Extension by Anowar Islam

Species and cultivar selection and appropriate balance of grass-legume mixtures affect production and quality for the life of the pasture stand. No doubt that grass-legume mixture requires a high level of attention and management practices. However, there are many advantages of grass-legume mixtures over the monoculture, or pure stand, practices.
    Benefits from grass-legume mixtures include reduced nitrogen fertilizer requirements because legumes fix atmospheric nitrogen; increased protein and digestibility; extended grazing periods; more competitive ability against weeds; and better protection against plant heaving, cold injury and soil erosion because of better coverage. Additionally, mixtures are as easy to cure as hay; are tolerant of a wide range of soil conditions; result in reduced bloat potential when mixtures contain 40 percent or more grass; have reduced nitrate poisoning and grass tetany potential when mixtures contain 40 percent or more legumes; and have reduced lodging potential for legumes.
    To accomplish the above-mentioned benefits from grass-legume mixtures, some basic principles need to be followed.         First, keep the mixture simple. One grass and one legume in the mixture is often sufficient and more than four species mixture is not generally recommended.
    For compatible and most adaptive species, mixtures should contain similar and compatible growth characteristics and most importantly, are adaptive to the mixture of intended use. Most vigorous and rapid growth species may take over the others.
    It is also important to look at similar maturity date and palatability. Mixture species should have similar maturity dates and palatability. Different maturity dates and palatability will create many areas that will not be grazed by grazing animals and eventually will be dominated by unpalatable species.
    Additionally, high quality and pure seed selection is important. The latest cultivars have better agronomic characteristics with superior pest resistance ability and thus justify their use over the older cultivars. However, most adaptive cultivars are recommended to use. Local and regional variety test results are useful in selecting superior and adaptive cultivars and species.
    Anowar Islam is an assistant professor and the University of Wyoming Extension Forage Agroecologist in the Department of Plant Sciences in the College of Agriculture and Natural Resources. He can be reached at 307-766-4151 or mislam@uwyo.edu.