Harvesting practices in the southern Appalachians have moved away from clearcutting in favor of variable retention harvesting systems. A study was initiated in 1995-8 to investigate the effects of retaining varying numbers of residual trees on regeneration in seven silvicultural treatments. A second study specifically focused on stump sprouting in only three of those treatments. The treatments for first study included: a clearcut, commercial harvest, leave-tree, shelterwood, group selection, midstory treatment, and an uncut control. The second only focused on the clearcut, leave-tree, and shelterwood. These treatments were implemented in seven stands in Virginia and West Virginia over two physiographic provinces, the Appalachian plateau and Ridge and Valley. The stands were even-aged oak dominated Appalachian hardwood stands on fair quality sites with average ages ranging from 63 to 100 yrs. Permanent plots were randomly located in each stand and all overstory trees (>5m tall) were inventoried and tagged prior to harvest. Regeneration was also quantified. Harvest occurred between 1995-8. For the current studies the plots were re-inventoried 9-11 years post-harvest and all regeneration in all treatments as well as stump sprouts in the selected treatments were quantified. The first study utilized a mixed model ANOVA to analyze five species groups: oak, maple, black cherry-yellow-poplar, miscellaneous, and midstory. Response variables included importance value, average height, and density compared within species group and among treatments. Differences between sprout and seedling origin regeneration were also investigated within species group among treatment. Results indicated that oak densities were similar in all of the treatments, and stump sprouts were larger and more frequent than seedlings. Maple exhibited an increase from pre-harvest overstory importance and exhibited competitive sprouting. The black cherry-yellow-poplar group had few but highly competitive sprouts and a considerable increase in seedling origin regeneration in all treatments. The miscellaneous species densities increased as well with more competitive sprouting in some treatments. The midstory species were excluded from the analysis as it was assumed these species would not occupy canopy positions in a mature stand. The second study investigated differences in the percent of stumps that sprouted and the number of sprouts per stump. The percent data were analyzed using a non-parametric one-way ANOVA and regression analysis, while the sprouts per stump data were compared in a mixed model ANOVA and regression. Species were combined into six groups: the red oak group, chestnut oak, red maple, white oak/hickory group, mixed mesic group, and midstory group. The plateau tended to have reduced sprouting compared to the Ridge and Valley for most species groups and treatments. The red oak group, chestnut oak, and red maple exhibited reduced sprouting with increased residual basal area. The mixed mesic group did not show any effect in sprouting related to residual basal area. Only chestnut oak showed fewer sprouts per stump as residual basal area increased. / Master of Science

The effects of seven silvicultural prescriptions were examined one full growing season post-treatment on five sites in the Ridge and Valley, Cumberland Plateau, and Allegheny Plateau of Virginia and West Virginia. Prescriptions were (1) control, (2) understory control with herbicide, (3) group selection, (4) high-leave shelterwood, (5) low-leave shelterwood, (6) leave tree, and (7) clearcut. The effects of each treatment on the vascular plant community were characterized by changes in species diversity, species composition, exotic species richness, Raunkiaer's life-forms, and growth-forms. Pre-treatment, baseline data, and a randomized block design ensured the precision of post-treatment comparisons. High-disturbance treatments (i.e., low-leave shelterwood, leave tree, clearcut) exhibited lower tree-stratum species richness than unharvested treatments. Prescriptions had no effect on shrub-stratum richness. Compared to the control, woody, herb-stratum richness was higher in harvested treatments. Non-woody herb-stratum richness was unaffected. No differences in herb-stratum species diversity were detected using Shannon's (exp H') or Simpson's (1/D) indices. Non-woody species richness per 2-ha treatment plot was significantly higher than the control for high-disturbance treatments. Pre- vs. post-treatment species composition was least similar for high-disturbance treatments, as measured by qualitative and quantitative community similarity indices. Exotic woody species richness was unaffected by treatment; however, non-woody exotic species were more prevalent in high-disturbance treatments. Hemicrytophytes replaced phanerophytes as the most important life-form for harvested treatments. Therophytes were more important in harvested treatments, while the proportion of cryptophtes and chamaephytes did not change in response to treatments. Tree and shrub growth-forms were less dominant in harvested treatments, while graminoids and annual/biennial forbs were more important for high-disturbance treatments. These data represent only the initial results of a long-term study designed to examine plant-community response to silviculture for one harvest rotation length. Long-term results will aid in devising management strategies that address concerns for biodiversity without devaluing traditional resource demands. / Master of Science

The regeneration in oak-dominated stands following five silvicultural treatments was examined on four sites in the mountains of Virginia and West Virginia. Treatments included: silvicultural clearcut, leave-tree, commercial clearcut, shelterwood, and group selection. The effects of harvesting were compared among sites and among treatments. Oak regeneration dominance, measured by the relative density of dominant and codominant oak regeneration, was the most important variable calculated from the data. Oak regeneration dominance varied by site, but did not vary by silvicultural treatment; all treatments resulted in relatively low numbers. Therefore, the silvicultural treatments used here were not enough to overcome the site specific limitations to successful oak regeneration. Oak species also seemed to be less important in the regenerating stands than in their parent stands. The biggest losses in oak importance occurred on the intermediate and high quality sites; competitive oak regeneration was relatively scarce on two of the three sites with an oak site index (base age 50) of over 70 ft. Multiple linear regression analysis was used to identify the factors controlling oak regeneration at a smaller scale. The most important variables were those that described the oak stump sprouting potential, the understory and overstory oak component in the pre-harvest stand, post-harvest light and soil nitrogen levels. / Master of Science

The vegetation responses to seven silvicultural treatments one growing season after harvesting were examined on seven sites in the southern Appalachian mountains of Virginia and West Virginia. Treatments included: 1) control, 2) understory control by herbicide, 3) group selection, 4) high-leave shelterwood, 5) low-leave shelterwood, 6) leave tree, and 7) clearcut. The effects of harvesting were compared between treatments and between pre-harvest and post-harvest samplings. Species richness, percent cover, and local species extinctions were calculated for sample plots ranging in size from 1m2 to 2 ha. Vegetation richness and cover increased with increasing harvest intensity. Local species extinctions were similar in the control and disturbed treatments. Additional analyses were performed using the control, high-leave shelterwood, and clearcut on five of the seven sites to determine the relationships between soil, litter, and other environmental characteristics and vegetation in the herbaceous layer (<1 m in height). Multivariate analysis techniques were used to analyze average differences in species abundance between pre-harvest and post-harvest and to relate post-harvest vegetation to microsite characteristics. Regional-scale differences in site location were more important in explaining the presence of a species than were environmental characteristics. Within a region, species primarily were distributed along a light/litter weight gradient and secondarily along a soil properties and nutrient gradient. / Master of Science