Cost-Benefit Analysis of Multi-Species Cover Crop Mixtures Used for Supplemental Forage.

While typically thought of in terms of soil conservation, cover crops have the potential to produce excellent quality forage which can be grazed in the fall to extend the grazing season, and offset pasture resources. Utilizing cover crops as supplemental forage can be a great approach to recovering costs associated with establishment and management. A study was conducted to examine the potential forage biomass and nutritive quality of a mixed species cover crop. In August 2014 and 2015, sixteen treatments were drill seeded at the Southeast Kansas Research Station near Columbus, Kansas.  Each treatment consisted of a three-way mix representing cover crops from the plant families Brassicaceae, Poaceae, and Fabaceae.  Eight species were planted, Forage radish (Raphanus sativus), Purple top turnip (Brassica rapa), Oat (Avena sativa), Rye (Secale cereale), Barley (Hordeum vulgare), Wheat (Triticum aestivium), Austrian winter pea (Pisum sativum subsp. arvense), and Berseem clover (Trifolium alexandrinum).  Biomass samples were collected at 45, 74 and 91 day intervals and evaluated to determine biomass, species composition, and forage quality parameters. Forage quality analyses indicate that all mixes were of excellent forage value, therefore, the economic analysis evaluated the biomass produced with respect to the cost of the seed. Treatment 14 (rye, radish, winter pea) was the most expensive to plant at $29.67/acre and yielded 110 kg/ha^-1 dry matter biomass per dollar spent with an average dry matter biomass of 3,252 kg/ha^-1. Treatment 8 (oat, turnip, winter pea) was the least expensive to plant at $21.44/acre and yielded the greatest biomass among treatments with 192 kg/ha^-1 dry matter biomass per dollar spent and an average dry matter biomass of 4,121 kg/ha^-1.