The legume family is probably the third largest of the vascular plants. Orchid and grass families are larger. However, economically, legumes are second only to grasses in importance because of their extensive use as forages. While only about 40 legumes are significant in forage production, there are 12,000-18,000 species.

mixture of grass and legume growing together
Legume-grass mixture

Although grass is the mainstay of livestock, wildlife, and humans, legumes can provide high-quality feed for each group. Forage legumes, such as alfalfa, clovers, and trefoils are generally of high quality, and their digestibility declines less rapidly as the plant matures than that of many perennial grasses. Utilizing grasses when yield and quality are balanced is very important. Later harvest or grazing will reap more yield but digestibility and palatability fall rapidly. Legumes have a longer window for best utilization, so they fit well into a feed calendar. Legumes also generally have higher levels of protein than grasses. But legumes require more management than grasses because they are more sensitive to fertility and edaphic (soil) factors. Legumes and grasses can be mixed together to take advantage of their strengths but since they have different characteristics mixtures must be more carefully managed.

The basic premise of forage-livestock managers is to utilize their land so that it can produce high-quality, high-yielding feed for as long as possible for the least amount of money or damage to the environment. This principal portends less feed will need to be bought and brought to the the farm if proper forage selection and management are practiced. Historically though, farmers have not always seen the need to manage the forages for their livestock. Grain has been cheap enough at times to allow farmers to overlook the sustainability of the plant-animal-soil continuum on their own farms or ranches. But besides the financial considerations, forage-livestock systems should consider the ways legumes interact in a sustainable environment. Like grass, legumes give back to the environment and when properly managaed can provide many additional benefits like natural self fertilization.

Grass has been more frequently utilized for conservation, environmental, and beautification purposes. This is due, in part, to grass' extensive root systems. But legumes can be used for these concerns. Many recreational facilities and conservaton efforts utilize white and subterranean clovers. Landscapers often use legumes as ground covers so that the legumes will fix nitrogen and renew the soil.

Forage managers must learn to utilize grasses and legumes for maximum quality and yield.