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Registros recuperados: 79
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EVALUATING THE RETURNS TO VARIABLE RATE NITROGEN APPLICATION AgEcon
Roberts, Roland K.; English, Burton C.; Mahajanashetti, S.B..
Potential benefits of variable rate nitrogen application are illustrated and information needs identified. Lower costs of precision farming services, higher crop prices, and greater divergence in yield response potentials across management zones reduce the spatial variability required for profitable variable rate application. Information needs include identification and measurement of management zones within a field and estimation of management zone yield response functions, crop and input prices, and the cost of precision farming services.
Tipo: Journal Article Palavras-chave: Production economics; Management zones; Nitrogen; Precision farming; Spatial break-even variability proportions; Variable rate applications; Yield response variability; Crop Production/Industries.
Ano: 2000 URL: http://purl.umn.edu/15393
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Will Variable Rate Application Technology Pay in Tennessee? AgEcon
Cochran, Rebecca L.; Larson, James A.; Roberts, Roland K.; English, Burton C..
Costs differ among variable rate application systems. Most feasible in Tennessee are the 1-bin and 2-bin spreader beds mounted to existing chassis with an owner-added variable rate controller and global positioning system. Truck spreader systems required more acreage or larger custom charges making it difficult to breakeven and earn a profit.
Tipo: Conference Paper or Presentation Palavras-chave: Cotton; Grid soil sampling; Precision farming; Site-specific information; Variable rate application; Research and Development/Tech Change/Emerging Technologies.
Ano: 2004 URL: http://purl.umn.edu/34678
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Optimal Nitrogen Fertilization Rates in Winter Wheat Production as Affected by Risk, Disease, and Nitrogen Source AgEcon
Roberts, Roland K.; Walters, Jeremy T.; Larson, James A.; English, Burton C.; Howard, Donald D..
Interactions among the nitrogen (N) fertilization rate, N source, and disease severity can affect mean yield and yield in conservation tillage wheat production. A Just-Pope model was used to evaluate the effects of N rate, N source, and disease on the spring N fertilization decision. Ammonium nitrate (AN) was the utility-maximizing N source, regardless of risk preferences. The net-return-maximizing AN rate was 92 lb N/acre, providing $0.52/acre higher net returns than the best alternative N source (urea). If a farmer could anticipate a higher-than-average Take-All Root Rot infection, the difference in optimal net returns between AN and urea would increase to $35.11/acre.
Tipo: Journal Article Palavras-chave: Certainty equivalent; Blume-Blotch; Nitrogen fertilizer; Nitrogen source; Risk; Take-All; Winter wheat; D21; D81; Q12.
Ano: 2004 URL: http://purl.umn.edu/43444
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Impacts of the Boom-Bust Cycle on the Effectiveness of Policies for Moderating the Consequences of Sprawl on Residential Development AgEcon
Kim, Seung Gyu; Cho, Seong-Hoon; Lambert, Dayton M.; Roberts, Roland K..
Tipo: Conference Paper or Presentation Palavras-chave: Urban sprawl; Spatial discrete-choice model; Land Economics/Use.
Ano: 2011 URL: http://purl.umn.edu/103750
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Factors Affecting Perceived Improvements in Environmental Quality from Precision Farming AgEcon
Larkin, Sherry L.; Perruso, Larry; Marra, Michele C.; Roberts, Roland K.; English, Burton C.; Larson, James A.; Cochran, Rebecca L.; Martin, Steven W..
This study identified the factors that influenced whether farmers in the Southeastern United States perceived an improvement in environmental quality from adopting precision farming technologies (PFTs). Farmers with larger farms or higher yields were more likely to believe that they observed positive externalities associated with PFTs. Farmers who found PFTs profitable or who believed input reduction was important had higher probabilities whereas those with higher incomes or who were more dependent on farm income were less likely to perceive such benefits. Interestingly, the importance of environmental quality and length of time using PFTs were not found to affect the probability of perceiving an improvement in environmental quality.
Tipo: Journal Article Palavras-chave: Precision agriculture; Site-specific farming; Variable rate application; C25; Q12; Q24.
Ano: 2005 URL: http://purl.umn.edu/42787
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Adoption of Conservation-Tillage Practices in Cotton Production AgEcon
Banerjee, Swagata (Ban); Martin, Steven W.; Roberts, Roland K.; Larson, James A.; Hogan, Robert J., Jr.; Johnson, Jason L.; Paxton, Kenneth W.; Reeves, Jeanne M..
Replaced with revised version of paper 10/23/07.
Tipo: Conference Paper or Presentation Palavras-chave: Conservation tillage; Cotton; Genetically modified seed; Herbicide-resistant cotton; Stacked-gene cotton; Simultaneous logit model; Single-equation logit model; Technology adoption; Crop Production/Industries.
Ano: 2007 URL: http://purl.umn.edu/34842
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Factors Affecting Hay Supply and Demand in Tennessee AgEcon
Bazen, Ernest F.; Roberts, Roland K.; Travis, John; Larson, James A..
Understanding the interactions between supply and demand for hay is important because of hay’s significance to the agricultural sector and economy, and because hay is an important crop on highly erodible soils. As an example, Tennessee has the most erodible cultivated cropland in the United States (Denton, 2000), nearly half of the state’s current CRP acreage contracts are set to expire in 2007 (U.S. Department of Agriculture, 2006), and hay is one of the most economically important crops produced in the state (U.S. Department of Agriculture, 2004). Cross (1999) attributed the upward trend in Tennessee hay acreage since 1980 to an increasing number of farmers who were searching for alternative production activities, such as hay, pasture and livestock, to...
Tipo: Conference Paper or Presentation Palavras-chave: Acreage response; Derived demand; Elasticities; Hay; Inverse demand function; Price flexibilities; Yield response; Crop Production/Industries; Demand and Price Analysis; D.
Ano: 2008 URL: http://purl.umn.edu/6889
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AJAE Appendix: Challenges to the Development of a Dedicated Energy Crop AgEcon
Epplin, Francis M.; Clark, Christopher D.; Roberts, Roland K.; Hwang, Seonghuyk.
The material contained herein is supplementary to the article named in the title and published in the American Journal of Agricultural Economics, Volume 89, Number 5, December 2007.
Tipo: Journal Article Palavras-chave: Crop Production/Industries; Research and Development/Tech Change/Emerging Technologies.
Ano: 2007 URL: http://purl.umn.edu/7072
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FERTILIZER DEMAND FUNCTIONS FOR FIVE CROPS IN THE UNITED STATES AgEcon
Gunjal, Kisan R.; Roberts, Roland K.; Heady, Earl O..
Tipo: Journal Article Palavras-chave: Crop Production/Industries.
Ano: 1980 URL: http://purl.umn.edu/29473
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EFFECTS OF RISK, DISEASE, AND NITROGEN SOURCE ON OPTIMAL NITROGEN FERTILIZATION RATES IN WINTER WHEAT PRODUCTION AgEcon
Howard, Donald D.; English, Burton C.; Larson, James A.; Roberts, Roland K.; Walters, Jeremy T..
Interactions among nitrogen (N) fertilization rate, N source, and disease severity can affect mean yield and yield variance in conservation tillage wheat production. A Just-Pope model was used to evaluate the effects of N rate, N source, and disease on the spring N-fertilization decision. Ammonium nitrate (AN) was the utility-maximizing N source regardless of risk preferences. The net-return-maximizing AN rate was 92 lb N/acre, providing $0.52/acre higher net returns than the best alternative N source (urea). If a farmer could anticipate a higher than average Take-All infection, the difference in optimal net-returns between AN and urea would increase to $35.11/acre.
Tipo: Conference Paper or Presentation Palavras-chave: Crop Production/Industries.
Ano: 2004 URL: http://purl.umn.edu/34688
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AN ANALYSIS OF FACTORS ASSOCIATED WITH COMPOSTING BEHAVIOR AT THE HOUSEHOLD LEVEL AgEcon
Park, William M.; Lamons, Kevin S.; Roberts, Roland K..
Drawing upon telephone survey data, a logit probability analysis was conducted to identify household characteristics as well as social and institutional factors associated with backyard composting of yard and food wastes. Highly significant predictors included household gardening, perception of effort required, peer influence, and a compost bin sale program.
Tipo: Conference Paper or Presentation Palavras-chave: Consumer/Household Economics; Institutional and Behavioral Economics.
Ano: 1998 URL: http://purl.umn.edu/20836
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OPTIMAL PLANT POPULATION FOR ULTRA-NARROW-ROW COTTON PRODUCTION AS INFLUENCED BY LINT AND TRANSGENIC SEED PRICES AgEcon
Larson, James A.; Gwathmey, C. Owen; Roberts, Roland K..
Farmers are concerned about the high costs of transgenic seed and technology fees associated with the large plant population densities recommended for ultra-narrow row cotton. This study evaluated the effects of alternative plant population density decision criteria on net revenues under different lint price and transgenic seed cost scenarios. Results indicate that farmers may be able to maximize profits by seeding for a target plant population density of approximately 15.5 plants m-2.
Tipo: Conference Paper or Presentation Palavras-chave: Crop Production/Industries.
Ano: 2003 URL: http://purl.umn.edu/36004
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STATE-LEVEL ANALYSIS OF NATIONAL BEEF POLICY: THE USE OF STATE ECONOMETRIC MODELS AgEcon
Roberts, Roland K.; Martin, William J..
Interest has grown in analyzing the impact of national imports of foreign beef on state agricultural sectors. In this study, an interfaced Hawaiian-national model is simulated for a change in national beef imports. Hawaiian and national impacts demonstrate wide variation in both sign and magnitude. Usefulness of state models is emphasized for situations where state impacts of national policies are of interest.
Tipo: Journal Article Palavras-chave: Agricultural and Food Policy.
Ano: 1984 URL: http://purl.umn.edu/29735
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TRANSPORTATION COSTS IN ECONOMETRIC MODELS OF STATE AGRICULTURAL SECTORS: THE CASE OF BEEF IN HAWAII AgEcon
Roberts, Roland K..
Econometric models designed to show how national policies affect state agricultural sectors often use national prices as proxies for state prices. Consequently, they ignore the influence of freight rates on state production. An application to the Hawaii beef industry demonstrates that both freight rates and national beef prices have important impacts on Hawaii beef prices and production. By using state prices rather than national prices, error from changes in freight rates might be reduced, and the model's capacity for policy analysis might be broadened.
Tipo: Journal Article Palavras-chave: Livestock Production/Industries.
Ano: 1985 URL: http://purl.umn.edu/32522
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The Variable-Rate Decision for Multiple Inputs with Multiple Management Zones AgEcon
Larson, James A.; English, Burton C.; Roberts, Roland K..
Research has evaluated the relative profitability of variable-rate versus uniform-rate application of a single input in fields with multiple management zones. This paper addresses the variable-rate decision for multiple inputs. The decision-making framework is evaluated for nitrogen and water applied to irrigated cotton in fields with three management zones.
Tipo: Conference Paper or Presentation Palavras-chave: Crop Production/Industries.
Ano: 2005 URL: http://purl.umn.edu/35573
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Economic Feasibility of Kenaf Production in Three Tennessee Counties AgEcon
Bazen, Ernest F.; Roberts, Roland K.; English, Burton C..
Since the 1940s, kenaf has been viewed as a potential source of fiber, mainly for newsprint and high quality paper. Kenaf research has once again risen to the forefront due to the recent USDA tobacco buyout. Many states and farmers dependent upon tobacco revenues have been seeking alternative crops for a number of years. This study seeks to expand the current literature by examining the economic feasibility of growing kenaf within three counties in Tennessee. Nitrogen meta-yield response functions for kenaf and four traditional crops were developed for 30 soils through crop growth simulation modeling and used to compare optimal crop budgets for each soil. Results reveal that kenaf would not compete favorably with traditional crops on any soil at prices...
Tipo: Journal Article Palavras-chave: Alternative crop; Economic feasibility; Enterprise budgeting; Kenaf; Plant growth modeling; Yield response functions; Agribusiness; Crop Production/Industries.
Ano: 2006 URL: http://purl.umn.edu/62274
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Effects of Alternative Lime Application Rates on Cotton Profitability with Varying Cover Crops, Nitrogen, and Tillage Methods. AgEcon
Cochran, Rebecca L.; Larson, James A.; Roberts, Roland K.; Tyler, Donald D..
Soil acidity and cotton yields are influenced by cover crop, nitrogen, and tillage method. Applying half the recommended lime rate may be possible without reducing cotton yields. Using a nitrogen intensive cover crop and applying less nitrogen should mitigate the effects on soil acidity and yields.
Tipo: Conference Paper or Presentation Palavras-chave: Cover crops; Cotton; Lime; Nitrogen; Profitability; Soil acidity; Tillage; Crop Production/Industries.
Ano: 2005 URL: http://purl.umn.edu/35569
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FARMERS' PERCEPTIONS OF SPATIAL YIELD VARIABILITY AS INFLUENCED BY PRECISION FARMING INFORMATION GATHERING TECHNOLOGIES AgEcon
Roberts, Roland K.; Larson, James A..
This study evaluated how farmers' perceptions of spatial yield variability are influenced by precision technologies. Farmer estimates from a mail survey were regressed on use of alternative information technologies and personal characteristics. Results indicate that farmers who adopted yield monitors with GPS for cotton perceived significantly higher spatial yield variability.
Tipo: Conference Paper or Presentation Palavras-chave: Research and Development/Tech Change/Emerging Technologies.
Ano: 2004 URL: http://purl.umn.edu/34600
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ADOPTION OF SPATIAL INFORMATION GATHERING TECHNOLOGIES AND VARIABLE RATE INPUT APPLICATION TECHNOLOGIES BY COTTON FARMERS IN THE SOUTHEAST AgEcon
Martin, Steven W.; Roberts, Roland K.; English, Burton C.; Larson, James A.; Cochran, Rebecca L.; Goodman, W. Robert; Larkin, Sherry L.; Marra, Michele C.; Shurley, W. Donald; Reeves, Jeanne M..
Probit analysis identified factors influencing adoption of precision farming technologies by Southeastern cotton farmers. Younger, more educated farmers who operated larger farms and were optimistic about the future of precision farming were most likely to adopt site-specific information technology. The probability of adopting variable rate input application technology was higher for younger farmers who operated larger farms, owned more of the land they farmed, were more informed about the costs and benefits of precision farming, and were optimistic about the future of precision farming. Computer use was not important possibly because custom hiring shifts the burden of computer use to agribusiness firms.
Tipo: Conference Paper or Presentation Palavras-chave: Research and Development/Tech Change/Emerging Technologies.
Ano: 2004 URL: http://purl.umn.edu/34768
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Economic Analysis of the Effects of Winter Cover Crops on No-Tillage Corn Yield Response to Fertilizer Nitrogen AgEcon
Roberts, Roland K.; Larson, James A.; Tyler, Donald D.; Duck, Bob N.; Dillivan, Kim D..
Tipo: Conference Paper or Presentation Palavras-chave: Crop Production/Industries.
Ano: 1997 URL: http://purl.umn.edu/35851
Registros recuperados: 79
Primeira ... 1234 ... Última
 

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