Benefits of using forage legumes
Forage legumes can obtain their nitrogen (N) requirements through a symbiotic association with Rhizobium (and other related genera) bacteria. This biologically “fixed” N becomes available to companion or post-season crops through plant decomposition and recycling of N from animal wastes. The use of clover and other legumes is a key component of sustainable agriculture and reduces our dependence on fossil resources. Forage legumes are useful in agricultural production systems through their ability to symbiotically fix atmospheric nitrogen and:
a) produce high quality forage;
b) improve animal performance compared to grass monocultures;
c) enhance seasonal distribution of forage production to complement warm-season perennial grasses; and
d) reduce the risk of groundwater contamination when used as an alternative to nitrogen fertilizer.
Types of forage legumes
Forage legume species are divided into annuals, perennials and biennials, and each of these categories is further divided into cool- and warm-season forages. Annuals germinate, grow, and mature in one growing season and therefore must be established from seed each year. Perennials have the ability to live more than one year under appropriate climatic conditions. They usually go dormant sometime during the year and then initiate new growth from roots, crowns, rhizomes, or stolons. Biennials require two growing seasons to complete their life cycle with the first season devoted to vegetative growth and flowering occurring in the second season. Warm-season annual forages begin growth in the spring and often die in the autumn with the first killing frost. Cool-season annual forages generally begin growth in autumn and develop mature seed in late spring or early summer.