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.
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.