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Full-Text Articles in Life Sciences
Equipment Considerations: Liquid Fertilizer, H. Mark Hanna, John E. Sawyer
Equipment Considerations: Liquid Fertilizer, H. Mark Hanna, John E. Sawyer
John E. Sawyer
A review of application equipment considerations can help ensure that your nitrogen fertilizer is properly applied. This article focuses on liquid fertilizers and is the last in a series of three articles (other two in April 9, 2001, Integrated Crop Management issue) about nitrogen fertilizer application and equipment. A primary consideration for equipment is the relatively high application volumes required. For example, a 150-lb N/acre application of 28 percent UAN solution requires an application of 50 gal/acre.
Equipment Considerations: Anhydrous Ammonia, H. Mark Hanna, John E. Sawyer
Equipment Considerations: Anhydrous Ammonia, H. Mark Hanna, John E. Sawyer
John E. Sawyer
Because of abnormal nitrogen fertilizer production, import, and supply this year and with perhaps a short spring application season, some crop producers may use a form of nitrogen fertilizer with which they are unaccustomed. A review of application equipment considerations can help ensure that your nitrogen fertilizer is properly applied. This article focuses on anhydrous ammonia and is the second in a series of three articles about nitrogen fertilizer application and equipment.
Equipment Considerations: Dry Granual Fertilizer, H. Mark Hanna, John E. Sawyer
Equipment Considerations: Dry Granual Fertilizer, H. Mark Hanna, John E. Sawyer
John E. Sawyer
A review of application equipment considerations can help ensure that your nitrogen fertilizer is properly applied. This article focuses on dry granular fertilizers and is the first in a series of three articles about nitrogen fertilizer application and equipment. Because of varying physical properties of dry fertilizer materials, it is important to consider material distribution across the swath as well as application rate.
Equipment Maintenance: Fertilizer Applicators, H. Mark Hanna, John E. Sawyer, Michael J. Tidman
Equipment Maintenance: Fertilizer Applicators, H. Mark Hanna, John E. Sawyer, Michael J. Tidman
John E. Sawyer
Winter is a good time for crop producers and fertilizer dealers to work out the kinks in fertilizer application equipment for economic, environmental, efficiency, and safety reasons. Properly working application equipment translates into getting the most out of every fertilizer dollar. Overapplying to compensate for poorly calibrated equipment wastes money and could mean nutrient-rich runoff and consequently, a potential water quality problem. This article provides some tips for maintaining your fertilizer application equipment.
Fertilizer And Swine Manure Management Systems: Impacts On Agronomic And Environmental Soil Phosphorus Tests And On Phosphorus Loss With Subsurface Drainage, Antonio P. Mallarino, John E. Sawyer, Jeremy Klatt, Rameshwar S. Kanwar, Carl H. Pederson, James L. Baker, Kenneth T. Pecinovsky
Fertilizer And Swine Manure Management Systems: Impacts On Agronomic And Environmental Soil Phosphorus Tests And On Phosphorus Loss With Subsurface Drainage, Antonio P. Mallarino, John E. Sawyer, Jeremy Klatt, Rameshwar S. Kanwar, Carl H. Pederson, James L. Baker, Kenneth T. Pecinovsky
John E. Sawyer
Manure or fertilizer can be used to supply the phosphorus (P) needs of crops. However, excess P application increases the risk of P loss from fields and of water quality impairment through increased algae growth. Poor water quality in many Iowa lakes has prompted questions about the impact of P management practices on P loss from fields and the effectiveness of using agronomic soil tests for environmental purposes.
Fertilizer And Swine Manure Management Systems: Impacts On Crop Production And Nitrate-Nitrogen Leaching With Subsurface Drainage, Rameshwar S. Kanwar, Carl H. Pederson, James L. Baker, Antonio P. Mallarino, John E. Sawyer, Kenneth T. Pecinovsky
Fertilizer And Swine Manure Management Systems: Impacts On Crop Production And Nitrate-Nitrogen Leaching With Subsurface Drainage, Rameshwar S. Kanwar, Carl H. Pederson, James L. Baker, Antonio P. Mallarino, John E. Sawyer, Kenneth T. Pecinovsky
John E. Sawyer
Nutrient losses from row-crop land can cause nonpoint source water quality problems and “impaired waters.” Nitrogen (N) losses due to nitrate (NO3) leaching cause drinking water problems and possibly increase hypoxia (low oxygen) problems in the Gulf of Mexico. Phosphorus (P) losses can cause eutrophication problems in surface waters (lakes, streams, and reservoirs) in Iowa where algal blooms decrease oxygen, kill fish, and result in murky and bad tasting water. The U.S. EPA and the Iowa Department of Natural Resources are developing nutrient criteria/standards and implementation plans to address TMDL’s (Total Maximum Daily Load) and to improve the quality of …
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.
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.
Evaluation Of Tillage And Crop Rotation Effects On Groundwater Quality—Nashua Project, Rameshwar S. Kanwar, Douglas Karlen, Thomas S. Colvin, William W. Simpkins, Vince J. Mcfadden
Evaluation Of Tillage And Crop Rotation Effects On Groundwater Quality—Nashua Project, Rameshwar S. Kanwar, Douglas Karlen, Thomas S. Colvin, William W. Simpkins, Vince J. Mcfadden
Douglas L Karlen
Sampling shows that agricultural chemicals are occurring increasingly in ground- and surface water in Iowa. The same trend has been reported throughout the United States; one study reported finding 73 pesticides in the groundwater of 34 states. Even pesticides known to be adsorbed to soil particles (and thus relatively immobile) have been found in a few sampled wells in trace concentrations. Nitrate-nitrogen (NO3-N) is the most common agricultural chemical found in groundwater. Nitrogen fertilizers and pesticides applied to the soil surface prior to and immediately following crop planting are particularly susceptible to surface runoff or leaching to groundwater through the …