Minimizing Nitrate Loss to Drainage by Optimizing N Rate and Timing for a Corn-Corn-Soybean Rotation
Study author(s): Gyles Randall, University of Minnesota, Southern Research and Outreach Center
Years of study: 2007 – 2010
Location(s): Southern Research and Outreach Center, Waseca MN
Important: for the complete report, including all tables and figures, please download using the link(s) to the right.
From the mid-80’s until the early 2000’s, 97% of the tillable acres in south-central Minnesota were planted to approximately a 50:50 corn-soybean rotation. Within the last few years many growers have converted some of their acreage to a corn-corn-soybean (C-C-S) rotation to meet the growing demand for corn from the ethanol industry as well as for livestock and export markets. With this “neW’ C-C-S rotation, knowledge gaps in yield responses, nitrate losses, and profitability exist compared to the “older” C-S rotation. Moreover, transgenic hybrids possessing pest protection traits now occupy a majority of the corn acreage. Will these transgenic hybrids require different amounts of N, resulting in different production and environmental characteristics compared to non-transgenic hybrids? The overall purpose of this study is to determine the effects of N management in a C-C-S rotation on nitrate concentration and losses in tile drainage water, corn yield, N use efficiency, remote sensing signals, and profitability.
This report contains information from the third and final year and the multi-year (2008-2010) summary of this AFREC funded project as well as the 2007-2010 summary including funding from the Minnesota Corn Growers Association.