Alfalfa is the general name of alfalfa, commonly known as cauliflower, which is a perennial flowering plant. One of the most famous is alfalfa as a pasture. There are many kinds of alfalfa, most of which are wild medicinal materials.

Annual or perennial herbs, sparse shrubs, no vanilla flavor. Pinnately compound leaves, alternate, stipules partially connate with petiole, entire or dentate, leaflets 3, margin usually serrated, lateral veins extending straight to the tip of teeth. Racemes axillary, sometimes capitate or solitary, with small flowers and usually pedicels; Bracts small or absent; Calyx bell-shaped or tubular, calyx teeth 5, equal in length.

Corolla yellow, purple alfalfa and other hybrids are often purple, purple-blue, brown and so on. Flag petal obovate to oblong with narrow base and often folded back. The wing flap is rectangular, and one side of the wing flap is hooked with the auricular body of the keel flap, which falls off after pollination, and the keel flap is blunt and round; The stamens are dimorphic, the tips of filaments are not enlarged, and the anthers are of the same type.

Style is short, conical or linear, both sides are slightly flat, glabrous, the top of the column, linear ovary, sessile or short stipe, ovule 1 to many. The pod is spirally twisted, kidney-shaped, sickle-shaped or nearly straight, longer than the calyx, and the back seam is often ribbed or spiny; There are seeds 1 to most. Seeds small, usually smooth, somewhat kidney-shaped, without caruncle; The base of cotyledons unearthed from seedlings is not enlarged and there is no joint.