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Articles 121 - 131 of 131
Full-Text Articles in Agronomy and Crop Sciences
45th Annual North Central Extension-Industry Soil Fertility Conference, John E. Sawyer
45th Annual North Central Extension-Industry Soil Fertility Conference, John E. Sawyer
John E. Sawyer
If you would like to learn more about current soil fertility issues and research being conducted at universities across the North Central region, then consider attending the 45th Annual North Central Extension-Industry Soil Fertility Conference on November 4-5, 2015, from 1 p.m. to noon, at the Holiday Inn Airport in Des Moines, Iowa. The conference will include invited presentations from university and industry leaders, research reports from university soil fertility researchers, and posters outlining research by graduate students at universities across the North Central region (Illinois, Indiana, Iowa, Kansas, Kentucky, Michigan, Minnesota, Nebraska, North Dakota, Ohio, Ontario, Pennsylvania, South Dakota, …
Application Checkpoints For Fall Ammonia, H. Mark Hanna, John E. Sawyer
Application Checkpoints For Fall Ammonia, H. Mark Hanna, John E. Sawyer
John E. Sawyer
Depending on postharvest field conditions, some producers will soon be considering anhydrous ammonia application. Using fall labor to apply fertilizer can be attractive but needs to be balanced with the potential for nutrient loss. To avoid conversion of anhydrous ammonia from ammonium to more leachable forms of nitrogen, application should be delayed until average soil temperature is below 50°F and trending lower. Measure the 4-inch soil temperature at near 10 a.m. or 7 p.m. or check Iowa State University's county soil temperatures and forecast.
Apply Nitrogen Or Plant Corn?, John E. Sawyer
Apply Nitrogen Or Plant Corn?, John E. Sawyer
John E. Sawyer
The end of the optimal time for corn planting is quickly approaching. Getting corn planted should be a priority over making nitrogen (N) fertilizer applications. However, along with that decision there should be a plan to get N applications completed after planting and crop emergence. Switching products and application from preplant to sidedress requires availability of needed fertilizers and equipment. So have a plan in place.
Impact Of Swine Manure Applications On Nitrate And Phosphorus In Subsurface Drainage Water, Rameshwar S. Kanwar, James L. Baker, Carl H. Pederson, Antonio P. Mallarino, John E. Sawyer, Kenneth T. Pecinovsky
Impact Of Swine Manure Applications On Nitrate And Phosphorus In Subsurface Drainage Water, Rameshwar S. Kanwar, James L. Baker, Carl H. Pederson, Antonio P. Mallarino, John E. Sawyer, Kenneth T. Pecinovsky
John E. Sawyer
Nonpoint source nutrient pollution related to land application of manures is recognized as an important environmental and social issue for several reasons. First, manure from swine production facilities can have serious impacts on the quality of ground water resources. Second, several states are in the process of creating laws and/or regulations to reduce nitrogen (N) and phosphorus (P) loadings from manure to soil and water resources. Third, pollution of water resources from nutrients supplied by manure to croplands will help set parameters for developing public policies on the management of manure.
Impact Of Swine Manure Application On Water Quality, Rameshwar S. Kanwar, Carl H. Pederson, Matthew J. Helmers, John E. Sawyer, Antonio P. Mallarino
Impact Of Swine Manure Application On Water Quality, Rameshwar S. Kanwar, Carl H. Pederson, Matthew J. Helmers, John E. Sawyer, Antonio P. Mallarino
John E. Sawyer
Nonpoint source nutrient pollution related to land application of manures is recognized as an important environmental and social issue for several reasons. First,swine manure application to land can impact water quality. Second, several states are in the process of creating laws and/or regulations to reduce nitrogen and phosphorus loadings from manure to soil and water resources. Third, the quality of water resources will help set parameters for developing public policies on management of manure.
Impacts Of Cover Crops On Phosphorus And Nitrogen Loss With Surface Runoff, Antonio Mallarino, Richard Cruse, Dan Jaynes, John Sawyer, Pablo Barbieri
Impacts Of Cover Crops On Phosphorus And Nitrogen Loss With Surface Runoff, Antonio Mallarino, Richard Cruse, Dan Jaynes, John Sawyer, Pablo Barbieri
John E. Sawyer
Iowa research has demonstrated that cover crops can improve soil productivity and water quality by increasing soil organic matter and reducing nitrate nitrogen (N) leaching. Other research has investigated and is investigating the agronomic and economic viability of using cereal rye cover crops in continuous corn or corn-soybean rotations. However, no Iowa research has evaluated under natural rainfall the impact of cover crops on phosphorus (P) and N loss with surface runoff interacting with other management practices. The need for this type of research was indicated in the Iowa Nutrient Reduction Strategy documents. This effort assessed what would be needed …
Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Josh Sievers
Impact Of 4r Management On Crop Production And Nitrate-Nitrogen Loss In Tile Drainage, Matthew Helmers, John Sawyer, Josh Sievers
John E. Sawyer
Corn Belt corn and soybean producers are increasingly challenged to maximize crop production while addressing the contributions farm practices make to Gulf hypoxia. Based on the need for nitrate-N reductions to meet water quality goals, new management practices are needed to reduce nitrate-N losses at minimal cost and maximum economic benefits. This three-year field research and demonstration project is evaluating various promising N management methods and technologies by documenting the nitrate-N export and crop yield from various systems.
Isu Extension And Outreach Offers Soil Fertility Short Course, John E. Sawyer, Brent A. Pringnitz
Isu Extension And Outreach Offers Soil Fertility Short Course, John E. Sawyer, Brent A. Pringnitz
John E. Sawyer
Making sound soil fertility management decisions is an important part of successful crop production, on both an economic and environmental level. Iowa State University Extension and Outreach will offer a two-day short course focusing on principles of soils, soil fertility and nutrient management to help crop production professionals make better decisions. Highlights include sampling and testing; pH and liming; essential, secondary and micronutrients; nitrogen dynamics; manure management; and more. The small class size allows for increased discussion and interaction with Extension and Outreach specialists.
Valuing Immature Grain Crops As Forage, William M. Edwards, Stephen K. Barnhart
Valuing Immature Grain Crops As Forage, William M. Edwards, Stephen K. Barnhart
William Edwards
Late planted corn, soybeans and oats crops can be harvested as forages instead of for grain. Options include corn or oat silage, earlage, and oat or soybean hay. Estimating a value for these crops is made difficult by the fact there are few reported prices or significant markets in which they are bought and sold. However, there are two other general approaches to valuing grain crops harvested as forage. Both are based on comparisons to alternative actions by either the forage buyer or seller.
Valuing Immature Grain Crops As Forage, William M. Edwards, Stephen K. Barnhart
Valuing Immature Grain Crops As Forage, William M. Edwards, Stephen K. Barnhart
William Edwards
Late planted corn, soybeans and oats crops can be harvested as forages instead of for grain. Options include corn or oat silage, earlage, and oat or soybean hay. Estimating a value for these crops is made difficult by the fact there are few reported prices or significant markets in which they are bought and sold. However, there are two other general approaches to valuing grain crops harvested as forage. Both are based on comparisons to alternative actions by either the forage buyer or seller.
Valuing Immature Grain Crops As Forage, William M. Edwards, Stephen K. Barnhart
Valuing Immature Grain Crops As Forage, William M. Edwards, Stephen K. Barnhart
William Edwards
Late planted corn, soybeans and oats crops can be harvested as forages instead of for grain. Options include corn or oat silage, earlage, and oat or soybean hay. Estimating a value for these crops is made difficult by the fact there are few reported prices or significant markets in which they are bought and sold. However, there are two other general approaches to valuing grain crops harvested as forage. Both are based on comparisons to alternative actions by either the forage buyer or seller.