Submitted to: Agronomy Abstracts
Publication Type: Abstract only
Publication Acceptance Date: 8/1/2004
Publication Date: 11/1/2004
Citation: Francis, D.D., Shanahan, J.F., Schepers, J.S. 2004. Water quality implications of relay-cropping in nebraska. Agronomy Abstracts #5367. Interpretive Summary:
Technical Abstract: In order to maximize yields and seed quality, seed corn producers typically apply as much or more N as is used in commercial corn production, but yields are generally less than ½ of commercial corn. This results in high residual soil N after seed corn production. The goal of this study is to determine if we can use winter wheat as a scavenger crop to utilize residual soil N after seed corn production and then inter-seed soybeans into the wheat to prepare the field for seed corn the following year. Two rows (25 cm row spacing) of winter wheat was planted in the furrows between the old 76 cm corn rows after seed corn harvest. In the spring, approximately 30 days before wheat harvest, soybeans were inter-seeded into the wheat in the 50 cm openings that were left centered over the old corn rows. Average wheat yields for the 65 ha fields have ranged between 3.7 and 5.7 Mg/ha for the past three years while the yield reduction of the inter-seeded soybean compared to mono-cropped soybean has averaged 15% for the first two years of the study. These results indicate that growing three crops in two years under the conditions and practices found in central Nebraska can reduce the potential for nitrate leaching, increase profitability for producers, and produce extra crop residue which should help in C sequestration.