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Full-Text Articles in Life Sciences
N Management Influences On N Losses Through Tile Lines, Gyles W. Randall, John E. Sawyer
N Management Influences On N Losses Through Tile Lines, Gyles W. Randall, John E. Sawyer
John E. Sawyer
Subsurface tile drainage from row-crop agricultural production systems has been identified as a major source of nitrate entering surface waters in the Mississippi River Basin. Tile drainage studies have been conducted on three drainage research facilities at two locations in Minnesota since 1973. Nutrient and crop management systems, including rate and time of nitrogen (N) application, N sources (fertilizer, dairy manure, and hog manure), nitrification inhibitors, cropping systems, and tillage systems have been evaluated to determine their agronomic and environmental characteristics. Results from these studies have been instrumental in the development of best management practices for nutrient management in Minnesota.
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 …
Farm Energy: Energy Consumption For Row Crop Production, H. Mark Hanna, John E. Sawyer, Dana Petersen
Farm Energy: Energy Consumption For Row Crop Production, H. Mark Hanna, John E. Sawyer, Dana Petersen
John E. Sawyer
This publication provides an overview of farm energy use related to corn and soybean production in Iowa. Three areas of row crop production--field operations, fertilizer and pesticide application, and artificial drying--are used to illustrate on-farm energy consumption.
Farm Energy: Energy Conservation In Corn Nitrogen Fertilization, John E. Sawyer, H. Mark Hanna, Dana Petersen
Farm Energy: Energy Conservation In Corn Nitrogen Fertilization, John E. Sawyer, H. Mark Hanna, Dana Petersen
John E. Sawyer
Optimum corn yields require nitrogen fertilization in most crop rotations, but the energy consumed during the production of nitrogen fertilizer is considerable. Learn more about maximizing economic, environmental, and energy returns for nitrogen and other fertilizers.
Annual Swine Manure Applications To Soybean Under Corn-Soybean Rotation, Allah Bakhsh, Rameshwar S. Kanwar, James L. Baker, John E. Sawyer, Antonio P. Mallarino
Annual Swine Manure Applications To Soybean Under Corn-Soybean Rotation, Allah Bakhsh, Rameshwar S. Kanwar, James L. Baker, John E. Sawyer, Antonio P. Mallarino
John E. Sawyer
The response of a corn-soybean rotation system receiving fall manure application to both corn and soybean is not well understood in terms of its impact on nitrate leaching to subsurface drainage water and crop yields. This field study was conducted from 2001 through 2005 with the key objective of determining the effects of manure application to both corn and soybean on NO3-N concentrations in subsurface drainage water and corn-soybean yields. The study was conducted on 0.4 ha plots instrumented with state-of-the-art subsurface drainage monitoring systems at the Iowa State University research center, Nashua, Iowa. Nitrogen application rates from liquid swine …
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.
Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart J. Birrell, David A. Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt
Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart J. Birrell, David A. Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt
Douglas L Karlen
Drought conditions in 2012 were some of the most severe in recent history. The purpose of this study is to examine the impact of drought on quality, quantity, and theoretical ethanol yield (TEY) of three bioenergy feedstocks, corn stover, mixed grasses from Conservation Reserve Program lands, and Miscanthus ×giganteus. To assess drought effects on these feedstocks, samples from 2010 (minimal to no drought) and 2012 (severe drought) were compared from multiple locations in the US. In all feedstocks, drought significantly increased extractives and reduced structural sugars and lignin; subsequently, TEYs were reduced 10–15%. Biomass yields were significantly reduced …