1, Populus, the general name of poplar in Salicaceae, originated in the northern hemisphere. Other Populus plants are distributed in higher places in the north and are famous for their swaying leaves and straight trunks. Because of the fast tillering, more trees grow into forests and rare individual trees, which is very beneficial to the natural landscape. Bark is grayish green, smooth and naturally branched; The green leaves are dense and turn bright yellow; It is dioecious, and the first leaf opens in spring. Bark is usually gray and smooth, and only the base of old trees is rough. Buds villous or smooth. Leaves villous, at least under long branches and leaves; Short branches and leaves are fluffy or smooth; Petiole lateral flat or nearly cylindrical. Bracts split into strips, with long hairs on the edges, and stigma 2-4-lobed; Stamens 5-20, anthers not apiculate. Capsule oblong, usually 2-valved. Poplar type, 1 species (1 hybrid), 13 variety, 7 varieties made in China.

2. Strong positive tree species. I like a cool and humid climate. In places where the temperature difference between day and night is relatively large in early spring, bark often freezes and cracks, commonly known as "broken belly disease". In warm, hot and rainy climate conditions, diseases and insect pests are prone to occur, resulting in poor growth. The requirements for soil are not strict, and it grows rapidly on deep, fertile and moist loam or sandy loam. In arid and barren saline-alkali land and desert land with little accumulated water, poor growth and serious pests and diseases are easy to form "small old trees" Slightly saline-alkali-tolerant, big trees are water-resistant and moisture-resistant, with deep roots, developed roots, strong rhizosphere germination, rapid growth, smoke and dust resistance and pollution resistance. Life span is the longest tree species in Populus euphratica, with a life span of 200 years.

3. It is native to China and widely distributed. It starts from southern Liaoning and Inner Mongolia in China in the north, and reaches the Yangtze River basin in the south, with the middle and lower reaches of the Yellow River as a suitable residential area. Vertical distribution is below 1200m above sea level, and most of them are born in deep soil layers in low mountain plains. There are big trees beside ditches and dams at an altitude of 1900m near Kunming, which grow well.