Treesearch

A report on the symposium-fair held 19-23 May, 1975 at the C. H. Marvin Center, the George Washington University, Washington, D.C., containing 33 papers. Sections are devoted to defining the role of natural environments and human development, research on urban children and the natural environment, and community and institutional response to fostering desirable relationships between nature and development of urban children.

An attempt to identify stages or episodes in the first 20 years of life. Stages are briefly explained and discussed, arranged in age class sequence, and, where possible, are associated with environments related to urban life.

Hemlock-beech forests once covered 6 million acres of the Allegheny Plateau in Pennsylvania and New York. To preserve a remnant of this forest, the Federal Government purchased the last remaining uncut hemlock-beech forest in 1936. Four years later, half of this area was set aside in the Tionesta Scenic Area, primarily for public enjoyment; the other half was set aside in the Tionesta Research Natural Area for scientific study. Both areas are administered by the Forest Service, U.S. Department of Agriculture. A brief ecological history of the area shows the changes that have occurred in...

Silvicultural cleaning production varied from .15 to .34 acres per man day using light weight chain saws in young Spruce and Fir stands in Central Nova Scotia. Direct labor and saw costs, in cleaning young softwood stands in Nova Scotia, can be expected to range generally from $55.00 to $90.00 per acre, depending on crew experience, stand density, and equipment used.

Data collected since the 1950s from commercial treatments on more than 400 acres in the Penobscot Experimental Forest in Maine indicate a high mortality rate of 520 percent of net growth in the woodland preserve where timber is not harvested, a low mortality rate of 16 percent of net growth under the selection system. As the intensity of silvicultural treatment increased, periodic net annual growth increased from 10 cubic feet per acre (0.7 m³/ha) in the woodland preserve to 56 cubic feet per acre (3.9 m³/ha) under the selection system.

Forest fertilization is a useful tool that, when combined with other silvicultural practices, results in increased forest growth. Many experiments have demonstrated that both hardwoods and conifers of the northern forest respond to the addition of one or more nutrients. Examples of pitfalls and successes are given. Present status of research and future research needs are discussed.

Summarizes the extensive literature for northern forest species covering site index curves, site index species comparisons, growth intercepts, soil-site studies, plant indicators, physiographic site classifications, and soil survey studies. The advantages and disadvantages of each are discussed, and suggestions are made for future research using each of these methods. Suggests a complementary framework that coordinates site quality, yield, and forest land classification. Discusses how this complementary framework can help in practicing more intensive timber management.

Existing regional growth-and-yield information for most of the northern forest types is summarized by species. Present research is concentrated on growth-simulation models, constructed by either aggregating available information or through individual tree growth studies. A uniformity of more refined measurements is needed so that future growth models can be tried for other species and forest types.