Treesearch

Continuous time and motion study techniques were used to develop productivity and cost estimators for the skidding component of ground-based logging systems, operating on steep terrain using preplanned skid roads. Comparisons of productivity and costs were analyzed for an overland random access skidding method, verses a skidding method utilizing a network of preplanned designated bladed skid roads. Productivity levels decreased while costs increased as the amount of winch line cable needed to be pulled to choke logs increased. Although estimated skidding costs were higher when the designate...

The West Virginia University (WVU) Forest is a 7,600-acre tract located along the leading edge of gypsy moth infestation. The hazard rating study at the WVU Forest serves three objectives. First, hazard rating is being used to determine the extent and distribution of damage that can be expected when gypsy moth defoliation occurs. Second, susceptibility and vulnerability equations currently available in the literature are being tested. Finally, through the use of computer technologies such as geographic information systems (GIS), the project demonstrates how to streamline the hazard rating...

Non-destructive measurements of light penetration were made at 10 heights in the canopy on twelve different sites in the PA oak forest where the Blackmo 88 spray-micrometeorological experiment was conducted. Vertical profiles of Leaf Area Index, LAI, were calculated from these measurements, and the data were used to define the spatial variability of the forest canopy density.

The response of a nongame bird community to tree defoliation and mortality caused by gypsy moths was studied during the summers of 1984, 1985, 1987, and 1988 in deciduous forest habitat of eastern West Virginia. Birds and structural vegetation characteristics were sampled on 42 permanent stations. The 1984 and 1985 stations were considered undefoliated because whole tree defoliation did not occur until 1986. The 1987 and 1988 stations were categorized as defoliated or undefoliated based on canopy coverage and snag density values when compared to the pooled 1984 and 1985 station values....

It is generally accepted that when gypsy moths rest in the litter survival is low due to predation by ground-foraging generalist predators and that predation can maintain these populations indefinitely. Forest Service research on predators of gypsy moth continues to focus on population dynamics, the mechanisms of predation and forest management implications.

The overall objective of this project was to determine the effects of defoliation on gray squirrel habitat. We will evaluate the existing Habitat Suitability Index (HSI) Model for gray squirrels on the University Forest and determine the effects of thinning on HSI values computed for thinned and unthinned stands. Habitat variables used in the U. S. Fish and Wildlife Service gray squirrel model were measured on 8 10-12 ha treatment (to be thinned in spring 1990) and 8 unthinned stands on the University Forest, Morgantown, WV, and 3 other nearby hardwood tracts. Six different habitat...

The impact of forest thinning, as an alternative gypsy moth management technique, on insectivorous birds and small mammals is being investigated in the West Virginia University Forest. The effects of thinning on predation of gypsy moth larvae and pupae by vertebrates are also being examined. Pre-thinning studies were conducted during the spring, summer, and fall of 1989 in 8 control stands and in 8 stands scheduled to be thinned during the winter of 1989-1990. Insectivorous birds were spot-mapped, and small mammals were pitfall and snap trapped to estimate abundance per stand. Mast traps...

Viral immediate early gene products are usually regulatory proteins that control expression of other viral genes at the transcriptional level or are proteins that are part of the viral DNA replication complex. The identification and functional characterization of the immediate early gene products of Lymantria dispar nuclear polyhedrosis virus (LdNPV) will further our understanding of viral pathogenesis at the molecular level and may yield insights into a molecular means of enhancing viral potency. In addition, the transcriptional promoters of these genes can be used to drive the expression...

Several studies are underway to test and evaluate the use of silvicultural treatments to minimize gypsy moth impacts. Treatment objectives are to change stand susceptibility to gypsy moth defoliation or stand vulnerability to damage after defoliation. Decision charts have been developed to help forest and land managers to select the appropriate treatment for their forest and insect conditions. Extensive plots to test silvicultural manipulations have been and are being established by several state organizations including the West Virginia Division of Forestry, Ohio Division of Forestry,...

A gypsy moth hazard exists when forest conditions prevail that are conducive to extensive damage from gypsy moth. Combining forest hazard rating with information on insect population trends provides the basis for predicting the probability (risk) of an event occurring. The likelihood of defoliation is termed susceptibility and the probability of damage (mortality, growth loss, reduced aesthetics, etc.) is called vulnerability. Hazard rating systems are usually developed by making empirical observations of forest stands that are exposed to a gypsy moth outbreak and formulating a prediction...