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Life Sciences Commons

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Selected Works

Crops

Agricultural Science

Publication Year

Articles 1 - 4 of 4

Full-Text Articles in Life Sciences

Crop Responses To Amisorb In The North Central Region, Sylvie Brouder, Robert Dowdy, Dave Franzen, Gary Hergert, Robert Hoeft, Maurice Horton, Keith Kelling, David Mengel, George Rehm, John Sawyer, Peter Scharf, Darryl Warnacke, David Whitney Aug 2017

Crop Responses To Amisorb In The North Central Region, Sylvie Brouder, Robert Dowdy, Dave Franzen, Gary Hergert, Robert Hoeft, Maurice Horton, Keith Kelling, David Mengel, George Rehm, John Sawyer, Peter Scharf, Darryl Warnacke, David Whitney

John E. Sawyer

Originally used to prevent scale in boilers, carpramid or thermal polyaspartate (copoly[(3-carboxypropionamide)( 2-carboxylmethyl) acetamide)] was brought to agriculture under the trade names AmiSorb and Magnet. It claimed to increase nutrient uptake through artificially increasing the volume of soil occupied by roots through increased root branching and root hair development. Under controlled hydroponic or greenhouse conditions, the use of carpramid increased nutrient uptake, some yield determining factors such as wheat tillering and in some cases, crop yield. Extensive field testing from 1996 to 1998 under various nutrient regimes, placements, forms, and timings resulted in very inconsistent performance. Averaged across all experiments …


Farm Energy: Energy Consumption For Row Crop Production, H. Mark Hanna, John E. Sawyer, Dana Petersen Jul 2016

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 Jul 2016

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.


Nitrogen Use In Iowa Corn Production, John E. Sawyer Jul 2016

Nitrogen Use In Iowa Corn Production, John E. Sawyer

John E. Sawyer

Nitrogen is essential for growth and reproduction of crops and is involved in many important plant biochemical processes. Nitrogen management is critical for optimal yields for corn production systems. This publication discusses long-term research done in Iowa and shows corn yields average about 60 bu/acre for continuous corn and 115 bu/acre for corn following soybean when corn is not fertilized. However, corn fertilized with N will easily yield 200 bu/acre or more. This means soil management and nitrogen fertilization practices, such as using economical optimum N rates, should be used to help optimize crop yields, use N efficiently, and enhance …