Plant · P-026

Alfalfa

Medicago sativa

Alfalfa is a deep-rooted perennial legume grown worldwide as one of the richest forage crops available, its taproot running six metres or more into the ground to pull up water and nutrients nothing else nearby can reach. It fixes its own nitrogen through a partnership with soil bacteria and shares some of it with neighbouring plants, and a stand can be cut two to five times a season for years once established. Cattle grazing it need their time limited, since the same richness that makes it excellent forage also causes bloat. It fails on acid or waterlogged ground and needs a season's break before it can be replanted into itself, since its own root and leaf residues suppress the next generation of its seedlings.