Improving soybean performance in the Northern Great Plains through the use of cover crops

Cover Crops are capable of providing "multiple services" for improving soil quality and enhancing annual crop growth. Maintaining continuous plant cover on agricultural fields through the adoption of cover crops is of great interest to improve nutrient cycling, prevent soil degradation and allow further adoption of no-till farming systems. A field study was conducted in eastern South Dakota in 2007, 2008 and 2009 to evaluate four cover crop combinations (no cover, buckwheat (BUCK) (Fagopyrum esculentum Moench) + slender wheatgrass (Agropyron caninum L.) (SLDWHT), oilseed radish (Raphanus sativus L.) (RAD) + SLDWHT, turnips (Brassica rapa L.) (TURN) + SLDWHT) sown after oats (Avena sativa L.) within no-tillage (NT) and conventional tillage (CT) soil environments to investigate the potential of improving the following years soybean [Glycine max (L.) Merr.] crop performance. Soybean plant biomass, seed harvest index, yield, total nitrogen, (N) oil concentration and test weight were measured. Cover crops preceding soybeans did not negatively impact most measured plant parameters. Seed yield was increased by the RAD + SLD WHT and TURN+ SLD WHT combinations in 2008 while in 2007 and 2009 no yield increase or slight yield decrease was shown by the cover crops. Soil management and planting population had a strong influence on seed yield and seed quality in all three study years.