Impact of legume cover crops on phosphorus and nitrogen availability, weed control, and cash crop performance in reduced-tillage organic cropping systems

(Butler)

Low plant availability of soil P can be a limiting factor for organic producers in the southeast. While some reports of increased P availability following certain cool-season legume cover crops (partially due to organic acids in legume root exudates) are promising, there is limited field research on this issue to guide organic production recommendations. Similarly, more research is needed on the impact of legume cover crops on nitrogen availability, weed control, and cash crop performance in reduced-tillage organic grain production systems in the southeast. Our objectives are to (1) evaluate impact of various cool-season legume cover crops (crimson clover, hairy vetch, common vetch, white lupin, and winter pea) on P and N availability to cash crops in reduced-tillage organic systems, (2) demonstrate alternative, low-input organic summer grain crops grain sorghum and grain-type pearl millet.