Author
BIERMAN, PETER - University Of Minnesota | |
ROSEN, CARL - University Of Minnesota | |
Venterea, Rodney - Rod | |
LAMB, JOHN - University Of Minnesota |
Submitted to: Agricultural Systems
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/22/2012 Publication Date: 6/1/2012 Citation: Bierman, P., Rosen, C., Venterea, R.T., Lamb, J. 2012. Survey of nitrogen fertilizer use on corn in Minnesota. Agricultural Systems. 109(1):43-52. Interpretive Summary: Corn production consumes approximately 40% of all nitrogen (N) fertilizers applied to agricultural crops in the U.S. and is a dominant cropping system in the upper midwest U.S. including in the state of Minnesota. As part of an integrated research, extension, and education grant from the U.S. Department of Agriculture, a survey was conducted in collaboration with University of Minnesota Extension, the Minnesota Department of Agriculture, and the National Agricultural Statistics Survey to characterize the use of N fertilizer on corn by Minnesota farmers. Information was gathered from approximately 1500 farmers distributed across all of the corn growing regions in the state regarding details of their N management activities including fertilizer application rates, timing, chemical forms, use of additives, starter fertilizers, irrigation, and other practices. This survey provides the most comprehensive set of data on N fertilizer use on corn that has been collected in Minnesota. The statewide average N fertilizer rate was 157 kg N ha-1. Variable rate application was used to apply N by 23% of farmers. About 59% of surveyed farmers applied the majority of their N fertilizer in the spring before planting, 32.5% made their main N application in the fall, and 9% sidedressed the majority of their N after corn emergence. Most farmers used anhydrous ammonia (46%) or urea (45%) as their major source of N fertilizer. About 6.5% used a liquid N fertilizer as their primary N source. Overall results indicate that N fertilizer use by Minnesota corn farmers is generally consistent with University of Minnesota Extension N management guidelines. Nitrogen use efficiency (NUE ) could probably be improved by taking adequate N credit for previous soybean crops. In the South Central region of the state, NUE could potentially be improved by increased use of nitrification inhibitors with fall-applied anhydrous ammonia or by delaying anhydrous ammonia application until spring. This kind of information can be used by scientists, regulators, and extension personnel to target research and education programs to improve N management for both production and environmental goals. Technical Abstract: A survey was conducted in the spring of 2010 to characterize the use of N fertilizer on corn (Zea mays L.) by Minnesota farmers in the 2009 growing season. Detailed information on N fertilizer management practices was collected from interviews with 1496 farmers distributed across all of the corn growing regions in the state. The total amount of corn they grew represented 6.8% of the ha of corn harvested in Minnesota in 2009. This report summarizes data on: 1) N fertilizer rates, 2) Major N sources, 3) Application timing of the major N source, 4) Use of nitrification inhibitors, additives, and specialty N fertilizer formulations, 5) Fertilizer placement and incorporation practices, 6) Use of starter fertilizer, split and sidedress applications, and other N sources such as ammonium phosphates, 7) N fertilization of irrigated corn, and 8) Use of soil testing as a fertility management tool. Many of the survey results are reported as statewide averages, but where regional differences occurred the data are broken down and presented separately for different parts of the state. This survey provides the most comprehensive set of data on N fertilizer use on corn that has been collected in Minnesota. The information can be used to target research and education programs to improve N management for both production and environmental goals. The statewide average N fertilizer rate was 157 kg N ha-1. Variable rate application was used to apply N by 23% of farmers. About 59% of surveyed farmers applied the majority of their N fertilizer in the spring before planting, 32.5% made their main N application in the fall, and 9% sidedressed the majority of their N after corn emergence. Most farmers used anhydrous ammonia (46%) or urea (45%) as their major source of N fertilizer. About 6.5% used a liquid N fertilizer as their primary N source. Overall results indicate that N fertilizer use by Minnesota corn farmers is generally consistent with University of Minnesota Extension N management guidelines. Nitrogen use efficiency (NUE ) could probably be improved by taking adequate N credit for previous soybean crops. In the South Central region of the state, NUE could potentially be improved by increased use of nitrification inhibitors with fall-applied anhydrous ammonia or by delaying anhydrous ammonia application until spring. |