Populus tomentosa Seeds | Chinese White Poplar
LATIN NAME: Populus tomentosa
COMMON NAME: Chinese White Poplar
Plant Profile
Populus tomentosa is a fast-growing poplar of the North China Plain, reaching twenty-five metres with a straight trunk and a broad crown. The young leaves are covered in white down, which gives the tree its Chinese name, mao bai yang, and its English one, Chinese white poplar.
It is dioecious: male and female flowers are on separate trees, in dangling catkins that open before the leaves in March. The female trees release the white cotton that drifts through northern cities in late spring and fills the gutters. The bark is smooth and grey-green on young wood, becoming furrowed and dark at the base with age.
Science & Biotechnology
The species is a natural hybrid lineage within the Populus section Populus, and it is one of the parents of many Chinese plantation hybrids. Its value in forestry is growth rate: a well-sited tree can put on two metres a year for the first decade.
Like other poplars and willows, it contains salicin and related phenolic glycosides in the bark, the compounds that gave aspirin its starting point. The wood is light, pale and short-fibred, which suits pulp and plywood but not structural timber. The wood dries quickly and warps less than most fast-grown timber, which suits plywood cores. The species is also planted to stabilise riverbanks, where its roots hold soil through spring floods, though the same roots can crack concrete if planted too close.
Uses & Benefits
The tree is planted for pulp, for plywood, for match stock and as a shelterbelt along fields and roads. In northern China it is one of the main species in the Three North shelterbelt programme, where its tolerance of poor, dry and slightly saline soil matters more than its timber.
In the garden it is a liability as much as an asset: roots seek drains and foundations, the cotton is messy, and the wood is brittle in wind. Where it is planted, it should be well away from buildings and pruned young to establish a single leader. The catkins are also collected in some places as a vegetable, though the practice is local and small in scale.
Growing from Seed
Seed is viable for only a few days and is not a practical route. Poplars are raised from hardwood cuttings: take twenty-centimetre lengths of one-year-old wood in late winter, bury two-thirds in moist soil, and roots form within a month.
The tree grows on almost any soil, including compacted and slightly saline ground, and it tolerates flooding in winter. Spacing for timber is four by four metres, with thinning at ten years. Pollen from male trees is a significant allergen in northern cities, which is why some municipal plantings now specify female clones. Cuttings struck in a nursery bed are lifted bare-root at one year and planted out in winter.
Our Take
A working tree rather than a garden one: superb for pulp and shelter, poor company for drains, paving and anyone with hay fever.
Related Reading
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