Sichuan Walnut

Sichuan Walnut

　　Sichuan Walnut

　　Walnut, also known as common walnut, belongs to the phylum Angiosperms, class Dicotyledoneae, family Juglandaceae, and genus Juglans. In Nanjiang County, it is distributed in four major types: common walnut, iron walnut, wild walnut, and Manchurian walnut. It is widely found at altitudes ranging from 400 to 1,800 meters and is an ideal economic tree species for mid-altitude mountainous regions, being drought-resistant, thin-soil-tolerant, and averse to waterlogging and high temperatures. Nanjiang County is located at the southern foot of the Micang Mountains, bordering Tongjiang to the east, Bazhong to the south, Wangcang to the southwest, and Nanzheng in Shaanxi to the north. It lies between latitude 31°50’–32°45’ and longitude 106°27’–107°10’, featuring a long north-south stretch and a narrow east-west span. The county covers an area of 3,417 square kilometers, with a forest coverage rate of 47%. Elevations range from 370 to 2,508 meters, and the terrain consists of steep, narrow ridges and deeply incised valleys, leaving vast areas of barren hills, wasteland, and sloping farmland. The soil is mainly composed of purple soil, yellow soil, and yellow-brown soil. The climate is humid while the soil tends to be dry. The annual average temperature is 16.2°C, the frost-free period lasts 259 days, the mean annual accumulated temperature is 5,096°C, the average annual rainfall is 1,161 mm, annual sunshine hours total 1,570, and relative humidity ranges from 64% to 79%. There are 20,000 hectares of land suitable for walnut cultivation that can achieve high, stable, and premium yields, making it the most ideal region for developing the walnut industry. The introduction of walnuts in Nanjiang began in the Han Dynasty and has a history of over a thousand years. By the 1970s, the industry had already taken shape and gained fame both within and outside the province, reaching an export capacity of 400–600 tons. Currently, the county has 800,000 bearing walnut trees covering approximately 50,000 mu (about 3,333 hectares), yielding 1.5 million kilograms of walnuts with an output value of 7.5 million yuan, establishing it as a major walnut-producing county.