Willow, also known as tunnel flowers and trees, radish silk flowers, tea trees, black gold, meliaceae, willow. Deciduous trees, the height of which can reach more than 10m, with thick branches and a broad oval crown. The bark is gray, the bark of big branches often peels off like paper, and the branchlets just start to have hair. Leaves ovoid to obovate-elliptic, 3 ~10 cm long, obtuse or slightly concave at the end, entire,

There are fine serrations on young branches and budding branches, and dense hairs on leaf axils and petioles. The flowers are white, dioecious, and the cymes are terminal. Drupe oval, blue and black. The flowering period is May-June, and the fruit maturity is 9-65438+1October. Widely distributed in the northeast, northwest to east China, south China and long river basins, naturally distributed in sunny slopes and valleys at an altitude of 200 ~ 3000 m, and also distributed in Korea and Japan.