Advances in computer technology have made it possible for designers to manipulate realistic images on a computer screen. Previously, most computer generated images consisted of line drawings or distorted grid perspectives. A program known as PC/NewPerspectives, which generated distorted grid perspectives, has been in use by US Forest Service Landscape Architects who use it to determine the visual impact of a proposed harvest unit and manipulate the layout to reduce the impact. New programs in video imagery offer the opportunity to design harvest layouts on a more realistic format, which may also be used as a communication tool to relay to members of the public what the proposed alteration would look like. This study compares the two media in terms of landscape preference and acceptability of activity to determine the difference in the two media as communication tools and how this would influence their effectiveness. / M.L.A.

Group selection has recently emerged as an alternative silvicultural system to clearcutting in Appalachian hardwood forests, but there is little, if any, information on the effects of group selection on wildlife. Thus, I studied and compared the effects of group selection and clearcut openings on wildlife in the Jefferson National Forest, Virginia. Breeding birds were censused 1 year before and 2 years after harvesting at 20 group selection openings, 4 clearcut openings, 18 sites in the mature even-aged forest adjacent to the openings, and 29 control sites. I also compared use of group selection openings and clearcut openings by white-tailed deer. The number of species and the total number of birds decreased at the openings and in the forest adjacent to the openings after harvesting with both methods. (Seven species increased and 9 species decreased in the openings after harvesting. Four species decreased in the forest adjacent to the openings after harvesting. Indigo buntings and rufous-sided towhees increased more at the interior of clearcut openings than at the edge of clearcut openings or in group selection openings. Sites within the clearcut openings where groups of trees were left uncut were not used more by birds than clearcut sites without trees. (The number and proportion of stumps with sprouts browsed by white-tailed deer was greater in group selection openings than in clearcut openings. Clearcut and large group selection openings provided breeding habitat for the same bird species. The smaller group selection openings were not used by some species found in the clearcut openings. However, creating a variety of opening sizes probably will provide the maximum benefit for all wildlife species that use early successional habitat. The same species were negatively affected, and to a similar degree, by group selection and clearcut openings. Both types of openings had negative impacts on forest-interior bird species in the adjacent forest. However, if the same acreage is harvested, group selection will affect a greater area of adjacent forest than clearcutting, because smaller openings have greater edge to area ratios. / Ph. D.