Walnuts are widely used in Asia and Europe. Walnut is mainly cultivated in North China, Northwest China and Central China in China, and Siberia in Russia. Belongs to deciduous trees. Asia is the birthplace of walnuts, and some scholars believe that walnuts originated in China.
It is reported that the Greeks brought walnut trees to Italy and transplanted them all over Europe. In 1 th century, the Romans introduced walnut trees to Britain. Walnut is used in furniture, cabinets and handicrafts. Walnut heartwood is usually light brown to brown, and the color and stripes usually change with different producing areas. Walnut is usually grayish brown with obvious dark or black stripes, and its color will fade with time.