There are about 100 species in the whole genus and 62 species (including 6 hybrids) in China, among which 57 species are distributed in China and 4 species are introduced and cultivated. In addition, there are many varieties, forms and introduced strains.
The classification system of Populus is divided into five schools: Takamahaka School, Poplar School, Black Poplar School, Turanga School and Poplar School.
Mainly distributed in Central China, North China, Northwest China, Northeast China and other vast areas.
Trees. Trunk usually ends straight; Bark is smooth or longitudinally dehiscent, usually grayish white. There are terminal buds (Populus euphratica has no buds), and the bud scales are mostly sticky. Branches are long (including sprouted branches) and short, cylindrical or ridged. Leaves alternate, mostly ovoid, ovoid-lanceolate or triangular-ovoid, and often have different shapes and toothed edges on different branches (such as long branches, short branches and sprouting branches); Petiole long, lateral flat or cylindrical,
Apex with or without glandular points.
Inflorescence droops and leaves often open first; Male inflorescence opens earlier than female inflorescence; Bract apex acute or dehiscent, membranous, caducous, disk tilted cup-shaped; Male flowers have 4-4 stamens, inserted in the disk, dark red anthers, short filaments, free; Ovary style short, stigma 2-4-lobed. Capsule 2-4(5) cracked. The seeds are small and numerous, and the cotyledons are oval.
The industrial utilization of poplar mainly includes: large-diameter poplar is mainly used to produce plywood, laminated veneer lumber and furniture; Small-diameter poplar is used to produce fiberboard, particleboard, paper making and matches.
Generally, large plant spacing is used for planting. In developing countries, close planting is the main method, and the rotation period is short, producing medium-diameter wood for civilian use. There are some transitional types between the two.
Poplar can be widely used in ecological protection forest, three-north protection forest, agriculture and forestry protection forest and industrial timber forest. Poplar is an excellent tree species for road greening and landscape. Its characteristics are tall and majestic, neatly marked, fast forest formation, sandstorm prevention and waste gas absorption.