2, lettuce is a daisy family, lettuce genus annual or biennial herbs. Height 25-100 cm, stem erect, solitary, basal leaves and lower stem leaves large, undivided, oblanceolate, elliptic or elliptic-oblanceolate, apical acute, short acuminate or rounded, sessile, leaves on lower panicle branches and leaves on panicle branches very small, ovate-cordate, sessile. Heads numerous or very numerous, arranged in panicles at tips of stem branches. Achenes oblanceolate, compressed, light brown, apically acute into a fine beak, the beak finely filiform, several times as long as the achenes, flowering and fruiting from February to September.

The species is native to the Mediterranean coast, and is cultivated throughout China. It is a cold-hardy vegetable, preferring cooler climates, not resistant to high temperatures. Like moist. And the need for fertilizer is large, it is appropriate to grow in organic matter, water retention and fertilization of clay loam or loamy soil, reproduction mode for seeding. Cultivated varieties of lettuce, lettuce, curly lettuce.

Edible, flavorful and crisp, it is a more popular vegetable. It can stimulate the secretion of digestive enzymes, enhance appetite, promote the peristalsis of the body's intestinal wall, and prevent constipation.