Treesearch

The original meaning of the word "spirit" (i.e. breath or wind) suggests an experience in which one feels touched or moved by something that can be felt but cannot be seen or grasped. The experience of spirit is often depicted through the use of symbols. Symbolism allows a concrete object, such as a tree, to represent an experience that is intangible and hard to describe. Trees have been important spiritual symbols in many human cultures. Evergreens often symbolize immortality and eternal life because they retain their leaves throughout the winter. To the Iroquois people, the white pine is...

The depth psychology ot C.G. Jung provides a set of concepts for exploring the spiritual aspect of nature. According to this view, spiritual experiences occur when basic patterns or archetypes within the psyche are projected onto natural environments. Implications of this viewpoint for natural resource management and research are discussed.

The imported willow leaf beetle, Plagiodera versicolora (Laicharting) (Coleoptera: Chrysomelidae), a multivoltine defoliator of willow and poplar (Salicaceae), is considered a significant pest throughout eastern North America (W.T. Johnson and H.H Lyon, "Insects that Feed on Trees and Shrubs," Cornell University Press, Ithaca, 1988).

Sequential observations of the ultrastructural effects of Bacillus thuringiensis var. san diego were made on midgut epithelial cells of the cottonwood leaf beetle, Chrysomela scripta F. Larvae imbibed a droplet of B. thuringiensis var. san diego containing endotoxin and live spores. Sections of midgut were prepared for transmission electron microscopy at 15-min intervals during the first hour and then hourly for a duration of 3 hr. No signs of cellular disruption were observed until 2 hr after treatment. At this time midgut epithelial cells from treated larvae appeared more elongated and...

In 1983 the fourth Wisconsin forest inventory found 14.8 million timberland acres of which 622.3 thousand acres (4%) were classified as plantations. This bulletin presents analysis and statistics of area, volume, growth, and mortality.

The fifth inventory of Minnesota's Prairie Unit reports 19.2 million acres of land, of which 660 thousand acres are forested. This bulletin presents statistical highlights and contains detailed tables of forest area, as well as timber volume, growth, removals, mortality, and ownership.

Lake States pulpwood production dropped to 8.4 million cords in 1990. Central States pulpwood production dropped by 6%--from 396 thousand cords in 1989 to 374 thousand cords in 1990. Pulpwood production is shown by county and species group for Michigan, Minnesota, Wisconsin, Iowa, Missouri, Illinois, and Indiana.

The fifth inventory of Minnesota's forests reports 51.0 million acres of land, of which 16.7 million acres are forested. This bulletin presents statistical highlights and contains detailed tables of forest area, as well as timber volume, growth, removals, mortality, and ownership.

Describes four methods of calculating competition to individual trees and compares their effectiveness in explaining the 3-year growth response of northern hardwoods after various mechanized thinning practices.

Wildlife habitat data from seven Great Lakes National Forests were combined into a wildlife-habitat matrix named NORTHWOODS. The composite NORTHWOODS data base is summarized. Multiple queries of NORTHWOODS were used to profile the wildlife community of the Upper Great Lakes region.