Hazel.

The Corylus perennional deciduous shrubs, a few of which are trees. The seeds of the dragonfly have been found in the Neolithic ruins of the village of Semipo in Shaanxi Province, China. A total of 16 species of plants have been found around the world, distributed in the cold and temper zones of the northern hemisphere. Leaves are born to each other, flowers are monolithic. Monoecious. Male flowers are □ flower sequence, cylindrical, sagging; Nuts near-spherical or egg-shaped, outsourced cleavage, barrel or needle-shaped total. The species contains 50 to 60% fat,
protein
17 to 19%, rich in nutrition, raw food, fried food, oil or make pastries and candy ingredients. There are four species in China, all wild or semi-wild. (1) C.heterophylla. Widely distributed in the Northeast, North China, Northwest low hilly areas. Cold-resistant, drought-resistant, barren and thin, can naturally develop into a forest on arid slopes, often used as a dry and cold area to green desert mountains, water and soil conservation pioneer tree species; (2) C. mandshurica. Small branches and leaves are soft hair, the total long barrel-shaped, scattered slender hedgehogs, happy wet environment. Mainly distributed in the northeast of the mountain needle wide mixed forest edge. (3) C. Chinensis. The tree is up to 40 meters high. The total length of the tube. Mainly produced in Hubei, Sichuan, Yunnan, warm and humid climate and fertile soil. (4) C. tibetica. Also known as hedgehog. Total dense by needles, nut shell thickness, low yield. It is located in the southwest and northwest.

most widely distributed in Europe is C.avellana. Fruit is large, good quality, Turkey, Italy and Spain and other countries widely cultivated after long-term selection and nearly half a century of hybrid breeding, has been selected many excellent varieties. North American-origin horned and American hazelnuts are cold-resistant and disease-resistant, and the United States and Canada, which are used as parents to interbreed with European terns, have cultivated new varieties that are short-lived, cold-resistant and fruity for a long time.