40 minutes.

Chestnuts, also known as chestnuts, chestnuts, chestnuts, etc., belonging to the chestnut family chestnut economic plants, originating in China, China is one of the earliest domesticated use of fruit trees. Chestnut cultivation has a history of more than 3,000 years, its wider distribution, germplasm resources are very rich.

In China, in addition to Heilongjiang, Inner Mongolia, Ningxia, Qinghai, Xinjiang, Tibet, Shanghai and Hainan, are chestnut production. The distribution of chestnut plants in China has a more obvious regional, the distribution of the number of south to north is a decreasing trend, to the Qinling Mountains, the Huaihe River as the boundary, can be divided into the south and north of the two obvious natural regions.

Chestnut planting range is extremely wide, from the north latitude of 40 ° 26 'Liaoning Fengcheng, south to Hainan Island (about 18 ° 30 'north latitude); from the west to about 90 ° east longitude, east to the coast (about 124 ° east longitude), which includes 24 provinces (autonomous regions, municipalities directly under the Central Government). Outside this range, southeastern Tibet and Yunnan border also has a small amount of distribution, artificial introduction of cultivation has been extended to Inner Mongolia Ningcheng, as well as Heilongjiang Boli (latitude 45 ° 40 'north).

Chestnut cultivation across the edge of the tropical, subtropical, warm temperate and mesothermal 4 climate zones, suitable for the type of complex soil conditions. The most cultivated areas for the Yellow River Basin in northern China and the Yangtze River Basin area. Chestnut vertical distribution also spans a wide range of altitude difference of about 2770m, the lowest is Tancheng, Shandong and Jiangsu Xinyi, Shuyang and other places at an altitude of 30m or so alluvial plains; the highest for the Yunnan Wisi, an altitude of 2,800 m. According to regional differences, its varieties are mainly divided into six categories.