels of wild adult BMSB populations were measured in the Willamette Valley of Oregon as they emerged from overwintering boxes from March through June and throughout the summer season from May to September. Emerging adults had lower nutrient levels than overwintering adults that remained in the shelter suggesting that nutrient limitation may drive adults to leave overwintering sites. Also, nutrient levels of emerging adults steadily declined over the months that they emerged. In the summer, nutrient levels of adults collected from holly host plants fluctuated, and a dip in nutrient levels was observed as the new generation of adults became abundant. In Chapter 3, the nutrient content of BMSB eggs were measured to describe what resources are provided to the progeny and to the natural enemies that feed on or develop within eggs. Also, various fresh and frozen egg masses are used for biological control studies, and nutrient comparisons were made between various egg masses to assess quality. BMSB eggs followed adult nutrient trends by having higher lipid levels compared to sugar and glycogen. Eggs did not vary in nutrient levels over the lifespan of the female suggesting that when supplied a consistent diet, females allocate a consistent amount of nutrient to their eggs as they age. Wild and colony egg clusters varied in lipid and sugar levels. The color change and age of the egg clusters did not influence the nutrient levels. The deployment length caused eggs to decrease in sugar and glycogen levels, however, temperature and deployment*temperature combinations did not. Eggs that were frozen at -80°C for 1-2 years were associated with declining lipid levels and increasing sugar levels. While BMSB has been reported to damage nursery crops, and especially fruit, their impact on plant growth has not been quantified. Experiments represented in Chapter 4 evaluated BMSB feeding damage to nursery plants by caging adults on established stock block trees in the field and young potted seedlings in the greenhouse. The impact appeared limited; the established trees and young seedlings mostly grew at similar rates to control plants. In addition to these three topics, four additional nutrient profiles studies and two studies on biological control are included in the Appendices. Baseline information on the nutrient levels of the general adult population of BMSB in Oregon (A.1), BMSB nymphs (A.3), and native stink bugs of Oregon (A.4) are provided. Nutrient comparisons in May-June revealed that BMSB collected from the host plant of holly had substantially higher nutrient reserves than BMSB just exiting overwintering (A.2). Methyl salicylate lures were tested in a nursery and found to have no significant effect on egg predation or parasitism (A.5). A commercially available entomopathogenic fungus was sprayed directly on BMSB nymphs; it induced 26% greater mortality than the controls over a 12-day period. Title: Nutrient Profile and Nursery Feeding Damage of Halyomorpha halys (Hempitera: Pentatomidae) Author: Skillman, Victoria P. Halyomorpha halys Stål, brown marmorated stink bug or BMSB, is now present in 43 US states. A native of eastern Asia, this pest can feed on ~200 different plant species damaging bark, leaves, buds, stems, and fruits. Many of these plant species include wild plants, ornamentals, and agricultural crops. BMSB has become a major pest for growers in different cropping systems from orchard to row crops. They are also a major nuisance for homeowners because they overwinter in high numbers in human structures, where they annoy occupants and can cause other problems. Currently, much research has focused on the control and biology of BMSB. This thesis focuses on areas of BMSB biology where there are substantial knowledge gaps: the nutritional ecology of wild BMSB, nutrient content of BMSB eggs, and how BMSB feeding affects nursery crop growth. Understanding of the nutritional profile of wild BMSB over the season can help us understand how BMSB behavior is driven by nutritional needs and can indicate periods when pest is nutrient-limited and potentially more susceptible to management. In Chapter 2, lipid, glycogen and sugar levels of wild adult BMSB populations were measured in the Willamette Valley of Oregon as they emerged from overwintering boxes from March through June and throughout the summer season from May to September. Emerging adults had lower nutrient levels than overwintering adults that remained in the shelter suggesting that nutrient limitation may drive adults to leave overwintering sites. Also, nutrient levels of emerging adults steadily declined over the months that they emerged. In the summer, nutrient levels of adults collected from holly host plants fluctuated, and a dip in nutrient levels was observed as the new generation of adults became abundant. In Chapter 3, the nutrient content of BMSB eggs were measured to describe what resources are provided to the progeny and to the natural enemies that feed on or develop within eggs. Also, various fresh and frozen egg masses are used for biological control studies, and nutrient comparisons were made between various egg masses to assess quality. BMSB eggs followed adult nutrient trends by having higher lipid levels compared to sugar and glycogen. Eggs did not vary in nutrient levels over the lifespan of the female suggesting that when supplied a consistent diet, females allocate a consistent amount of nutrient to their eggs as they age. Wild and colony egg clusters varied in lipid and sugar levels. The color change and age of the egg clusters did not influence the nutrient levels. The deployment length caused eggs to decrease in sugar and glycogen levels, however, temperature and deployment*temperature combinations did not. Eggs that were frozen at -80°C for 1-2 years were associated with declining lipid levels and increasing sugar levels. While BMSB has been reported to damage nursery crops, and especially fruit, their impact on plant growth has not been quantified. Experiments represented in Chapter 4 evaluated BMSB feeding damage to nursery plants by caging adults on established stock block trees in the field and young potted seedlings in the greenhouse. The impact appeared limited; the established trees and young seedlings mostly grew at similar rates to control plants. In addition to these three topics, four additional nutrient profiles studies and two studies on biological control are included in the Appendices. Baseline information on the nutrient levels of the general adult population of BMSB in Oregon (A.1), BMSB nymphs (A.3), and native stink bugs of Oregon (A.4) are provided. Nutrient comparisons in May-June revealed that BMSB collected from the host plant of holly had substantially higher nutrient reserves than BMSB just exiting overwintering (A.2). Methyl salicylate lures were tested in a nursery and found to have no significant effect on egg predation or parasitism (A.5). A commercially available entomopathogenic fungus was sprayed directly on BMSB nymphs; it induced 26% greater mortality than the controls over a 12-day period. Close

• 31. [Article] Performance of Willamette Valley native plants following herbicide exposure

  Prairies were once the dominant vegetation type in Oregon's Willamette Valley. Land use conversion, fire suppression, succession, and invasive species have reduced Willamette Valley prairies to less than ...

  Citation × Citation Citation Abstract Copy Title: Performance of Willamette Valley native plants following herbicide exposure Author: Blakeley-Smith, Matthew R. Prairies were once the dominant vegetation type in Oregon's Willamette Valley. Land use conversion, fire suppression, succession, and invasive species have reduced Willamette Valley prairies to less than 1% of their historical area. The remnant prairies that persist today are small in size and are highly fragmented. Marginal strips of habitat along roadsides and agricultural fields play an important role as refugia for native species and provide important resources for wildlife. These seemingly insignificant habitat units may also play an important role in facilitating gene flow between disjunct populations of prairie plants, thus reducing the potential for the negative effects of inbreeding depression. Presently, much of the land area in the Willamette Valley is dedicated to commercial agricultural which is heavily reliant on herbicides for weed control and field preparation. Since herbicide applications are imprecise and prone to drift, there is potential to impact the native plants surrounding these agricultural fields. Current EPA methods for assessing the ecological effects of herbicides may not be robust enough to account for potential impacts on native plants since the suggested test species are ten annual agricultural crops. To address the need for improved phytotoxicity testing protocols, we incorporated non-crop plant species into the EPA vegetative vigor test methodology for use in determining effects of low concentrations of chemical herbicides on Willamette Valley terrestrial plants. A separate experiment was conducted in order to determine how herbicides might be used to restore Butterfly Meadows, a degraded Willamette Valley prairie. The specific objective of this study were to: 1.) determine which herbicide treatments were most effective at reducing dominance of an invasive species, Brachypodium sylvaticum, 2.) determine if native species declined following herbicide treatments, and 3.) describe the compositional changes in the plant communities over a four-year period. The EPA vegetative vigor test study showed that there was a wide variety of responses among 17 species (14 native and 3 introduced) to each herbicide tested (glyphosate, tribenuron, and fluazifop). For glyphosate, Potentilla gracilis was the most sensitive species based on an EC25 value of 0.012 x f.a.r. for dry weight; while Bromus carinatus, Clarkia amoena, Gilia capitata, and Lupinus albicaulis were tolerant to glyphosate as indicated by no effect on dry weight. Seven Willamette Valley forb species were sensitive to tribenuron based on EC25 values ranging from 0.001 to 0.012 x f.a.r.; Clarkia amoena, Collinsia grandflora, Leucanthemum vulgare, Potentilla gracilis, Prunella vulgaris, Ranunculus occidentalis and Sanquisorba occidentalis. Six grass species and Eriophyllum lanatum were resistant to tribenuron showing no reduction in dry weight. Fluazifop primarily affected grass species as expected due to the grass-specific activity for this herbicide. Two native grasses, Elymus trachycaulus and Danthonia californica were the most sensitive to fluazifop, based on low EC25 values of 0.002 to 0.010 x f.a.r. A native fescue grass, Festuca roemeri, and nearly all the forb species were resistant to fluazifop, showing no response at any herbicide rate applied. The results from this research will be useful as background information for evaluating potential modifications in the EPA's Vegetative Vigor Test to assess the risk of herbicides to non-target plants. Seven different herbicide combinations were effective at reducing the cover of Brachypodium sylvaticum in test plots at Butterfly Meadows one year after treatment. The reduction of B. sylvaticum was short lived however, since the cover of this grass species was not different from control plots during the second growing season. Native plant species were not negatively impacted by the herbicide treatments, as shown by MRPP analysis. Successional trajectories illustrate that control plots that were dominated by B. sylvaticum remained relatively unchanged over the course of four years. Some treatments exhibited a sharp decline in dominance by graminoids after the first year, a recovery the second year, but never returned exactly to their pretreatment community composition after the third year. The reduction of the dominant species after the first growing season was associated with colonization by a number of introduced species into the newly created open habitat. Over the same period there was no overall increase in native species cover, suggesting that the native species at this site may be recruitment limited. Future restoration activities at this site should include multiple years of B. sylvaticum control, with special attention to the seed bank and tolerant individuals. Seed additions of native species may help fill empty niches and afford resistance to invasion by introduced species. Title: Performance of Willamette Valley native plants following herbicide exposure Author: Blakeley-Smith, Matthew R. Prairies were once the dominant vegetation type in Oregon's Willamette Valley. Land use conversion, fire suppression, succession, and invasive species have reduced Willamette Valley prairies to less than 1% of their historical area. The remnant prairies that persist today are small in size and are highly fragmented. Marginal strips of habitat along roadsides and agricultural fields play an important role as refugia for native species and provide important resources for wildlife. These seemingly insignificant habitat units may also play an important role in facilitating gene flow between disjunct populations of prairie plants, thus reducing the potential for the negative effects of inbreeding depression. Presently, much of the land area in the Willamette Valley is dedicated to commercial agricultural which is heavily reliant on herbicides for weed control and field preparation. Since herbicide applications are imprecise and prone to drift, there is potential to impact the native plants surrounding these agricultural fields. Current EPA methods for assessing the ecological effects of herbicides may not be robust enough to account for potential impacts on native plants since the suggested test species are ten annual agricultural crops. To address the need for improved phytotoxicity testing protocols, we incorporated non-crop plant species into the EPA vegetative vigor test methodology for use in determining effects of low concentrations of chemical herbicides on Willamette Valley terrestrial plants. A separate experiment was conducted in order to determine how herbicides might be used to restore Butterfly Meadows, a degraded Willamette Valley prairie. The specific objective of this study were to: 1.) determine which herbicide treatments were most effective at reducing dominance of an invasive species, Brachypodium sylvaticum, 2.) determine if native species declined following herbicide treatments, and 3.) describe the compositional changes in the plant communities over a four-year period. The EPA vegetative vigor test study showed that there was a wide variety of responses among 17 species (14 native and 3 introduced) to each herbicide tested (glyphosate, tribenuron, and fluazifop). For glyphosate, Potentilla gracilis was the most sensitive species based on an EC25 value of 0.012 x f.a.r. for dry weight; while Bromus carinatus, Clarkia amoena, Gilia capitata, and Lupinus albicaulis were tolerant to glyphosate as indicated by no effect on dry weight. Seven Willamette Valley forb species were sensitive to tribenuron based on EC25 values ranging from 0.001 to 0.012 x f.a.r.; Clarkia amoena, Collinsia grandflora, Leucanthemum vulgare, Potentilla gracilis, Prunella vulgaris, Ranunculus occidentalis and Sanquisorba occidentalis. Six grass species and Eriophyllum lanatum were resistant to tribenuron showing no reduction in dry weight. Fluazifop primarily affected grass species as expected due to the grass-specific activity for this herbicide. Two native grasses, Elymus trachycaulus and Danthonia californica were the most sensitive to fluazifop, based on low EC25 values of 0.002 to 0.010 x f.a.r. A native fescue grass, Festuca roemeri, and nearly all the forb species were resistant to fluazifop, showing no response at any herbicide rate applied. The results from this research will be useful as background information for evaluating potential modifications in the EPA's Vegetative Vigor Test to assess the risk of herbicides to non-target plants. Seven different herbicide combinations were effective at reducing the cover of Brachypodium sylvaticum in test plots at Butterfly Meadows one year after treatment. The reduction of B. sylvaticum was short lived however, since the cover of this grass species was not different from control plots during the second growing season. Native plant species were not negatively impacted by the herbicide treatments, as shown by MRPP analysis. Successional trajectories illustrate that control plots that were dominated by B. sylvaticum remained relatively unchanged over the course of four years. Some treatments exhibited a sharp decline in dominance by graminoids after the first year, a recovery the second year, but never returned exactly to their pretreatment community composition after the third year. The reduction of the dominant species after the first growing season was associated with colonization by a number of introduced species into the newly created open habitat. Over the same period there was no overall increase in native species cover, suggesting that the native species at this site may be recruitment limited. Future restoration activities at this site should include multiple years of B. sylvaticum control, with special attention to the seed bank and tolerant individuals. Seed additions of native species may help fill empty niches and afford resistance to invasion by introduced species. Close

• 32. [Article] The development and analysis of future agricultural landscapes

  Alternative futures studies provide a way for policy-makers and stakeholders to investigate the future impacts of different management strategies by providing representations of possible outcomes. An alternative ...

  Citation × Citation Citation Abstract Copy Title: The development and analysis of future agricultural landscapes Author: Berger, Patricia A. Alternative futures studies provide a way for policy-makers and stakeholders to investigate the future impacts of different management strategies by providing representations of possible outcomes. An alternative futures study was undertaken by the Pacific Northwest-Ecosystem Research Consortium for the Willamette River Basin, Oregon, USA, to determine how this regional system would respond to various drivers of change. To support this effort required the development of a simulation model that generates future agricultural landscapes in response to these drivers of change and the evaluation of the resulting landscapes to derive information useful for policy analysis and community discussions. These goals were achieved by creating a characterization of the initial agricultural system, developing an agricultural land-cover change model, and finally, integrating this model with scenario elements to produce the final agricultural landscape evolution model. An important part of the initial landscape characterization was determining the crop suitability class of the basin's agricultural soils for 14 commonly grown crops. Suitability rankings were generated by using rough-set rule induction to create predictive if-then rules that related a soil's biophysical characteristics to crop production and then applying these rules to all the agricultural soils in the basin. After characterizing the agricultural system, a spatially explicit, multi-attribute decision model was developed to simulate a grower's crop-selection decision. This model used attributes describing a field's biophysical conditions and each crop's agronomic, economic, and management characteristics to select a field's preferred crop from a list of crop alternatives. Next, rules and constraints were formulated for each of the three policy scenarios: a continuation of current trends, an increased reliance on market forces to determine land use, and an increased emphasis on environmental restoration programs. The initial agricultural landscape depiction, crop selection model, and scenario rules were used to generate three future landscapes, each depicting an alternative state of the agricultural system in the year 2050. Then, landscape metrics and screening models were used to assess the agronomic and environmental condition of each agricultural landscape. Finally, this information was placed into the context of the Willamette River Basin, with suggestions for policy development and analysis. Title: The development and analysis of future agricultural landscapes Author: Berger, Patricia A. Alternative futures studies provide a way for policy-makers and stakeholders to investigate the future impacts of different management strategies by providing representations of possible outcomes. An alternative futures study was undertaken by the Pacific Northwest-Ecosystem Research Consortium for the Willamette River Basin, Oregon, USA, to determine how this regional system would respond to various drivers of change. To support this effort required the development of a simulation model that generates future agricultural landscapes in response to these drivers of change and the evaluation of the resulting landscapes to derive information useful for policy analysis and community discussions. These goals were achieved by creating a characterization of the initial agricultural system, developing an agricultural land-cover change model, and finally, integrating this model with scenario elements to produce the final agricultural landscape evolution model. An important part of the initial landscape characterization was determining the crop suitability class of the basin's agricultural soils for 14 commonly grown crops. Suitability rankings were generated by using rough-set rule induction to create predictive if-then rules that related a soil's biophysical characteristics to crop production and then applying these rules to all the agricultural soils in the basin. After characterizing the agricultural system, a spatially explicit, multi-attribute decision model was developed to simulate a grower's crop-selection decision. This model used attributes describing a field's biophysical conditions and each crop's agronomic, economic, and management characteristics to select a field's preferred crop from a list of crop alternatives. Next, rules and constraints were formulated for each of the three policy scenarios: a continuation of current trends, an increased reliance on market forces to determine land use, and an increased emphasis on environmental restoration programs. The initial agricultural landscape depiction, crop selection model, and scenario rules were used to generate three future landscapes, each depicting an alternative state of the agricultural system in the year 2050. Then, landscape metrics and screening models were used to assess the agronomic and environmental condition of each agricultural landscape. Finally, this information was placed into the context of the Willamette River Basin, with suggestions for policy development and analysis. Close

• 33. [Article] Soil-diffusive gradient in thin films partition coefficients estimate metal bioavailability to crops at fertilized field sites

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Society of Environmental Toxicology and Chemistry and can be found at: http...

  Citation × Citation Citation Abstract Copy Title: Soil-diffusive gradient in thin films partition coefficients estimate metal bioavailability to crops at fertilized field sites Author: Anderson, Kim A., Pérez, Angela L. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Society of Environmental Toxicology and Chemistry and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291552-8618. Title: Soil-diffusive gradient in thin films partition coefficients estimate metal bioavailability to crops at fertilized field sites Author: Anderson, Kim A., Pérez, Angela L. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Society of Environmental Toxicology and Chemistry and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291552-8618. Close

• 34. [Article] Profit Sharing in Renewable Resource industries: Implications and Optimal Management

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Profit Sharing in Renewable Resource industries: Implications and Optimal Management Author: LaRiviere, Jacob Abstract only. Title: Profit Sharing in Renewable Resource industries: Implications and Optimal Management Author: LaRiviere, Jacob Abstract only. Close

• 35. [Article] Returning grain to the lower-Willamette Valley : prospects and barriers for local food security

  A critical link is missing between food production and food consumption. This gap can be overcome by encouraging the production of staple food crops and emphasizing regional and community consumption of ...

  Citation × Citation Citation Abstract Copy Title: Returning grain to the lower-Willamette Valley : prospects and barriers for local food security Author: Malone, Chevelle P. A critical link is missing between food production and food consumption. This gap can be overcome by encouraging the production of staple food crops and emphasizing regional and community consumption of locally produced food. In order to re-establish local food security in the Willamette Valley, it is imperative that essential infrastructure be re-established in support of local food production and processing. To increase local food security, production of food crops within agricultural communities must increase, and grain infrastructure must be built to efficiently process locally grown grain. Using the case of the lower-Willamette Valley, this research seeks to answer three questions: 1) how has the agricultural history of grain crops and grass-seed in the lower-Willamette Valley changed since the European immigration, and does this history support a transition to grain crops; 2) what are the barriers to transitioning to grain crops in support of increased food security in this region; and 3) how does grain production, processing and infrastructure fit into the region's long-term food security and sustainability goals. These questions are answered by conducting a literature review to reveal the rise and fall of both grain and grass-seed in the region, and additionally using remotely sensed images to visually expound on the changed agricultural landscape of the lower-Willamette Valley for three consecutive decades. Interviews and focus groups with regional grass-seed and grain farmers illuminate numerous barriers to transitioning to grain crops. Lack of grain infrastructure was noted as a major barrier to increasing food security through local food production. In order to illustrate the connection between grain infrastructure and food security, ArcGIS is used to map out grain infrastructure within the study area. Lastly, the imagery of the changing landscape and the grain infrastructure map are examined in conjunction with community food security and sustainability goals in the cities of Eugene and Corvallis, Oregon to assist these communities in reaching their food security and sustainability goals. This research determines that re-energizing the Willamette Valley grain-market by way of the local food security and community sustainability efforts is only effective if done collaboratively between farmers, local businesses, city and county leadership and the community because of the innate difference between the national-international market where grass-seed is prevalent and the local-regional market of grain. Title: Returning grain to the lower-Willamette Valley : prospects and barriers for local food security Author: Malone, Chevelle P. A critical link is missing between food production and food consumption. This gap can be overcome by encouraging the production of staple food crops and emphasizing regional and community consumption of locally produced food. In order to re-establish local food security in the Willamette Valley, it is imperative that essential infrastructure be re-established in support of local food production and processing. To increase local food security, production of food crops within agricultural communities must increase, and grain infrastructure must be built to efficiently process locally grown grain. Using the case of the lower-Willamette Valley, this research seeks to answer three questions: 1) how has the agricultural history of grain crops and grass-seed in the lower-Willamette Valley changed since the European immigration, and does this history support a transition to grain crops; 2) what are the barriers to transitioning to grain crops in support of increased food security in this region; and 3) how does grain production, processing and infrastructure fit into the region's long-term food security and sustainability goals. These questions are answered by conducting a literature review to reveal the rise and fall of both grain and grass-seed in the region, and additionally using remotely sensed images to visually expound on the changed agricultural landscape of the lower-Willamette Valley for three consecutive decades. Interviews and focus groups with regional grass-seed and grain farmers illuminate numerous barriers to transitioning to grain crops. Lack of grain infrastructure was noted as a major barrier to increasing food security through local food production. In order to illustrate the connection between grain infrastructure and food security, ArcGIS is used to map out grain infrastructure within the study area. Lastly, the imagery of the changing landscape and the grain infrastructure map are examined in conjunction with community food security and sustainability goals in the cities of Eugene and Corvallis, Oregon to assist these communities in reaching their food security and sustainability goals. This research determines that re-energizing the Willamette Valley grain-market by way of the local food security and community sustainability efforts is only effective if done collaboratively between farmers, local businesses, city and county leadership and the community because of the innate difference between the national-international market where grass-seed is prevalent and the local-regional market of grain. Close

• 36. [Article] The Primary Disease Gradient of Wheat Stripe Rust (Puccinia striiformis f. sp. tritici) Across Spatial Scales

  Wheat stripe rust (WSR), also called yellow rust of wheat (Tricitum spp.), causal agent Puccinia striiformis f.sp. tritici (Pst), is a foliar disease of major economic importance on wheat, especially grown ...

  Citation × Citation Citation Abstract Copy Title: The Primary Disease Gradient of Wheat Stripe Rust (Puccinia striiformis f. sp. tritici) Across Spatial Scales Author: Farber, Daniel Wheat stripe rust (WSR), also called yellow rust of wheat (Tricitum spp.), causal agent Puccinia striiformis f.sp. tritici (Pst), is a foliar disease of major economic importance on wheat, especially grown in temperate locations. WSR causes major losses of wheat yield, estimated at nearly $ 1 billion per year, and has been found in upwards of sixty countries throughout the world, particularly in temperate regions. WSR, like many diseases of widely planted agricultural crops, has been managed largely by breeding resistant cultivars of wheat and by applying fungicide, but these strategies have resulted in periodic intensifications of WSR epidemics due to Pst mutations overcoming resistance or becoming resistant to fungicides. However, these strategies can be augmented to control WSR and other plant diseases by understanding the epidemiology, including the dispersal patterns of their causal pathogens, factors affecting the pathogen’s infection efficiency and reproduction rate, allowing managers to make better informed decisions. In this dissertation, I have examined the spread of WSR, bridging theoretical dispersal and disease ecology with plant epidemiology to provide analyses that have direct applicability to managing the spread of diseases caused by foliar wind-dispersed plant pathogens, as well as increase our understanding of basic biological processes. To investigate the dispersal gradient of Pst, I inoculated single wheat leaves with Pst urediniospores, and sampled all wheat leaves within two intersecting 0.3 m × 3.0 m transects in eight replicates over three years. The lesions observed on each of the top three leaves on plants within 1.5 m from the source lesion were three-dimensionally mapped. The total number of lesions within a 1.5 m radius was estimated by dividing the number of lesions observed within each 0.025 m-wide annulus by the fraction of the annulus sampled. The estimated total number of lesions produced within 1.5 m of a single source lesion ranged from 27 to 776 with a mean of 288 lesions. Eighty percent of the lesions were recorded within 0.69 m of the source infection. The proportion of total lesions observed at a given distance from the source was fit well by the Lomax and Weibull distributions, reflecting the large proportion of lesions arising close to the source, and when fit to a modified inverse-power distribution had a slope (b) of 2.5. There were more lesions produced on leaves higher in the canopy than on lower leaves, with more lesions being detected above than below the point of inoculation. Simultaneous measurement of lesion gradients and spore dispersal in the final year of the study suggests that this pattern is owing to greater susceptibility of upper leaves, rather than increased dispersal to upper leaves. In addition to dispersal of pathogen propagules, disease spread requires successful infection of host tissue. In plant disease epidemiology, susceptibility of host tissue is often assumed to be constant. This assumption ignores changes in host phenology due to developmental stage. To examine relative susceptibility of wheat leaves of different ages and leaf positions, 3-, 4-, and 5- wk old wheat plants were inoculated with equal quantities of urediniospores of Puccinia striiformis f.sp. tritici, the causal agent of wheat stripe rust (WSR). Disease severity on each leaf was assessed and fit by mixed effect linear model as function of leaf position and plant age. Younger plants had significantly greater disease severity than older plants, with mean severities of 50.4%, 30.1%, and 12.9% on plants that were 3 wk, 4 wk, and 5 wk old at time of inoculation, respectively. This effect was greater on leaves higher on the plant. Within same-aged plants, younger leaves had significantly greater disease severity than older leaves, with mean severities of 40.2%, 34.8%, and 17.7% on the uppermost, second, and third leaf, respectively. These results corroborate field data suggesting the vertical distribution of lesions was due more to differences in host susceptibility than to propagule dispersal. The results of the primary dispersal gradient of Pst study were contextualized with previous studies of dispersal of cereal rusts by investigating their dispersal across spatial scales. This was accomplished by combining the local dispersal dataset with a previous Pst dispersal dataset across agricultural fields out to 91.4 m. These datasets were normalized by the mean number of infections observed per plant at 0.914 m from the center of the disease focus after a single generation of spread. These datasets were well-fit by a single modified inverse power function, ?=1.17∗(?+0.10 ?)⁻²·²⁴. This function was then used to combine the local and fieldwide datasets with a primary dispersal dataset of Puccinia graminis f.sp. tritici (Pgt) out to 10.62 km, by predicting the number of lesions per plant at 2730 m from the disease source, to which all observations in the Pgt regional dataset were normalized, which was well fit by ?=1.26∗(?+0.14 ?)⁻²·³⁹. I created a susceptible-latent-infectious-removed (SLIR) compartmental time-step model to assess disease spread over time across spatial scales. The modified inverse-power function fit to the combined dispersal data across all three spatial scales was used to seed the dispersal kernel, comparing epidemics stemming from initial foci of 1.52 m with compartment sizes of 1.52 m and 0.025 m, and comparing epidemics stemming from initial foci of 152 m with compartments size of 152 m and 1.52 m. The resulting models produced very similar disease levels, as quantified by taking the area under the dispersal curve after seven generations of spread. In this dissertation, I have examined the spread Pst, as a model system to better understand the spread of diseases caused by aerially-dispersed pathogens. This research will do much to fill in gaps in the literature on empirical measures of pathogen dispersal and infection, and the theoretical ramifications of modelling disease spread incorporating multiple spatial scales. It is the aim of this research to be applicable to a wide range of systems exhibiting similar attributes, particularly in regards to dispersal, in addition to aiding our understanding of Pst and other cereal rusts. Title: The Primary Disease Gradient of Wheat Stripe Rust (Puccinia striiformis f. sp. tritici) Across Spatial Scales Author: Farber, Daniel Wheat stripe rust (WSR), also called yellow rust of wheat (Tricitum spp.), causal agent Puccinia striiformis f.sp. tritici (Pst), is a foliar disease of major economic importance on wheat, especially grown in temperate locations. WSR causes major losses of wheat yield, estimated at nearly $ 1 billion per year, and has been found in upwards of sixty countries throughout the world, particularly in temperate regions. WSR, like many diseases of widely planted agricultural crops, has been managed largely by breeding resistant cultivars of wheat and by applying fungicide, but these strategies have resulted in periodic intensifications of WSR epidemics due to Pst mutations overcoming resistance or becoming resistant to fungicides. However, these strategies can be augmented to control WSR and other plant diseases by understanding the epidemiology, including the dispersal patterns of their causal pathogens, factors affecting the pathogen’s infection efficiency and reproduction rate, allowing managers to make better informed decisions. In this dissertation, I have examined the spread of WSR, bridging theoretical dispersal and disease ecology with plant epidemiology to provide analyses that have direct applicability to managing the spread of diseases caused by foliar wind-dispersed plant pathogens, as well as increase our understanding of basic biological processes. To investigate the dispersal gradient of Pst, I inoculated single wheat leaves with Pst urediniospores, and sampled all wheat leaves within two intersecting 0.3 m × 3.0 m transects in eight replicates over three years. The lesions observed on each of the top three leaves on plants within 1.5 m from the source lesion were three-dimensionally mapped. The total number of lesions within a 1.5 m radius was estimated by dividing the number of lesions observed within each 0.025 m-wide annulus by the fraction of the annulus sampled. The estimated total number of lesions produced within 1.5 m of a single source lesion ranged from 27 to 776 with a mean of 288 lesions. Eighty percent of the lesions were recorded within 0.69 m of the source infection. The proportion of total lesions observed at a given distance from the source was fit well by the Lomax and Weibull distributions, reflecting the large proportion of lesions arising close to the source, and when fit to a modified inverse-power distribution had a slope (b) of 2.5. There were more lesions produced on leaves higher in the canopy than on lower leaves, with more lesions being detected above than below the point of inoculation. Simultaneous measurement of lesion gradients and spore dispersal in the final year of the study suggests that this pattern is owing to greater susceptibility of upper leaves, rather than increased dispersal to upper leaves. In addition to dispersal of pathogen propagules, disease spread requires successful infection of host tissue. In plant disease epidemiology, susceptibility of host tissue is often assumed to be constant. This assumption ignores changes in host phenology due to developmental stage. To examine relative susceptibility of wheat leaves of different ages and leaf positions, 3-, 4-, and 5- wk old wheat plants were inoculated with equal quantities of urediniospores of Puccinia striiformis f.sp. tritici, the causal agent of wheat stripe rust (WSR). Disease severity on each leaf was assessed and fit by mixed effect linear model as function of leaf position and plant age. Younger plants had significantly greater disease severity than older plants, with mean severities of 50.4%, 30.1%, and 12.9% on plants that were 3 wk, 4 wk, and 5 wk old at time of inoculation, respectively. This effect was greater on leaves higher on the plant. Within same-aged plants, younger leaves had significantly greater disease severity than older leaves, with mean severities of 40.2%, 34.8%, and 17.7% on the uppermost, second, and third leaf, respectively. These results corroborate field data suggesting the vertical distribution of lesions was due more to differences in host susceptibility than to propagule dispersal. The results of the primary dispersal gradient of Pst study were contextualized with previous studies of dispersal of cereal rusts by investigating their dispersal across spatial scales. This was accomplished by combining the local dispersal dataset with a previous Pst dispersal dataset across agricultural fields out to 91.4 m. These datasets were normalized by the mean number of infections observed per plant at 0.914 m from the center of the disease focus after a single generation of spread. These datasets were well-fit by a single modified inverse power function, ?=1.17∗(?+0.10 ?)⁻²·²⁴. This function was then used to combine the local and fieldwide datasets with a primary dispersal dataset of Puccinia graminis f.sp. tritici (Pgt) out to 10.62 km, by predicting the number of lesions per plant at 2730 m from the disease source, to which all observations in the Pgt regional dataset were normalized, which was well fit by ?=1.26∗(?+0.14 ?)⁻²·³⁹. I created a susceptible-latent-infectious-removed (SLIR) compartmental time-step model to assess disease spread over time across spatial scales. The modified inverse-power function fit to the combined dispersal data across all three spatial scales was used to seed the dispersal kernel, comparing epidemics stemming from initial foci of 1.52 m with compartment sizes of 1.52 m and 0.025 m, and comparing epidemics stemming from initial foci of 152 m with compartments size of 152 m and 1.52 m. The resulting models produced very similar disease levels, as quantified by taking the area under the dispersal curve after seven generations of spread. In this dissertation, I have examined the spread Pst, as a model system to better understand the spread of diseases caused by aerially-dispersed pathogens. This research will do much to fill in gaps in the literature on empirical measures of pathogen dispersal and infection, and the theoretical ramifications of modelling disease spread incorporating multiple spatial scales. It is the aim of this research to be applicable to a wide range of systems exhibiting similar attributes, particularly in regards to dispersal, in addition to aiding our understanding of Pst and other cereal rusts. Close

• 37. [Article] Brown Marmorated Stink Bug (BMSB), Halyomorpha halys Taint in Wine : Impact on Wine Sensory, Effect of Wine-processing and Management Techniques

  Brown marmorated stink bug (BMSB), (Halyomorpha halys, Hemiptera: Pentatomidae) is an invasive species that damages numerous agricultural crops including grapes. Related damage include lower ...

  Citation × Citation Citation Abstract Copy Title: Brown Marmorated Stink Bug (BMSB), Halyomorpha halys Taint in Wine : Impact on Wine Sensory, Effect of Wine-processing and Management Techniques Author: Mohekar, Pallavi, 1985- Brown marmorated stink bug (BMSB), (Halyomorpha halys, Hemiptera: Pentatomidae) is an invasive species that damages numerous agricultural crops including grapes. Related damage include lower berry weight with increased exposure and cracked berries as a result of BMSB feeding activity. The insect is currently detected in 43 US states including Oregon, Washington, California, and New York. The grape and wine industries in these areas hold significant economic value. BMSB damage has already resulted in major economic loss in the agricultural industry. Current data indicates that the infestation is spreading to new regions and its population density is increasing in regions where it has been detected. Surveys show BMSB in vineyards of Oregon, Virginia and New York where BMSB can damage grapes, lowering their yield and quality. When harvested with grape clusters, BMSB can introduce volatile compounds, trans-2-decenal and tridecane, into wine. Prior work has shown that the presence of these compounds alters wine sensory. In this thesis, the focus is on analyzing BMSB’s impact on wine quality and consumer preference. Additionally, this work determines the action threshold (AT) for BMSB in the vineyard, which is likely to prove important to the grape and wine industry in designing control limits and maintaining wine quality. The first contribution of this work establishes the sensory detection threshold (DT) and consumer rejection thresholds (CRT) for trans-2-decenal in red wine. Trans-2-decenal is one of the main aroma compounds in BMSB taint, having green, cilantro-like aroma characteristics that is undesirable in wine. Results conclusively show that trans-2-decenal in wine has a negative effect on its quality. In Pinot noir, consumers were able to perceive trans-2-decenal at 1.92 µg/L (DT). Consumer preference for Pinot noir and Merlot containing trans-2-decenal decreased significantly above the concentration of 4.8 µg/L (CRT). Pinot noir containing trans-2-decenal above CRT was described as green, herbal, musty and less fruity by wine professionals. Based on such findings, the use of CRT is recommended when establishing consumer tolerance levels of trans-2-decenal in wine. The second contribution relates BMSB presence in vineyard with sensory threshold of trans-2-decenal in the finished wine. Pinot noir, Merlot and Pinot gris were produced using different densities of BMSB in grape clusters. The results of this study indicate BMSB density of three per cluster can result in Pinot noir containing trans-2-decenal at its DT and below its CRT. This density can be used as AT for BMSB in the vineyard since wines made from grapes contaminated at or greater than 3 BMSB per cluster are likely to experience low preference by wine consumers. The same BMSB density can be used to devise control measures for Merlot since trans-2-decenal CRT was found to be similar for both Pinot noir and Merlot. Pinot gris was found to be free of trans-2-decenal even at BMSB density of 1 per cluster. Therefore, we believe that BMSB may not be a concern for white wines. The third contribution provides methods to reduce BMSB taint in finished wine. This can be done by modifying the winemaking process or by applying corrective measures in the wine. During winemaking, destemming and pressing were identified to be the steps responsible for increasing BMSB taint levels in wine whereas alcoholic fermentation decreases taint levels. Consequently, finished white wine was found to be free of trans-2-decenal since fermentation occurs after pressing. However, trans-2-decenal was present in finished red wine since pressing occurs after fermentation. Taint levels in finished red wine are also affected by different pressing variants (free run versus press fraction, bladder press versus basket press), with press fraction and bladder press introducing more BMSB taint compared to free run and basket press. This information will allow winemakers to adjust processing steps in order to minimize BMSB taint levels in red wines. Further reduction in taint levels was shown to be possible through the use of reverse osmosis filtration. Alternatively, oak addition can be used to mask the sensory attributes of trans-2-decenal at the risk of introducing spicy notes into wine. None of the other common fining agents tested were found to be effective against trans-2-decenal. Taken together, this thesis contributes a number of novel insights into the impact of BMSB on red and white wine. By relating consumer thresholds and descriptive analysis with chemical and wine processing, we are able to establish control densities for the pest in the vineyard, identify key processing steps and post-fermentation treatments to reduce BMSB taint. The information contained in this thesis is likely to prove valuable to the wine industry in its struggle against BMSB. Title: Brown Marmorated Stink Bug (BMSB), Halyomorpha halys Taint in Wine : Impact on Wine Sensory, Effect of Wine-processing and Management Techniques Author: Mohekar, Pallavi, 1985- Brown marmorated stink bug (BMSB), (Halyomorpha halys, Hemiptera: Pentatomidae) is an invasive species that damages numerous agricultural crops including grapes. Related damage include lower berry weight with increased exposure and cracked berries as a result of BMSB feeding activity. The insect is currently detected in 43 US states including Oregon, Washington, California, and New York. The grape and wine industries in these areas hold significant economic value. BMSB damage has already resulted in major economic loss in the agricultural industry. Current data indicates that the infestation is spreading to new regions and its population density is increasing in regions where it has been detected. Surveys show BMSB in vineyards of Oregon, Virginia and New York where BMSB can damage grapes, lowering their yield and quality. When harvested with grape clusters, BMSB can introduce volatile compounds, trans-2-decenal and tridecane, into wine. Prior work has shown that the presence of these compounds alters wine sensory. In this thesis, the focus is on analyzing BMSB’s impact on wine quality and consumer preference. Additionally, this work determines the action threshold (AT) for BMSB in the vineyard, which is likely to prove important to the grape and wine industry in designing control limits and maintaining wine quality. The first contribution of this work establishes the sensory detection threshold (DT) and consumer rejection thresholds (CRT) for trans-2-decenal in red wine. Trans-2-decenal is one of the main aroma compounds in BMSB taint, having green, cilantro-like aroma characteristics that is undesirable in wine. Results conclusively show that trans-2-decenal in wine has a negative effect on its quality. In Pinot noir, consumers were able to perceive trans-2-decenal at 1.92 µg/L (DT). Consumer preference for Pinot noir and Merlot containing trans-2-decenal decreased significantly above the concentration of 4.8 µg/L (CRT). Pinot noir containing trans-2-decenal above CRT was described as green, herbal, musty and less fruity by wine professionals. Based on such findings, the use of CRT is recommended when establishing consumer tolerance levels of trans-2-decenal in wine. The second contribution relates BMSB presence in vineyard with sensory threshold of trans-2-decenal in the finished wine. Pinot noir, Merlot and Pinot gris were produced using different densities of BMSB in grape clusters. The results of this study indicate BMSB density of three per cluster can result in Pinot noir containing trans-2-decenal at its DT and below its CRT. This density can be used as AT for BMSB in the vineyard since wines made from grapes contaminated at or greater than 3 BMSB per cluster are likely to experience low preference by wine consumers. The same BMSB density can be used to devise control measures for Merlot since trans-2-decenal CRT was found to be similar for both Pinot noir and Merlot. Pinot gris was found to be free of trans-2-decenal even at BMSB density of 1 per cluster. Therefore, we believe that BMSB may not be a concern for white wines. The third contribution provides methods to reduce BMSB taint in finished wine. This can be done by modifying the winemaking process or by applying corrective measures in the wine. During winemaking, destemming and pressing were identified to be the steps responsible for increasing BMSB taint levels in wine whereas alcoholic fermentation decreases taint levels. Consequently, finished white wine was found to be free of trans-2-decenal since fermentation occurs after pressing. However, trans-2-decenal was present in finished red wine since pressing occurs after fermentation. Taint levels in finished red wine are also affected by different pressing variants (free run versus press fraction, bladder press versus basket press), with press fraction and bladder press introducing more BMSB taint compared to free run and basket press. This information will allow winemakers to adjust processing steps in order to minimize BMSB taint levels in red wines. Further reduction in taint levels was shown to be possible through the use of reverse osmosis filtration. Alternatively, oak addition can be used to mask the sensory attributes of trans-2-decenal at the risk of introducing spicy notes into wine. None of the other common fining agents tested were found to be effective against trans-2-decenal. Taken together, this thesis contributes a number of novel insights into the impact of BMSB on red and white wine. By relating consumer thresholds and descriptive analysis with chemical and wine processing, we are able to establish control densities for the pest in the vineyard, identify key processing steps and post-fermentation treatments to reduce BMSB taint. The information contained in this thesis is likely to prove valuable to the wine industry in its struggle against BMSB. Close

• 38. [Article] Constraints and financial profitability to the exploitation of natural

  Research Paper

  Citation × Citation Citation Abstract Copy Title: Constraints and financial profitability to the exploitation of natural Author: Meke Soung, Pierre Nolasque Research Paper Title: Constraints and financial profitability to the exploitation of natural Author: Meke Soung, Pierre Nolasque Research Paper Close

• 39. [Article] The Agricultural Model Intercomparison and Improvement Project (AgMIP): Protocols and pilot studies

  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 Elsevier ...

  Citation × Citation Citation Abstract Copy Title: The Agricultural Model Intercomparison and Improvement Project (AgMIP): Protocols and pilot studies Author: Porter, C., Antle, J. M., Asseng, S., Rosenzweig, C., Hatfield, J.L., Boote, K.J., Thorburn, P., Ewert, F., Basso, B., Wallach, D., Baigorria, G., Winter, J.M., Nelson, G.C., Jones, J.W., Janssen, S., Ruane, A.C. 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 Elsevier and can be found at: http://www.elsevier.com/. Title: The Agricultural Model Intercomparison and Improvement Project (AgMIP): Protocols and pilot studies Author: Porter, C., Antle, J. M., Asseng, S., Rosenzweig, C., Hatfield, J.L., Boote, K.J., Thorburn, P., Ewert, F., Basso, B., Wallach, D., Baigorria, G., Winter, J.M., Nelson, G.C., Jones, J.W., Janssen, S., Ruane, A.C. 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 Elsevier and can be found at: http://www.elsevier.com/. Close

• 40. [Article] Long-term fertilizer input influences total and bioavailable metal in agricultural soils and crops

  Protection of the quality and integrity of food supplies is of global concern. Crops can accumulate non-nutritive and sometimes toxic metals and metalloids. Accumulated metals/metalloids can come in part, ...

  Citation × Citation Citation Abstract Copy Title: Long-term fertilizer input influences total and bioavailable metal in agricultural soils and crops Author: Perez, Angela L. Protection of the quality and integrity of food supplies is of global concern. Crops can accumulate non-nutritive and sometimes toxic metals and metalloids. Accumulated metals/metalloids can come in part, from fertilizers, which may contain variable levels of non-nutritive metals or metalloids such as arsenic (As), cadmium (Cd), lead (Pb), nickel (Ni), and mercury (Hg). Metal bioavailability measurements can estimate crop metal accumulation and potential offsite movement. Diffusive Gradients in Thin Films (DGT) are used to measure labile, considered to be bioavailable, metal in soil solution. The DGT technique was applied in diverse agricultural soils receiving various applications of phosphate fertilizers. DGT was found to be marginally predictive of Cd accumulated in the edible portion of wheat (Triticum aestivum L.) and potato crops (Solanum tuberosum). A distinct approach was developed to estimate short and long-term changes to total and labile metal concentrations using a uniquely calculated distribution coefficient (Kd-BIO). Kd-BIO values for Cd and Ni did not decrease over the study period, indicating that soils may serve as a long-term contaminant sink. For As and Pb, there was a tendency for the Kd (As) and Kd-BIO (Pb) values to decrease with treatment and with yearly applications. If these tendencies were to continue, they may have long term implication for human health risk assessment. In general, total recoverable As, Pb, and Hg did not increase with fertilizer treatment level or over time in agricultural soils. Labile As and Pb dose response with fertilizer treatment was site specific. As and Pb were not detected in either crop throughout the study. Cd, Ni, and Hg were measured in wheat and potato. Kd-BIO was found to be a strong indicator of Ni and Cd accumulation in crops. Transfer coefficients (Tc) for Hg were calculated and determined to increase with time. Finally, the use of chemical profiling techniques to identify the geographic growing region of three fruits strawberry (Fragaria x ananassa), blueberry (Vaccinium caesariense/ corymbosum, and pear (Pyrus communis) was considered. The data were modeled with successful regional, sub-regional, and varietal classification ranging from 70 to 100% depending on commodity and model. Title: Long-term fertilizer input influences total and bioavailable metal in agricultural soils and crops Author: Perez, Angela L. Protection of the quality and integrity of food supplies is of global concern. Crops can accumulate non-nutritive and sometimes toxic metals and metalloids. Accumulated metals/metalloids can come in part, from fertilizers, which may contain variable levels of non-nutritive metals or metalloids such as arsenic (As), cadmium (Cd), lead (Pb), nickel (Ni), and mercury (Hg). Metal bioavailability measurements can estimate crop metal accumulation and potential offsite movement. Diffusive Gradients in Thin Films (DGT) are used to measure labile, considered to be bioavailable, metal in soil solution. The DGT technique was applied in diverse agricultural soils receiving various applications of phosphate fertilizers. DGT was found to be marginally predictive of Cd accumulated in the edible portion of wheat (Triticum aestivum L.) and potato crops (Solanum tuberosum). A distinct approach was developed to estimate short and long-term changes to total and labile metal concentrations using a uniquely calculated distribution coefficient (Kd-BIO). Kd-BIO values for Cd and Ni did not decrease over the study period, indicating that soils may serve as a long-term contaminant sink. For As and Pb, there was a tendency for the Kd (As) and Kd-BIO (Pb) values to decrease with treatment and with yearly applications. If these tendencies were to continue, they may have long term implication for human health risk assessment. In general, total recoverable As, Pb, and Hg did not increase with fertilizer treatment level or over time in agricultural soils. Labile As and Pb dose response with fertilizer treatment was site specific. As and Pb were not detected in either crop throughout the study. Cd, Ni, and Hg were measured in wheat and potato. Kd-BIO was found to be a strong indicator of Ni and Cd accumulation in crops. Transfer coefficients (Tc) for Hg were calculated and determined to increase with time. Finally, the use of chemical profiling techniques to identify the geographic growing region of three fruits strawberry (Fragaria x ananassa), blueberry (Vaccinium caesariense/ corymbosum, and pear (Pyrus communis) was considered. The data were modeled with successful regional, sub-regional, and varietal classification ranging from 70 to 100% depending on commodity and model. Close

• 41. [Article] Agricultural development and urban unemployment : a simulation analysis of the Nigerian economy

  The study critically analyzes the implication of various agricultural development policies on urban unemployment and income distribution. More specifically it focuses on the evaluation of agricultural policies ...

  Citation × Citation Citation Abstract Copy Title: Agricultural development and urban unemployment : a simulation analysis of the Nigerian economy Author: Byerlee, Derek Ronald The study critically analyzes the implication of various agricultural development policies on urban unemployment and income distribution. More specifically it focuses on the evaluation of agricultural policies at the macro-economic Level in the Nigerian economy. A system science and simulation approach is used to build and test a ten sector macro-economic model of the Nigerian economy to investigate the problem. The model simulates consumption, investment, employment and production endogenously. Validation of the model shows that it is capable of describing the major trends in the Nigerian economy for recent history. By interacting with a detailed agricultural sector model, the macro-model enables evaluation of agricultural policies in the context of the total economy after taking account of the important interactions between the agricultural and nonagricultural economies. In particular the model enables some measures of income distribution and employment to be included as targets of economic development planning together with the conventional target of growth. The model predicts that if current agricultural policies are continued, urban unemployment and income disparities will become increasingly more serious in Nigeria. Furthermore, the income differential between agriculture and nonagriculture is predicted to widen leading to a continuing increase in the rate of labor migration out of agriculture. The evaluation of two sets of agricultural policies, export crop modernization and food crop modernization, leads to a serious questioning of the present emphasis among development economists on agricultural development as a means of steadying the flow of rural-urban migration and reducing urban unemployment and rural-urban income inequities. Because of the considerable multiplier effects of increased agricultural incomes on nonagricultural incomes, both agricultural policies produced a wider differential between agricultural and nonagricultural incomes stimulating further labor migration out of agriculture. This effect was particularly acute in the case of the food modernization policy where the terms of trade turned against agriculture. Nevertheless both sets of policies and particularly the export modernization policy improved the disparity in self-employed earnings and wage earnings and produced a steady rise in nonagricultural self-employed earnings which, under current policies, were predicted to stagnate because of rising urban unemployment. Other policies to restrain wages and increase government employment demonstrated the considerable trade-off between various groups of the population arising out of the complexity of interactions between the agricultural and nonagricultural sectors. The macroeconomic simulation model is suggested as a useful approach to development planning where there is need to consider interactions between sectors and trade-offs between targets of development. Title: Agricultural development and urban unemployment : a simulation analysis of the Nigerian economy Author: Byerlee, Derek Ronald The study critically analyzes the implication of various agricultural development policies on urban unemployment and income distribution. More specifically it focuses on the evaluation of agricultural policies at the macro-economic Level in the Nigerian economy. A system science and simulation approach is used to build and test a ten sector macro-economic model of the Nigerian economy to investigate the problem. The model simulates consumption, investment, employment and production endogenously. Validation of the model shows that it is capable of describing the major trends in the Nigerian economy for recent history. By interacting with a detailed agricultural sector model, the macro-model enables evaluation of agricultural policies in the context of the total economy after taking account of the important interactions between the agricultural and nonagricultural economies. In particular the model enables some measures of income distribution and employment to be included as targets of economic development planning together with the conventional target of growth. The model predicts that if current agricultural policies are continued, urban unemployment and income disparities will become increasingly more serious in Nigeria. Furthermore, the income differential between agriculture and nonagriculture is predicted to widen leading to a continuing increase in the rate of labor migration out of agriculture. The evaluation of two sets of agricultural policies, export crop modernization and food crop modernization, leads to a serious questioning of the present emphasis among development economists on agricultural development as a means of steadying the flow of rural-urban migration and reducing urban unemployment and rural-urban income inequities. Because of the considerable multiplier effects of increased agricultural incomes on nonagricultural incomes, both agricultural policies produced a wider differential between agricultural and nonagricultural incomes stimulating further labor migration out of agriculture. This effect was particularly acute in the case of the food modernization policy where the terms of trade turned against agriculture. Nevertheless both sets of policies and particularly the export modernization policy improved the disparity in self-employed earnings and wage earnings and produced a steady rise in nonagricultural self-employed earnings which, under current policies, were predicted to stagnate because of rising urban unemployment. Other policies to restrain wages and increase government employment demonstrated the considerable trade-off between various groups of the population arising out of the complexity of interactions between the agricultural and nonagricultural sectors. The macroeconomic simulation model is suggested as a useful approach to development planning where there is need to consider interactions between sectors and trade-offs between targets of development. Close

• 42. [Article] Modeling surface water and groundwater interactions near Milton- Freewater, Oregon

  The gravel aquifer of the Oregon side of Walla Walla River Basin has a strong hydrologic connection to surface water through a series of springs, unlined irrigation canals, the Walla Walla River, numerous ...

  Citation × Citation Citation Abstract Copy Title: Modeling surface water and groundwater interactions near Milton- Freewater, Oregon Author: Petrides Jimenez, Aristides Crisostomos The gravel aquifer of the Oregon side of Walla Walla River Basin has a strong hydrologic connection to surface water through a series of springs, unlined irrigation canals, the Walla Walla River, numerous wells and, since 2004, artificial recharge to the shallow aquifer using infiltration basins. The finite element Integrated Water Flow Model (IWFM) developed by California Department of Water Resources was used to quantify all of the major hydrologic features of the basin. Using the information provided by the Walla Walla Basin Watershed Council, irrigation districts, and previous studies conducted at Oregon State University and by consultants, the model was setup and calibrated, and a water budget simulation was performed for the years of 2003 to 2006. It is shown that close to 96 percent of the land use water demand goes to agriculture growing 16 major crops. 60 percent of the water comes from surface water diversions flowing through unlined irrigation canals , which themselves lose 28 percent of their inflow to the unconfined gravel aquifer. The calibrated and validated model was used to simulate the flow of the Johnson Creek Springs, which were shown to have increased flow due to the artificial recharge project. Title: Modeling surface water and groundwater interactions near Milton- Freewater, Oregon Author: Petrides Jimenez, Aristides Crisostomos The gravel aquifer of the Oregon side of Walla Walla River Basin has a strong hydrologic connection to surface water through a series of springs, unlined irrigation canals, the Walla Walla River, numerous wells and, since 2004, artificial recharge to the shallow aquifer using infiltration basins. The finite element Integrated Water Flow Model (IWFM) developed by California Department of Water Resources was used to quantify all of the major hydrologic features of the basin. Using the information provided by the Walla Walla Basin Watershed Council, irrigation districts, and previous studies conducted at Oregon State University and by consultants, the model was setup and calibrated, and a water budget simulation was performed for the years of 2003 to 2006. It is shown that close to 96 percent of the land use water demand goes to agriculture growing 16 major crops. 60 percent of the water comes from surface water diversions flowing through unlined irrigation canals , which themselves lose 28 percent of their inflow to the unconfined gravel aquifer. The calibrated and validated model was used to simulate the flow of the Johnson Creek Springs, which were shown to have increased flow due to the artificial recharge project. Close

• 43. [Article] Soil quality assessment of Willamette Valley soils and root colonization potential by arbuscular mycorrhizal fungi

  Interest in measuring soil quality continues to increase worldwide in view of demands on land productivity and the necessity to preserve soil resources, yet identification of suitable indicators for soil ...

  Citation × Citation Citation Abstract Copy Title: Soil quality assessment of Willamette Valley soils and root colonization potential by arbuscular mycorrhizal fungi Author: Allen, Natalie M. Interest in measuring soil quality continues to increase worldwide in view of demands on land productivity and the necessity to preserve soil resources, yet identification of suitable indicators for soil quality assessment is still evolving. This study adapted 10 biological, physical, and chemical indicators of soil quality identified by the Cornell Soil Health Test and applied them to evaluate agricultural soils in the south Willamette Valley, Oregon, USA. Soil samples from 102 sites were tested for individual indicators of soil quality that were interpreted with scoring curves developed by the CSHT. Overall soil quality scores and individual soil quality indicators were analyzed in relation to agricultural practices including cropping cycle (perennial, annual, or fallow), soil disturbance (tilled, not tilled), or management type (organic, transitional, conventional). Data analysis by forward model selection using Bayesian Information Criteria indicated that certain management practices influence soil nitrate, surface and subsurface compaction, active carbon, potentially mineralizable nitrogen, and water stable aggregation. Several soil quality indicators under organic management were found to have more favorable values than under conventional management. Soil disturbance (tillage) resulted in decreased aggregate stability compared to undisturbed soils, but was associated with increased values for certain biological indicators such as organic matter decomposition and nutrient cycling. Root colonization potential by arbuscular mycorrhizal (AM) fungi was investigated as an additional indicator of biological soil quality, and to explore underlying relationships with soil quality measures and agricultural management practices. A subset of 33 soils was tested for root colonization potential in a greenhouse bioassay with sorghum as a trap plant. Cropping cycle had a large impact on AM root colonization potential; soil samples from fields planted to perennials resulted in greater root colonization than did soils from annual fields. No other management practice significantly affected AM root colonization potential. AM root colonization potential was not related to overall soil quality scores although a weak negative relationship was observed between AM root colonization potential and two individual indicators of soil quality: soil pH and subsurface compaction. Possible reasons for the apparent lack of sensitivity by AM fungal colonization to soil quality parameters are discussed. Title: Soil quality assessment of Willamette Valley soils and root colonization potential by arbuscular mycorrhizal fungi Author: Allen, Natalie M. Interest in measuring soil quality continues to increase worldwide in view of demands on land productivity and the necessity to preserve soil resources, yet identification of suitable indicators for soil quality assessment is still evolving. This study adapted 10 biological, physical, and chemical indicators of soil quality identified by the Cornell Soil Health Test and applied them to evaluate agricultural soils in the south Willamette Valley, Oregon, USA. Soil samples from 102 sites were tested for individual indicators of soil quality that were interpreted with scoring curves developed by the CSHT. Overall soil quality scores and individual soil quality indicators were analyzed in relation to agricultural practices including cropping cycle (perennial, annual, or fallow), soil disturbance (tilled, not tilled), or management type (organic, transitional, conventional). Data analysis by forward model selection using Bayesian Information Criteria indicated that certain management practices influence soil nitrate, surface and subsurface compaction, active carbon, potentially mineralizable nitrogen, and water stable aggregation. Several soil quality indicators under organic management were found to have more favorable values than under conventional management. Soil disturbance (tillage) resulted in decreased aggregate stability compared to undisturbed soils, but was associated with increased values for certain biological indicators such as organic matter decomposition and nutrient cycling. Root colonization potential by arbuscular mycorrhizal (AM) fungi was investigated as an additional indicator of biological soil quality, and to explore underlying relationships with soil quality measures and agricultural management practices. A subset of 33 soils was tested for root colonization potential in a greenhouse bioassay with sorghum as a trap plant. Cropping cycle had a large impact on AM root colonization potential; soil samples from fields planted to perennials resulted in greater root colonization than did soils from annual fields. No other management practice significantly affected AM root colonization potential. AM root colonization potential was not related to overall soil quality scores although a weak negative relationship was observed between AM root colonization potential and two individual indicators of soil quality: soil pH and subsurface compaction. Possible reasons for the apparent lack of sensitivity by AM fungal colonization to soil quality parameters are discussed. Close

• 44. [Article] Connections between science and business to increase environmentally-friendly food production

  This study represents an internship, as a requirement of the Professional Science Masters program at Oregon State University, performed with Western Ag Innovations Inc. The study consisted of two aspects ...

  Citation × Citation Citation Abstract Copy Title: Connections between science and business to increase environmentally-friendly food production Author: Rieder, Rebekka M. This study represents an internship, as a requirement of the Professional Science Masters program at Oregon State University, performed with Western Ag Innovations Inc. The study consisted of two aspects -- one business and one science oriented. The two objectives of this internship were to: 1) qualitatively evaluate how two agrarian groups, Pesticide-Free Production Farmer’s Cooperative and Shepherd’s Grain, benefit from environmentally-friendly production and certification; and 2) quantitatively determine the belowground soil nutrient supply dynamics of intercropping pea with wheat using PRSTM-probes in a dryland agricultural region of Northeastern Oregon. The agrarian group Shepherd’s Grain (SG) is located in the Pacific Northwest (PNW), USA, and the Pesticide-Free Production (PFP) Farmer’s co-op was centered in the Western Canadian prairies. These food producers were changing from production-oriented models to consumer-driven systems by acquiring eco-friendly production certification in order to access niche markets. SG was successful while the PFP Farmer’s co-op was unable to find value-added markets for their commodity products. A comparative case study was conducted to compare and contrast the two agrarian groups with regard to organizational structure and third party certification. This study identified several factors contributing to the success or the failure of the agrarian groups. The major factors for success were establishing contracts with consumers and preserving the identity of food products. Effective direct marketing to consumers -- with a clear message backed by eco-friendly certification, to initiate market demand for branded products -- was critical. By comparing SG and the PFP Farmer’s co-op, I found that market incentives can promote environmentally-friendly agricultural practices for sustainable crop production and increase farm profitability. This is consistent with present trends in agricultural production, which are driven by consumer demand for increased transparency and sustainable food production. Plant Root SimulatorTM (PRSTM)-probes sold commercially by Western Ag Innovations in Saskatoon, Canada, were used to quantitatively determine nutrient supply rates in a dryland intercropping wheat-pea system. Intercropping is an agriculture system that is not practiced in the PNW of the USA. However, intercropping has the potential to serve as a tool for increasing environmentally friendly agricultural practices. PRSTM-probes are not used extensively in PNW dryland cropping systems either. The purpose of this research was to determine the potential benefits of intercropping by using the PRSTM-probes as a diagnostic tool. PRSTM-probes were used to measure nutrient supply rates within established agronomic trials at Pendleton, OR. PRSTM-probes showed an increase in nitrogen (N) supply associated with the observed grain yield response to N fertilizer. Similarly, PRSTM-probes did not show a difference in nutrient supply for intercropping treatments when no grain yield response was observed. In general, intercropping did not benefit grain yield in this dryland agricultural system. PRSTMprobe measurements of nutrient supply were related to plant response to N fertilizer and intercropping treatments in a 1-year field experiment. Title: Connections between science and business to increase environmentally-friendly food production Author: Rieder, Rebekka M. This study represents an internship, as a requirement of the Professional Science Masters program at Oregon State University, performed with Western Ag Innovations Inc. The study consisted of two aspects -- one business and one science oriented. The two objectives of this internship were to: 1) qualitatively evaluate how two agrarian groups, Pesticide-Free Production Farmer’s Cooperative and Shepherd’s Grain, benefit from environmentally-friendly production and certification; and 2) quantitatively determine the belowground soil nutrient supply dynamics of intercropping pea with wheat using PRSTM-probes in a dryland agricultural region of Northeastern Oregon. The agrarian group Shepherd’s Grain (SG) is located in the Pacific Northwest (PNW), USA, and the Pesticide-Free Production (PFP) Farmer’s co-op was centered in the Western Canadian prairies. These food producers were changing from production-oriented models to consumer-driven systems by acquiring eco-friendly production certification in order to access niche markets. SG was successful while the PFP Farmer’s co-op was unable to find value-added markets for their commodity products. A comparative case study was conducted to compare and contrast the two agrarian groups with regard to organizational structure and third party certification. This study identified several factors contributing to the success or the failure of the agrarian groups. The major factors for success were establishing contracts with consumers and preserving the identity of food products. Effective direct marketing to consumers -- with a clear message backed by eco-friendly certification, to initiate market demand for branded products -- was critical. By comparing SG and the PFP Farmer’s co-op, I found that market incentives can promote environmentally-friendly agricultural practices for sustainable crop production and increase farm profitability. This is consistent with present trends in agricultural production, which are driven by consumer demand for increased transparency and sustainable food production. Plant Root SimulatorTM (PRSTM)-probes sold commercially by Western Ag Innovations in Saskatoon, Canada, were used to quantitatively determine nutrient supply rates in a dryland intercropping wheat-pea system. Intercropping is an agriculture system that is not practiced in the PNW of the USA. However, intercropping has the potential to serve as a tool for increasing environmentally friendly agricultural practices. PRSTM-probes are not used extensively in PNW dryland cropping systems either. The purpose of this research was to determine the potential benefits of intercropping by using the PRSTM-probes as a diagnostic tool. PRSTM-probes were used to measure nutrient supply rates within established agronomic trials at Pendleton, OR. PRSTM-probes showed an increase in nitrogen (N) supply associated with the observed grain yield response to N fertilizer. Similarly, PRSTM-probes did not show a difference in nutrient supply for intercropping treatments when no grain yield response was observed. In general, intercropping did not benefit grain yield in this dryland agricultural system. PRSTMprobe measurements of nutrient supply were related to plant response to N fertilizer and intercropping treatments in a 1-year field experiment. Close

• 45. [Article] Ammonia Volatilization from Nitrogen Fertilizers and Wastewater Reuse in the Columbia Basin

  Ammonia (NH₃) volatilization and loss from nitrogen (N) fertilizer in agriculture negatively impacts crops, farm profitability, human health and surrounding ecosystems where it is deposited. A significant ...

  Citation × Citation Citation Abstract Copy Title: Ammonia Volatilization from Nitrogen Fertilizers and Wastewater Reuse in the Columbia Basin Author: Del Moro, Sarah K. Ammonia (NH₃) volatilization and loss from nitrogen (N) fertilizer in agriculture negatively impacts crops, farm profitability, human health and surrounding ecosystems where it is deposited. A significant source of NH₃ volatilization occurs from surface application of urea on sandy soils with low pH buffering capacity such as those in the semi-arid Columbia Basin region of Oregon and Washington. Ammonia volatilization can be mitigated by using alternative N fertilizers to urea. Effluent from food processing and energy production industries is also used on cropland as an efficient method to conserve water and nutrients. However, NH₃ emissions from effluent application have not been quantified. The objectives of this study were to: (i) quantify NH₃-N loss from urea vs. alternative N fertilizer products in a micrometeorological field study and laboratory incubation experiment, and (ii) quantify NH₃ emissions from effluent applied to crops using an inverse-dispersion micrometeorological method. The fertilizers evaluated in field and laboratory trials included urea, polymer-coated urea, sulfur-coated urea, urea treated with urease inhibitor [N-(n-butyl) thiophosphoric triamide (NBPT)] and ammonium sulfate (AS). Mixed and fused N salts were also evaluated, including a blend of urea and AS and a blend of AS:ammonium nitrate (AN). A modified passive flux method was used to estimate NH₃-N loss from fertilizers in the field experiment for 33 d after application. In the lab incubation trial, NH₃ was collected in acid for 43 d after application. In the field trial, cumulative NH₃-N loss from urea was 47% of N applied. The alternative N fertilizers reduced NH₃-N loss in both the field and laboratory, with the exception of the fused urea:AS blend. The reduction of NH₃-N loss ranged from 19 to 68% vs. urea in the field, and 16 to 98% vs. urea in the laboratory. In the second study, a backward Lagrangian stochastic (bLS) model was used to calculate NH₃ emissions from alfalfa fields receiving effluent water (average 111 mg L⁻¹ total Kjeldahl N content) generated from a potato processor, a dehydrated onion processor, and a cogeneration plant. An ultraviolet-differential optical absorption spectrometer (UV-DOAS) and three-dimensional sonic anemometer were used to monitor NH₃ concentrations, wind speed, and temperature for 43 days downwind of the field. The average NH₃-N emission rate was 1.4 kg ha⁻¹ d⁻¹ when effluent was applied vs. 0.5 kg ha⁻¹ d⁻¹ during irrigation without effluent. The greatest average NH₃-N emission rate of 6.1 kg ha⁻¹ d⁻¹ resulted from alfalfa harvest. These studies provided insight of relative NH₃ loss among a variety of alternative N fertilizers to urea. Additional N mass balance research will be required to validate the accuracy of these NH₃ loss quantifications. Compared to urea, all of the alternative fertilizers significantly reduced NH₃-N loss, with greatest benefit resulting from NO₃⁻ and NH₄⁺ fertilizer forms (> 60% reduction vs. urea). The average NH₃-N emission rate of 1.4 kg ha⁻¹ d⁻¹ observed during effluent application was nearly three times the rate observed from irrigation without effluent. This study confirmed the potential of alternative N fertilizers to reduce NH₃ emission in agriculture in conditions favoring NH₃ volatilization. This study also confirmed the need to consider NH₃ loss when reusing effluent as a nutrient source for crops. Title: Ammonia Volatilization from Nitrogen Fertilizers and Wastewater Reuse in the Columbia Basin Author: Del Moro, Sarah K. Ammonia (NH₃) volatilization and loss from nitrogen (N) fertilizer in agriculture negatively impacts crops, farm profitability, human health and surrounding ecosystems where it is deposited. A significant source of NH₃ volatilization occurs from surface application of urea on sandy soils with low pH buffering capacity such as those in the semi-arid Columbia Basin region of Oregon and Washington. Ammonia volatilization can be mitigated by using alternative N fertilizers to urea. Effluent from food processing and energy production industries is also used on cropland as an efficient method to conserve water and nutrients. However, NH₃ emissions from effluent application have not been quantified. The objectives of this study were to: (i) quantify NH₃-N loss from urea vs. alternative N fertilizer products in a micrometeorological field study and laboratory incubation experiment, and (ii) quantify NH₃ emissions from effluent applied to crops using an inverse-dispersion micrometeorological method. The fertilizers evaluated in field and laboratory trials included urea, polymer-coated urea, sulfur-coated urea, urea treated with urease inhibitor [N-(n-butyl) thiophosphoric triamide (NBPT)] and ammonium sulfate (AS). Mixed and fused N salts were also evaluated, including a blend of urea and AS and a blend of AS:ammonium nitrate (AN). A modified passive flux method was used to estimate NH₃-N loss from fertilizers in the field experiment for 33 d after application. In the lab incubation trial, NH₃ was collected in acid for 43 d after application. In the field trial, cumulative NH₃-N loss from urea was 47% of N applied. The alternative N fertilizers reduced NH₃-N loss in both the field and laboratory, with the exception of the fused urea:AS blend. The reduction of NH₃-N loss ranged from 19 to 68% vs. urea in the field, and 16 to 98% vs. urea in the laboratory. In the second study, a backward Lagrangian stochastic (bLS) model was used to calculate NH₃ emissions from alfalfa fields receiving effluent water (average 111 mg L⁻¹ total Kjeldahl N content) generated from a potato processor, a dehydrated onion processor, and a cogeneration plant. An ultraviolet-differential optical absorption spectrometer (UV-DOAS) and three-dimensional sonic anemometer were used to monitor NH₃ concentrations, wind speed, and temperature for 43 days downwind of the field. The average NH₃-N emission rate was 1.4 kg ha⁻¹ d⁻¹ when effluent was applied vs. 0.5 kg ha⁻¹ d⁻¹ during irrigation without effluent. The greatest average NH₃-N emission rate of 6.1 kg ha⁻¹ d⁻¹ resulted from alfalfa harvest. These studies provided insight of relative NH₃ loss among a variety of alternative N fertilizers to urea. Additional N mass balance research will be required to validate the accuracy of these NH₃ loss quantifications. Compared to urea, all of the alternative fertilizers significantly reduced NH₃-N loss, with greatest benefit resulting from NO₃⁻ and NH₄⁺ fertilizer forms (> 60% reduction vs. urea). The average NH₃-N emission rate of 1.4 kg ha⁻¹ d⁻¹ observed during effluent application was nearly three times the rate observed from irrigation without effluent. This study confirmed the potential of alternative N fertilizers to reduce NH₃ emission in agriculture in conditions favoring NH₃ volatilization. This study also confirmed the need to consider NH₃ loss when reusing effluent as a nutrient source for crops. Close

• 46. [Article] Crop and tree response to planting patterns in alley cropping systems

  Growing trees as a green manure crop together with an annual food crop is a new technology for farmers in Oregon. To promote farmer participation and to acquire a broad knowledge of the processes involved ...

  Citation × Citation Citation Abstract Copy Title: Crop and tree response to planting patterns in alley cropping systems Author: Seiter, Stefan Growing trees as a green manure crop together with an annual food crop is a new technology for farmers in Oregon. To promote farmer participation and to acquire a broad knowledge of the processes involved in species interactions, three feasible alley cropping and two sweet corn monocrop planting patterns were studied in a replicated factorial experiment. Each alley cropping pattern was planted twice, with either red alder (Alnus rubra Bong) or black locust (Robinia pseudoacacia L.). The annual crop component used was sweet corn (Zea mays L.). Sweet com population was the same in all plant arrangements, except one alley cropping pattern. The monocrop control, planted at 63.5 cm row spacing, yielded highest while the lowest com yield was produced in the alley cropping system that involved alternate com and black locust rows. The highest com yield produced among alley cropping patterns surpassed the control planted at 89 cm row spacing. Com yield in planting patterns was dependent on the relative space occupied by each species. A high ratio of tree occupation was negatively correlated with com yield. Greatest pruning biomass was produced in alley cropping systems with highest tree population and greatest percentage of tree space occupation. Compared to black locust, biomass produced by red alder trees was minimal. Within alley cropping patterns of the same tree species, lower crop yield coincided with highest pruning biomass implicating trade-offs between potential soil improving effects and crop yield. Tree biomass was more strongly affected by changes in relative space occupation than com yield. Yield of individual com rows within treatments varied considerably. In alley cropping systems where several com rows were separated by double rows of trees, com rows adjacent to trees yielded significantly more than those neighboring com rows on either side. Com row position had no significant effect in monocrop or patterns where tree and com alternated. Mean yield of individual com plants decreased when both neighboring com rows and neighboring tree row were in close proximity. The approach of using a few planting patterns as experimental treatments did not permit to precisely model the relationships between single proximity factors and yield components. However, the approach permitted identification of factors contributing the most to changes in tree and crop yield and demonstrated basic trends. Title: Crop and tree response to planting patterns in alley cropping systems Author: Seiter, Stefan Growing trees as a green manure crop together with an annual food crop is a new technology for farmers in Oregon. To promote farmer participation and to acquire a broad knowledge of the processes involved in species interactions, three feasible alley cropping and two sweet corn monocrop planting patterns were studied in a replicated factorial experiment. Each alley cropping pattern was planted twice, with either red alder (Alnus rubra Bong) or black locust (Robinia pseudoacacia L.). The annual crop component used was sweet corn (Zea mays L.). Sweet com population was the same in all plant arrangements, except one alley cropping pattern. The monocrop control, planted at 63.5 cm row spacing, yielded highest while the lowest com yield was produced in the alley cropping system that involved alternate com and black locust rows. The highest com yield produced among alley cropping patterns surpassed the control planted at 89 cm row spacing. Com yield in planting patterns was dependent on the relative space occupied by each species. A high ratio of tree occupation was negatively correlated with com yield. Greatest pruning biomass was produced in alley cropping systems with highest tree population and greatest percentage of tree space occupation. Compared to black locust, biomass produced by red alder trees was minimal. Within alley cropping patterns of the same tree species, lower crop yield coincided with highest pruning biomass implicating trade-offs between potential soil improving effects and crop yield. Tree biomass was more strongly affected by changes in relative space occupation than com yield. Yield of individual com rows within treatments varied considerably. In alley cropping systems where several com rows were separated by double rows of trees, com rows adjacent to trees yielded significantly more than those neighboring com rows on either side. Com row position had no significant effect in monocrop or patterns where tree and com alternated. Mean yield of individual com plants decreased when both neighboring com rows and neighboring tree row were in close proximity. The approach of using a few planting patterns as experimental treatments did not permit to precisely model the relationships between single proximity factors and yield components. However, the approach permitted identification of factors contributing the most to changes in tree and crop yield and demonstrated basic trends. Close

• 47. [Article] Strategic investments in agricultural industries and Oregon's economic development

  This research is concerned with the current debate among Oregonians on how to improve the standard of living and accelerate economic development in Oregon. The main question is what economic activities ...

  Citation × Citation Citation Abstract Copy Title: Strategic investments in agricultural industries and Oregon's economic development Author: Koong, Dennis T This research is concerned with the current debate among Oregonians on how to improve the standard of living and accelerate economic development in Oregon. The main question is what economic activities make Oregon, and regions within Oregon grow? To find out where Oregon's economic strength and weaknesses lie, first we have to understand the income and employment contributions of different industries in Oregon. Second, decisions for improving Oregon's economic growth may be guided by investment in the production of goods for which Oregon is competitive relative to other goods in domestic and international regions. Third, we can investigate and hypothesize about reasons for strengths and weaknesses of Oregon's industries relative to other industries locally, nationally, and internationally. To provide a guideline for Oregon economic development, this study first classifies Oregon's economic activities into eight major economic sectors: agriculture, lumber and wood, high-tech, other manufacturing, non-financial private services, financial services, other private services, and government services. In 1995, it is estimated that these sectors generated about $72 billion in gross state product (GSP) for Oregon's economy, employed over 1.4 million people and provided total payroll of about $36.5 billion. Oregon's aggregate service sector, which includes both nongovernment private services and government services, generated about 76% of Oregon's gross state product (64% and 12% respectively), received about 76% of Oregon's payroll (58% and 18% respectively), and employed about 80% of Oregon's total employment (64% and 16% respectively). The wood sector contributed about 7% to Oregon's GSP, received 6% of Oregon's payroll, and employed about 5% of Oregon's employment. The agriculture sector generated about 7% of Oregon's GSP, received about 4% of Oregon's payroll, and accounted for about 5% of Oregon's employment. The high-tech industries contributed about 5% of Oregon's GSP, received 7% of Oregon's payroll, and employed about 4% of employment. Oregon exported about $ 9.43 billion in 1995. High-tech equipment exports were about 46% of Oregon's total exports. The agriculture sector accounted for 26%, of exports, the wood sector exported 15%, and other manufacturing products 13%. While Oregon's recent growth has accured mostly through aggregate service activities, the trade oriented sectors including agriculture, wood, and high-tech injected nearly nine and half billion dollars of foreign revenue into the state's economy in 1995. Second, this research utilizes state-level statistics along with "revealed comparative advantage" methodology and computes competitiveness indexes. These are calculated for individual industries in Oregon relative to the Pacific Northwest and the United States economies to illustrate the strengths and weaknesses of the Oregon economy. The comparison of Oregon's efficiency in the agricultural sector relative to the PNW and U.S. indicates that, in the last seven years, Oregon's comparative advantage in agricultural farm production (crops) has increased but its comparative advantage in food processing has been declining since 1992. In fact, in 1994 and 1995 Oregon exhibited a comparative disadvantage in food products relative to both the PNW and the United States economies. One hypothesis advanced in this study is that such decline may be due to the Oregon's higher labor costs relative to other states in the PNW and U.S. The possibility that Oregon pays higher wages to workers in food production relative to the PNW and U.S., combined with the notion that food production in Oregon is more labor-intensive relative to the PNW and U.S. may account for the fact that Oregon's comparative advantage in food processing has declined in recent years. With regard to the wood sector, Oregon has a comparative advantage in lumber and wood products relative to both the PNW and U.S. economies In the furniture and fixtures category Oregon holds a clear comparative advantage against the PNW region, however it has a distinct disadvantage compared to the United States economy. In the paper products, Oregon holds a comparative advantage relative to the U.S., however, Oregon is at a comparative disadvantage relative to the PNW (except for 1991 and 1992 when Oregon had a slight comparative advantage). During the 1989-1995 time period, Oregon has been more competitive relative to the PNW region in industrial machinery and computer equipment. However, the degree of advantage has declined from 157% in 1989, to 105% in 1995. Relative to U.S., Oregon improved its comparative advantage in the production of same goods from -16% comparative disadvantage in 1989, to being +25% more efficient in 1995. Similarly, Oregon held its comparative advantage in the production of electric equipment and measuring instruments relative to PNW during 1989-1995 time period. Relative to U.S., Oregon improved its efficiency in the production of electric equipment from -37% inefficiency in 1989, to +5% of comparative advantage in 1995. Oregon's comparative advantage in measuring instrument varied between 11% and 26% over 1989-1995 time period. With regard to recent arguments advanced against high-tech industries, the results of this study indicate that Oregon is becoming more efficient (regionally as well as nationally) in manufacture of high-tech products, this may be partially be due to economies of scale associated with this sector. With regards to food processing industries, it may be that costs associated with labor, materials, capital investment, and other inputs are high relative to other regions. Hence, we cannot be competitive in those industries. Alternatively, one may argue that labor productivity in Oregon's food industry is lower than other regions. If this is the case, increasing training and education programs to increase labor productivity, in addition to changing infrastructure, could improve efficiency in food industries and thereby improve Oregon's economic development. Title: Strategic investments in agricultural industries and Oregon's economic development Author: Koong, Dennis T This research is concerned with the current debate among Oregonians on how to improve the standard of living and accelerate economic development in Oregon. The main question is what economic activities make Oregon, and regions within Oregon grow? To find out where Oregon's economic strength and weaknesses lie, first we have to understand the income and employment contributions of different industries in Oregon. Second, decisions for improving Oregon's economic growth may be guided by investment in the production of goods for which Oregon is competitive relative to other goods in domestic and international regions. Third, we can investigate and hypothesize about reasons for strengths and weaknesses of Oregon's industries relative to other industries locally, nationally, and internationally. To provide a guideline for Oregon economic development, this study first classifies Oregon's economic activities into eight major economic sectors: agriculture, lumber and wood, high-tech, other manufacturing, non-financial private services, financial services, other private services, and government services. In 1995, it is estimated that these sectors generated about $72 billion in gross state product (GSP) for Oregon's economy, employed over 1.4 million people and provided total payroll of about $36.5 billion. Oregon's aggregate service sector, which includes both nongovernment private services and government services, generated about 76% of Oregon's gross state product (64% and 12% respectively), received about 76% of Oregon's payroll (58% and 18% respectively), and employed about 80% of Oregon's total employment (64% and 16% respectively). The wood sector contributed about 7% to Oregon's GSP, received 6% of Oregon's payroll, and employed about 5% of Oregon's employment. The agriculture sector generated about 7% of Oregon's GSP, received about 4% of Oregon's payroll, and accounted for about 5% of Oregon's employment. The high-tech industries contributed about 5% of Oregon's GSP, received 7% of Oregon's payroll, and employed about 4% of employment. Oregon exported about $ 9.43 billion in 1995. High-tech equipment exports were about 46% of Oregon's total exports. The agriculture sector accounted for 26%, of exports, the wood sector exported 15%, and other manufacturing products 13%. While Oregon's recent growth has accured mostly through aggregate service activities, the trade oriented sectors including agriculture, wood, and high-tech injected nearly nine and half billion dollars of foreign revenue into the state's economy in 1995. Second, this research utilizes state-level statistics along with "revealed comparative advantage" methodology and computes competitiveness indexes. These are calculated for individual industries in Oregon relative to the Pacific Northwest and the United States economies to illustrate the strengths and weaknesses of the Oregon economy. The comparison of Oregon's efficiency in the agricultural sector relative to the PNW and U.S. indicates that, in the last seven years, Oregon's comparative advantage in agricultural farm production (crops) has increased but its comparative advantage in food processing has been declining since 1992. In fact, in 1994 and 1995 Oregon exhibited a comparative disadvantage in food products relative to both the PNW and the United States economies. One hypothesis advanced in this study is that such decline may be due to the Oregon's higher labor costs relative to other states in the PNW and U.S. The possibility that Oregon pays higher wages to workers in food production relative to the PNW and U.S., combined with the notion that food production in Oregon is more labor-intensive relative to the PNW and U.S. may account for the fact that Oregon's comparative advantage in food processing has declined in recent years. With regard to the wood sector, Oregon has a comparative advantage in lumber and wood products relative to both the PNW and U.S. economies In the furniture and fixtures category Oregon holds a clear comparative advantage against the PNW region, however it has a distinct disadvantage compared to the United States economy. In the paper products, Oregon holds a comparative advantage relative to the U.S., however, Oregon is at a comparative disadvantage relative to the PNW (except for 1991 and 1992 when Oregon had a slight comparative advantage). During the 1989-1995 time period, Oregon has been more competitive relative to the PNW region in industrial machinery and computer equipment. However, the degree of advantage has declined from 157% in 1989, to 105% in 1995. Relative to U.S., Oregon improved its comparative advantage in the production of same goods from -16% comparative disadvantage in 1989, to being +25% more efficient in 1995. Similarly, Oregon held its comparative advantage in the production of electric equipment and measuring instruments relative to PNW during 1989-1995 time period. Relative to U.S., Oregon improved its efficiency in the production of electric equipment from -37% inefficiency in 1989, to +5% of comparative advantage in 1995. Oregon's comparative advantage in measuring instrument varied between 11% and 26% over 1989-1995 time period. With regard to recent arguments advanced against high-tech industries, the results of this study indicate that Oregon is becoming more efficient (regionally as well as nationally) in manufacture of high-tech products, this may be partially be due to economies of scale associated with this sector. With regards to food processing industries, it may be that costs associated with labor, materials, capital investment, and other inputs are high relative to other regions. Hence, we cannot be competitive in those industries. Alternatively, one may argue that labor productivity in Oregon's food industry is lower than other regions. If this is the case, increasing training and education programs to increase labor productivity, in addition to changing infrastructure, could improve efficiency in food industries and thereby improve Oregon's economic development. Close

• 48. [Article] Cover crop nitrogen for summer vegetable crops

  Declared out of print August 2012. Published December 2003. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: h...

  Citation × Citation Citation Abstract Copy Title: Cover crop nitrogen for summer vegetable crops Author: Sandeno, J., Hemphill, D., Burket, John Zimmerman, 1953-, Oregon State University. Extension Service, Dick, R. Declared out of print August 2012. Published December 2003. 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: Cover crop nitrogen for summer vegetable crops Author: Sandeno, J., Hemphill, D., Burket, John Zimmerman, 1953-, Oregon State University. Extension Service, Dick, R. Declared out of print August 2012. Published December 2003. 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

• 49. [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

• 50. [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