Cover Cropping and Residue Management for Weed Suppression, Soil Fertility and Organic Crop Production
The focus of this project is the design of organic farming systems that integrate essential aspects of crop management in order to increase the crop’s competitiveness with weeds, build soil fertility, and produce high-value organic crops. These integrated systems are also expected to benefit conventional growers who see them as more sustainable alternatives to traditional rotations. In particular, the use of cover crops to suppress weed growth during the winter months, smother and suppress weed seed germination through allelopathy, and provide nutrients for growth of organic edamame soybean and corn (for meal) are being investigated.
The specific objectives are to: 1) investigate the weed suppression of crimson clover (Trifolium incarnatum L.), subterranean clover (Trifolium subterraneum L.), cereal rye (Secale cereal L.), and crimson clover/cereal rye biculture cover crops prior to the establishment of principal crops and in the subsequent vegetable soybean (Glycine max L.) and corn (Zea mays L.) crops; 2) evaluate techniques for mechanically killing cover crops as alternatives to use of herbicides; 3) investigate the reseeding capacity of crimson clover and subterranean clover left to mature in a strip crop tillage system; 4) investigate the N contribution of a cover crop biculture (crimson clover/cereal rye) in a cereal rye-vegetable soybean-crimson clover/rye biculture-corn rotation; 5) characterize N cycling in a cereal rye-vegetable soybean-crimson clover/rye biculture-corn rotation; and 6) publish results, demonstrate successful production practices to growers, produce written production guidelines, and discuss results at professional and county meetings, conferences, and field days.
Cereal rye, crimson clover, and subterraneum clover cover crops were planted in the fall of 2002. The growth of the cover crops was observed over the winter months, and percent surface cover was recorded in December, 2002, and March, 2003. The cover crops were killed in mid-May, 2003, and ‘Midori Giant’ edamame seeded with a Monosem no-till vacuum seeder on May 16th.
Impacts and Contributions/Outcomes
Weed suppression by cover crop residues will be evaluated in June and July of 2003. Edamame yields will be determined.
North Carolina State University
P.O. Box 7619
NC State University
Raleigh, NC 27695-7619
Office Phone: 9195154269