Description
Populus – Aspen – Poplar – Cottonwood –
There are about 35 species of fast growing, short lived (60 years or so) of usually dioecious, mainly deciduous tree in this genus. They occur in woodland, valley bottoms, riverbanks, and swamp lands in North temperate regions. They are grown for their very rapid growth as specimen trees, and for their variable, alternate, ovate, triangular-ovate, diamond shaped leaves, often aromatic in bud and when unfolding. They have tiny flowers borne in catkins, generally 2-6″ long, mostly in late winter or spring, before the leaves, Male and female flowers are usually borne on separate trees, the females producing copious fluffy white seed (“cotton”). Most poplars are useful as windbreaks, P, alba and P. x canescens will thrive in coastal sites. The vigorous root systems may damage drains and foundation, so avoid growing poplars within a 100′ feet of a building.
Tolerant of any, except constantly waterlogged soil, although best in deep, fertile, moist, but well drained soil in full sun.
Prone to borers, leaf miners, caterpillars, scale insects, leaf hoppers, canker, butt rot, crown gall, dieback, root rot, leaf blister, white rot, rust, and powdery mildew.
P. fremontii – Fremont Cottonwood – Alamillo – Western Cottonwood– This fast growing, round headed, deciduous tree from Western USA grows 80-100′ feet tall and 50′ feet wide. It produces toothed, glossy, pointed, yellow-green, broadly triangular leaves, to 3″ long, which turn yellow in autumn. In early spring it bears pendent red male or green female catkins, both to 4″ long. Lacks resin seen in many other poplars.
Zones 3-9
