Aspen

Aspen

American aspens, Populus tremuloides.

Aspen is a common name for certain tree species; some, but not all, are classified by botanists in the section Populus, of the poplar genus.[1]

Contents

  • Species 1
  • Habitat and longevity 2
  • Uses 3
  • See also 4
  • References 5
  • Further reading 6
  • External links 7

Species

These species are called aspens:

Habitat and longevity

The aspens are all native to cold regions with cool summers, in the north of the Northern Hemisphere, extending south at high altitudes in the mountains. They are all medium-sized deciduous trees reaching 15–30 m (49–98 ft) tall.

All of the aspens typically grow in large oldest living colony of aspens. Some aspen colonies become very large with time, spreading about 1 m (3.3 ft) per year, eventually covering many hectares. They are able to survive forest fires, because the roots are below the heat of the fire, with new sprouts growing after the fire burns out.

Aspens do not thrive in the shade, and it is difficult for seedlings to grow in an already mature aspen stand. Fire indirectly benefits aspen trees, since it allows the saplings to flourish in open sunlight in the burned landscape. Lately, aspens have an increased popularity in forestry, mostly because of their fast growth rate and ability to regenerate from sprouts, making the reforestation after harvesting much cheaper, since no planting or sowing is required.

In contrast with many trees, aspen bark is base-rich, meaning aspens are important hosts for bryophytes[3] and act as food plants for the larvae of butterfly (Lepidoptera) species—see List of Lepidoptera that feed on poplars.

Young aspen bark is an important seasonal forage for the European hare and other animals in early spring. Aspen is also a tree of choice of the European beaver.

Uses

Aspen wood is white and soft, but fairly strong, and has low flammability. It has a number of uses, notably for making matches and paper where its low flammability makes it safer to use than most other woods. Shredded aspen wood is used for packing and stuffing, sometimes called excelsior (wood wool). It is also a popular animal bedding, since it lacks the phenols associated with pine and juniper, which are thought to cause respiratory system ailments in some animals. Heat-treated aspen is a popular material for the interiors of a sauna. While standing trees sometimes tend to rot from the heart outward, the dry timber weathers very well, becoming silvery-grey and resistant to rotting and warping, and has traditionally been used for rural construction in the northwestern regions of Russia (especially for roofing, in the form of thin slats).

See also

References

  1. ^ spp."Populus"technology transfer fact sheet: . Forest Products Laboratory: R&D USDA. Madison, Wisconsin: United States Department of Agriculture Forest Service. Retrieved 20 September 2010. 
  2. ^ Quaking Aspen by the Bryce Canyon National Park Service
  3. ^ The Biodiversity and Management of Aspen woodlands: Proceedings of a one-day conference held in Kingussie, Scotland, on 25th May 2001

Further reading

  • Fox, Mark, Linda E. Tackaberry, Pascal Drouin, Yves Bergeron, Robert L. Bradley, Hughes B. Massicotte, and Han Chen (2013). "Microbial community structure of soils under four productivity classes of aspen forests in Northern British Columbia", Ecoscience 20(3):264-275 DOI:10.2980/20-3-3611

External links

  • Aspen Information Resource, U.K.
  • Quaking Aspen Forests of the Colorado Plateau
  • Bioimages: Populus grandidentata bigtooth aspen
  • Aspen Research Bibliography