Search

Search Results

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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