It has something to do with temperature. Catkins begin to fall in spring. After winter dormancy, the fruit cracks when it matures (poplar fruit: I cracked _' _'). Flying catkins are only found in female trees, and they are fruits. Poplar fruits crack when they are ripe, and the seeds inside are emitted. Specifically, it is the Mao Mao of poplar, that is, the temperature of poplar catkins rises, the fruit matures, and the hair inside comes out. If you look closely at Mao Mao, you will find something hard below, which is actually a seed. Mao Mao is equivalent to gliding, sending seeds to the right place to take root and sprout by wind.

Poplar (Latin scientific name: PopulusL. ) is a poplar plant of Salicaceae. The classification system of poplar is divided into five schools: Populus cathayensis, Populus cathayensis, Populus nigra, Populus euphratica and Populus macrophylla. Its trunk is usually straight, its bark is smooth or longitudinal, often gray, with many bud scales, alternate leaves and toothed edges; Petiole long, lateral flat or cylindrical; _ Catkin droops, bract tips are pointed or striped, anthers are dark red, filaments are short, and ovary style is short; Capsule 2~4(5) is dehiscent, with small seeds and oval cotyledons. Poplar is a forest tree species scattered in temperate and cold temperate zones in the northern hemisphere.

Mainly distributed in Central China, North China, Northwest China, Northeast China and other vast areas. Van Gogh's first work, Poplar Near Newnan, bought by Dutch Museum, will be restored in the near future. This is Van Gogh's painting of poplars.