What do I need to know about seeding turnips into corn as a forage crop?
S.F.IowaAnswer:Forage brassicas can be successfully intercropped with corn to produce a late season grazing without decreasing corn yields. Rapes and turnips are short season crops yielding from 7000 to 8000 pounds per acre. Kale is a later maturing crop that can produce as much as 12,000 pounds per acre. Regional differences determine which crops and varieties do well. Consult your local cooperative Extension agent to obtain information on crops and varieties that do well in your area.Brassicas are very digestible for livestock. In the vegetative stage brassicas can have dry matter digestibility compositions of greater than 85%. Crude protein is high as well, where tops are often greater than 17% crude protein and roots greater than 12% protein. Fine feed for most classes of livestock, especially in the fall when nutrient requirements can be low. Brassicas are generally low in fiber; therefore it is important to watch for problems with rumen acidosis. Provide hay or other forage when grazing pure brassicas, and restrict brassicas to no more than 2/3 of diet to prevent digestive problems.Brassicas can be seeded into corn in two ways, an early season and a late season planting. No-till works best if you can get in early enough, but if broadcasting be sure to increase the seeding rate at least ?. For early season planting, sow brassicas at 2-4 pounds per acre at last cultivation (V7 to V9). This typically occurs at around 3 to 5 weeks after emergence. Later plantings are successful if broadcasted into corn at blister stage, or no later than two weeks after silking. Broadcast planting rates should be increased to 3 to 6 pounds per acre at the very least.Turnips and rutabagas will be ready to graze 70 to 90 days after seeding and will hold up well into the winter if good grazing management is employed. Kale will be ready to graze from 120 to 150 day from seeding. Strip grazing is best, as this gives daily control of defoliation and helps to control intake as well. Turnips can be grazed to the ground without damaging regrowth, but other brassicas should be grazed no lower than about 6 inches to maintain the stand late into the season.References:Bartholomew, H.M. and J.F. Underwood. No date. Brassicas for ForageAGF-020-92. Columbus, OH: Ohio State University Extension, Department of Horticulture and Crop Science. Diver, S., G. Kuepper, and P. Sullivan. 2001. Organic Sweet Corn Production. Fayetteville, AR: ATTRA – National Sustainable Agriculture Information Service.