It is not a hazelnut, but a kind of hazel plant in Corylaceae, also known as chestnut, chestnut, chestnut and so on. There are about 20 species of Corylus in the world, distributed in Asia, Europe and North America. There are 8 species and 2 varieties in China, which are distributed in northeast, north, northwest and southwest regions. Hazelnut is an excellent tree species for both fruit and wood. Its fruit is shaped like chestnut, with hard shell, fat and round kernel, rich aroma, high fat content, particularly delicious taste and long aftertaste. Therefore, it has become one of the most popular nut foods, known as the "king of nuts", and is also known as the "four major nuts" with almonds, walnuts and cashews.

Chestnut is one of the earliest cultivated fruit trees in China, with a cultivation history of about 2000 ~ 3000 years. The leaves are lanceolate or oblong, and the leaf margin is serrated. Flowers unisexual, monoecious; Male flowers are inflorescences. When it matures, the involucre splits and the chestnuts fall off. Nuts are purple-brown, yellow-brown or nearly smooth, and the flesh is yellow. Fruit contains sugar, starch, protein, fat, vitamins and minerals.

Chestnut varieties in China can be roughly divided into two categories: northern chestnut and southern chestnut. Chestnut in North China has small nuts and waxy flesh, which is suitable for frying. The famous varieties are Ming chestnut, Jian tou you chestnut and Ming Jian chestnut.

Chestnut in South China has large nuts and japonica pulp, which is suitable for vegetable use. There are nine varieties, such as Li Kui, Chestnut with shallow thorns and so on. This tree is very strong. The root system is developed with mycorrhiza. Drought-resistant and barren, suitable for mountain cultivation. Suitable for acidic soil. Multi-row sowing can also be grafted and propagated. Wood is dense, hard and moisture-proof. Branches, barks and involucres contain tannins, and tannin extracts can be extracted.

Two completely different nuts, chestnut semicircle and hazelnut, are all conical ... when you see the real thing, you will know how different they are.