Alfalfa - Ecology

Ecology

Alfalfa is a perennial forage legume which normally lives 4–8 years, but can live more than twenty years, depending on variety and climate. The plant grows to a height of up to 1 meter (3 ft), and has a deep root system, sometimes stretching more than 15 meters (49 ft). This makes it very resilient, especially to droughts. It has a tetraploid genome.

Alfalfa is a small seeded crop, and has a slowly-growing seedling, but after several months of establishment, forms a tough 'crown' at the top of the root system. This crown contains many shoot buds that enables alfalfa to re-grow many times after being grazed or harvested.

This plant exhibits autotoxicity, which means it is difficult for alfalfa seed to grow in existing stands of alfalfa. Therefore, it is recommended that alfalfa fields be rotated with other species (for example, corn or wheat) before reseeding.