Treesearch

The broad range of aspen in North America is evidence of its equally broad tolerance of wide variations in climate (Fowells 1965). Given open space for establishment and not too severe competition from other plants, aspen can survive from timberline on the tundra's edge to very warm temperate climates, and from the wet maritime climates of the coasts to very severe and often quite dry continental climates of the interior. Therefore, to describe the climates typical of this species' range is extremely difficult, especially in the mountainous West, where climates vary greatly. However, aspen...

Wooded draws and natural prairie woodlands occupy about 1.1 percent of the northern Great Plains. While the extent of wooded draws is extremely limited, their importance and value is much greater. These unique communities are important for wildlife and livestock habitats, soil stabilization, watershed maintenance, firewood, esthetics, and species diversity (Fig. 1). An estimate of their value has been placed at $10 million annually, primarily production of fuelwood, and wildlife habitat and hunting. However, the dominant use is cattle grazing which requires management to control overuse.

Data from wildlife habitat use, wood production, and values of hunting, trapping, and firewood reflect the contribution to values of wooded draws on the northern High Plains. Values included expenditures and net willingness to pay. Approximate values per annum derived were: deer hunting $26 million; turkey hunting $1 million; fur trapping $4 million; and firewood $7 million for a total annual value of $38 million from wooded draws.

The Daubenmire habitat type method was used to classify the upland hardwood draws of southwestern North Dakota. Preliminary data analysis indicates there are four upland habitat types: Fraxinus pennsylvanica/Prunus virginiana; F. pnnseanica-Ulmus americana/P. virginiana; Populus tremuloides/Prunus virginiana, and Quercus macrocarpa/P. virginiana.

Long-eared Owls nest at high densities locally over the Great Plains where suitable habitat is limited (Bent 1938), yet , according to Whitney et al. (1978), this species is rare to uncommon in South Dakota. Especially west of the Missouri River, few nesting records have been reported. This paper reports the occurrence of Long-eared Owls in the Badlands National Park between May 1981 and June 1983. The birds were observed by Paulson and Bob Hodorff, a Forest Service technician, during monthly, 4-day bird censuses of Rocky Mountain Juniper (Juniperus scopulorum) stands, and by Paulson alone...

In the West, aspen forests have not been actively managed for wood products largely because of the lack of markets for quaking aspen timber from the Rocky Mountains (see the WOOD UTILIZATION chapter). Despite this, the aspen ecosystem has been used to provide a variety of resources and opportunities (see PART 111. RESOURCES AND USES).

Natural genetic interchange and extensive colonization of aspen by seed strongly depends upon favorable climatic and microclimatic conditions and upon human intervention. At times, in regions with the right combination of environmental conditions, there is significant L, reproduction by seed; elsewhere such establishment is rare. Seed production generally is profuse; but this potential for regeneration is considerably reduced by the exacting survival requirements of aspen seedlings. Under the marginal conditions that prevail in some regions, aspen can consistently reproduce only vegetativel...

Harvesting is the removal of produce from the forest for utilization. It includes cutting, any further initial processing, such as topping and trimming, and extraction (Ford-Robertson 1971). Commercial intermediate cutting, such as commercial thinning, as well as regeneration cutting are included. Harvesting and the income that it produces sometimes is regarded as an end in itself. However, it also may be used as a means of renewing or improving a forest. Harvesting is a viable method of retaining aspen forest on many sites where it would otherwise disappear because of natural succession.

The rotation, in forestry, is the planned number of years between formation of a crop or stand and its final harvest at a specified stage of maturity (Ford-Robertson 1971). The rotation used for many species is the age of culmination of mean usable volume growth [net mean annual increment (MAI)]. At that age, usable volume divided by age reaches its highest level. That volume varies according to standards of usability. For example, if the pulpwood market accepts the entire bole plus branches, then the MA1 of aspen grown in the Lake States for pulpwood would culminate between 20 and 30...

Intermediate treatments are those applied after a new stand is successfully established and before the final harvest. These include not only intermediate cuttings - primarily thinning - but also fertilization, irrigation, and protection of the stand from damaging agents.