Treesearch

Seedlings from 40 seed sources of ponderosa pine (Pinus ponderosa Laws.) were planted on a strip-mine spoil in central Pennsylvania in 1969. Survival of seedlings from different sources ranged from 23 to 90 percent after six growing seasons. The average height of the seedlings ranged from 67 to 140 cm for the same period. Eight sources produced seedlings that were average or above in both height growth and survival.

Employment in the logging industry dropped 28 percent between 1950 and 1970, while output of industrial roundwood increased 31 percent. Today's loggers are older, better educated, and more skilled. A large proportion are self-employed, many work less than a full year, and a substantial number have incomes below the poverty level. Mechanization of timber harvesting will continue to affect the size and makeup of the labor force.

Songbird populations can be related to habitat components by a method that allows the simultaneous determination of habitat requirements for a variety of species . Through correlation and multiple-regression analyses, 10 bird species were studied in a suburban habitat, which was stratified according to human density. Variables used to account for bird distribution included aspects of vegetation, human activity, and structures.

The economic impacts of a gypsy moth infestation on homeowners and on managers of recreation areas (commercial, public, and quasi-public) were determined from data collected via interviews with 540 homeowners and 170 managers of recreation areas in New York and Pennsylvania. The approach to measuring the impact of gypsy moth was to determine the interaction of a specific effect of an infestation (tree defoliation, tree mortality, nuisance) with a specific ownership objective (the reason a person has for owning or managing a property). Data were also collected on costs of controlling the...

Discusses 1975 pulpwood production and receipts and recent production trends in the Lake States and Central States. Gives pulpwood production in the Lake States by species for each county and compares production by Forest Survey Unit with that of previous years. Presents 1975 pulpwood and receipts data by state for the Central States, and shows four production classes by county.

Prescribed fires in mature red pine stands reduced shrub competition and the organic layer thickness. The fires reduced nutrient in the forest floor, increased them in the mineral soil, but had no effect on overstory growth.

Simulating natural damage to leaders of forest-grown seedlings of yellow birch and sugar maple resulted in no loss of vigor but a loss in net height growth. Leader elongation depended upon seedling, shoot, and bud characteristics rather than on the extent of damage.

Ground water recharge under hardwood and pine forests was measured from 1962 to 1971 on the Udell Experimental Forest in Michigan. Hardwood forests produced more net ground water than pine forests by an average of 50 and 100 mm/year, using two methods of analysis. Shallow water-table lands yield 80 to 100 mm/year less water than deep, well-drained sands. Water yield decreased the most between drainage classification of pine plantation.

Reports results of fertilizing and thinning pole-size sugar maple and yellow birch crop trees on six different sites. Thinning significantly increased diameter growth, but fertilization did not. Crop trees on moist (moderately well-drained) soils have tended to respond to fertilization. Discusses silvicultural implications.

A set of value concepts and methods for appraising both values-at-risk and change in value resulting from wildfire are presented. Emphasis is placed on the effects of forest fires in terms of their affects on human and organization goal achievement. Fire effects that help achieve goals are beneficial; those that hinder goal achievement are undesirable and create damage.