Treesearch

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.

There are basically two approaches to regenerating aspen stands-sexual reproduction using seed, or vegetative regeneration by root suckering. In the West, root suckering is the most practical method. The advantage of having an existing, well established root system capable of producing numerous root suckers easily outweighs natural or artificial reforestation in the West. Root suckers do not require good seed years or stringent microclimatic conditions (see the VEGETATIVE REGENERATION chapter), and can be produced in much greater abundance and more economically than nursery grown seedlings...

The aspen ecosystem may be managed for any one or more of the assets discussed in PART 111. RESOURCES AND USES. It is truly a multiple use type, especially in the West, where it has had limited marketability for its fiber (see the WOOD UTILIZATION chapter). Many forest types are managed for their economic value as timber. This value is the source of money for management activities, such as access road construction and maintenance, harvesting costs, regeneration costs, intermediate stand treatments, and other silvicultural treatments.

Aspen is valued for its scenic beauty. One indication of this is the trips to the "high country" that many forest visitors make to view the autumn color changes (fig. 1). Another is the frequency with which aspen is planted in urban and suburban areas. Subjective generalizations about the esthetic uses of aspen, although reasonable, provide only rough guidance for management of scenic quality. They can not be used to compare the relative beauty of different scenes, or to determine how much scenic beauty changes as the physical characteristics of the scene change, either naturally or as the...

In forestry, a nurse crop generally is a crop of trees or shrubs that fosters the development of another tree species, usually by protecting the second species, during its youth, from frost, insolation, or wind (Ford-Robertson 1971). Aspen may be a nurse crop for shade-tolerant tree species that do not become established in full sunlight (e.g., Engelmann spruce). Through the natural successional process, aspen often serves in this capacity. In the West, aspen also can be considered a nurse crop to the forage-rich mix of shade-tolerant understory species (see the VEGETATION ASSOCIATIONS and...

This chapter considers aspen growth as a process, and discusses some characteristics of the growth and development of trees and stands. For the most part, factors affecting growth are discussed elsewhere, particularly in the GENETICS AND VARIATION chapter and in chapters in PART 11. ECOLOGY. Aspen growth as it relates to wood production is examined in the WOOD RESOURCE chapter.

Effective inventory, management, and planning for recreation resources depend upon knowing why persons choose certain environments to attain specific goals, and what elements in those environments facilitate goal-attainment. Research focused on relating motives for participation to specific components in the environment has had only limited success. This paper proposes an alternative organization of the motive-behavior/environment relationship intended to improve the predictive power of this line of research. The model is founded on an attempt to separate the process of recreation behavior...

The term "morphology" is used broadly here to include the exterior form of the tree above ground, the root system, and the stand.