How does alfalfa contribute to soil?
Alfalfa, Medicago sativa, is a perennial forage legume. Deep roots and nitrogen-fixing bacterial symbiosis make it agriculturally important. Its three-part leaves do not make it identical to clovers in the genus Trifolium.
Roots and biological nitrogen fixation
Suitable nodule bacteria convert atmospheric nitrogen into usable forms, supported by plant-supplied energy. This does not mean neighboring plants immediately receive free nitrogen. Decomposing residues and crop rotation can benefit later crops. Drainage and rooting depth matter. Responses to acidity, salinity, and waterlogging vary with cultivar and environment.
Cutting stage and persistence
Cutting frequency and stage balance forage quality with stand persistence. Very frequent low cutting can deplete root reserves. Deep rooting helps drought resilience but does not eliminate water requirements for high yield. Feeding depends on livestock species and forage handling rather than indiscriminate use of fresh legumes. Healthy seed, weed control, and stand-longevity planning support production.