Mixtures of legumes and grasses usually are desired because yields tend to be greater than with either the legume or the grass alone.
Grasses will fill in where the legume ceases to grow, reduce soil erosion, reduce the late winterheaving damage, increase the drying rate, reduce the bloat hazard with ruminant animals and perhaps improve animal acceptance of the feed.
Mixtures of two or three well-chosen species are usually higher-yielding than "shotgun" mixtures of five or six species in which some of the species are not particularly well-suited to the soil, climate, or use.
Forage crop mixtures are listed in the Illinois Agronomy Handbook, published by the University of Illinois Cooperative Extension Service. Current copies of the handbook are available for $5 from your local county Extension office, or by writing to: Office of Agriculture Communications and Education, 54 Mumford Hall, 1301 W. Gregory Dr., Urbana, IL, 61801. (Make checks payable to the University of Illinois.)