188-4 Soybean and Corn Growth As Influenced by Methods for Controlling Previous Cover Crop, Including Winter Kill, Flaming, Disking, and Crimping.



Tuesday, October 18, 2011
Henry Gonzalez Convention Center, Hall C, Street Level

David Glett1, Charles Shapiro2, Stevan Knezevic2, Elizabeth Sarno2, Michael Mainz2 and Lynn Junck2, (1)University of Nebraska-Lincoln, Lincoln, NE
(2)Agronomy & Horticulture, University of Nebraska-Lincoln, Lincoln, NE
Development of a more diverse crop rotation in eastern Nebraska, and reduction of tillage in organic cropping systems were two objectives that inspired this 2-year study. However, including winter wheat in a rotation presents the complication of how to prudently utilize the growing period available between winter wheat harvest (July) and winter. How to best manage the cover crop for a healthy successive row crop is also a challenge. This study focused on how over-winter cover crop species and kill method impacted the following annual warm-season row crop of either corn (Zea mays) or soybean (Glycine max). The study included a combination of cover crop species and cover crop termination techniques (winter kill, roller-crimping, disking, and flaming). After harvesting winter wheat, the following cover crops were planted: buckwheat (Fagopyrum sagitattum), berseem clover (Trifolium alexandrinum L.), spring oats (Avena sativa), soybean, sudangrass (Sorghum bicolor spp. Drummondii), winter rye (Secale cereale), hairy vetch (Vicia villosa), red-yellow clover mix (Trifolium pratense and Melilotus officinalis), triticale (Triticale hexaploide Lart.), and a no-cover control. The cover crop species that were expected to winter kill were buckwheat, berseem clover, spring oats, soybean, and sudangrass; species not expected to winter kill were winter rye, hairy vetch, red-yellow clover mix, triticale, and no cover. The cover crop species not winter-killed were controlled in spring prior to row crop planting using flaming, roller-crimping, or disk tillage. The winter kill and spring disk treatments produced the highest average yields in corn and soybean, at 6.83 Mg/ha (corn) and 2.66 Mg/ha (soybean). The roller-crimper and flaming treatments both reduced yields by 68% and 62% in corn, and by 36% and 27% in soybeans, respectively. Differences in weed control and crop population were the apparent causes of the yield reductions.
See more from this Division: ASA Section: Agronomic Production Systems
See more from this Session: Organic Management Systems Community: II (Includes Graduate Student Competition)