Populus lasiocarpa
Illustration
The big-leaf cottonwood (Populus lasiocarpa ) is a deciduous tree of the genus of the poplars in the family of pasture plants. Their natural habitat is in Central and Western China. There, it is an important source of timber.
Description
The big-leaf cottonwood is a small, up to 20 meters tall, slow growing deciduous tree with rounded crown, which can reach a diameter at breast height of 50 centimeters. The Stammborke is dark gray and furrowed. Young twigs are hairy thick and densely tomentose, they verkahlen later and then have a yellow-brown color. The buds are large, acuminate and slightly sticky. The leaves have a 5 to 10 cm long, hairy, flat, upper side red-colored stem. The leaf blade is ovate, 15 to 30 inches long and 10 to 15 inches wide, acuminate with heart- shaped base and glandular- serrated leaf edge. The upper leaf surface is bright green, at first hairy, later glabrous and has red side and central nerves. The underside is very hairy on the nerves. The flowers are dioecious distributed as with all poplars. The male catkins are 9 inches long, the male flowers have 30 to 40 stamens. The female catkins are about 15 to 24 inches long. The capsule fruits are ovoid, 1.0 to 1.7 inches long and hairy tomentose. The species flowers from March to May the fruits ripen from May to June.
Male kitten
Distribution and location
The natural range is located in the temperate zone of China in the provinces of Guizhou, Hubei, Shaanxi, Sichuan and Yunnan. Where it grows in biodiversity-rich, moist deciduous forests on mountain slopes and river banks at altitudes 1300-3500 meters on fresh to moist, good, mostly loamy, slightly acidic to alkaline soils in sunny locations. The species is thermophilic and usually frost hardy.
Systematics and history of research
The big-leaf cottonwood is a tree species from the section Leucoides in the genre of poplars (Populus ), family willow family ( Salicaceae ). It was first described by Daniel Oliver in 1890.
There are two varieties:
- Populus lasiocarpa var lasiocarpa 15 to 24 inches long and female catkins 1.0 to 1.7 centimeters long and short -stalked capsule fruits.
- Populus lasiocarpa var longiamenta PY Mao & PX Hey with up to 40 centimeters long and female catkins 1.6 and 1.9 centimeters in length, seated fruit. The distribution area is located in Yunnan at altitudes of 1700-1900 meters.
Use
The big-leaf poplar is an important supplier of timber in the area of distribution. In Central Europe it is used because of the attractive foliage as an ornamental tree, but forestry irrelevant.