Annual herb, the whole plant is hairless. The stems lie horizontally, spreading on the ground, and the branches are light green or light red. Leaves alternate, flat, thick, horse-toothed, dark green on the top and light green or reddish on the bottom; The petiole is thick and short. Flowers sessile, flowering at noon; Leafy bracts; Sepals green, helmet-shaped; Petals yellow, obovate; Stamens and anthers yellow; Ovary glabrous. Capsule ovoid; The seeds are small, oblique spherical, dark brown and shiny. The flowering period is from May to August, and the fruiting period is from June to September.
It is produced all over China. Love fertile soil, drought and waterlogging tolerance, strong vitality. It is born in vegetable garden, farmland and roadside, and is a common weed in the field. Widely distributed in temperate and tropical regions of the world. The whole herb is used as medicine, which has the functions of clearing heat, promoting diuresis, detoxicating, reducing swelling, diminishing inflammation, quenching thirst and diuresis. The seeds are bright; Can also be used as veterinary drugs and pesticides; Tender stems and leaves can be used as vegetables, taste sour and are also good feed.