Thesis (M.S.)--University of Massachusetts Amherst, 2008. / Includes bibliographical references (p. 35-39).

Invasive species have become an increasing threat to many habitats worldwide. This research addressed the questions of whether several invasive woody plants can germinate, survive and grow in light levels typical of an undisturbed forest understory, and also whether alteration of the nitrogen cycle by one invader is likely to increase the rate of invasion by others.

The spatial distributions of four plant species native to Asia, yet considered invasive in southwestern Virginia, were studied in order to produce predictive habitat maps. The study took place in the mountains to the north of Blacksburg, VA, on National Forest lands. A random GPS survey of each of the four species, Microstegium vimineum, Lonicera japonica, Rosa multiflora and Elaeagnus umbellate, was used in combination with a series of Geographic Information System (GIS) layers representing environmental variables (Elevation, Aspect, Roads, Trails, Streams, & Normalized Difference Moisture Index) to produce logistic regression models. After field- validating the models, the models were ranked according to usefulness, with the E. umbellate model proving most accurate. It is hoped that such GIS models will allow forest managers to more productively search for invasive species within their jurisdiction, by indicating sites more likely to provide habitat suitable to the invasive species described by the model. A non-GIS search for correlations between the study species' presence and field-collected discrete environmental variables was also included. Both Disturbance and Canopy Cover were considered for their effect upon Microstegium vimineum, Lonicera japonica, Rosa multiflora and Elaeagnus umbellate presence. Using Pearson's Correlation with the Canopy Cover data, and Chi-squared Correlation with the Disturbance data, only R. multiflora and E. umbellate showed significant correlation to decreasing canopy cover. / Master of Science

No description available.

The tocopherol (Vitamin E) content of forage from three invasive shrub species was measured to assess the value of the shrubs as a source of vitamin E for goats browsing on overgrown Appalachian pastures. Plant leaf clusters were collected from multiflora rose (Rosa multiflora Thunb.), autumn olive (Elaeagnus umbellata Thunb.), and Morrow's honeysuckle (Lonicera morowii Gray) in replicated plots at a site in southern West Virginia during the 1999 growing season. Alpha-, beta-, gamma-, and delta-tocopherol were extracted with hexane, separated by high performance liquid chromatography on a normal-phase diol column, and quantified. Significant differences (P<0.001) in concentration were found among species for all forms of tocopherol. Alpha-tocopherol predominated, accounting for more than 90% of the total tocopherols in all three species. Alpha-tocopherol levels increased in all species with maturity; however, the magnitude of the increase was not the same in all species. At the end of the growing season, autumn olive had the highest levels of alpha-tocopherol (1270 ± 55 ppm dry matter [DM]), followed by Morrow's honeysuckle (840 ± 55 ppm DM), and multiflora rose (610 ± 55 ppm DM). Goats grazing on mature browse may obtain adequate intake of vitamin E. High nutritive value and/or low concentrations of antiquality factors may not coincide with the high levels of vitamin E found in mature tissue, and the actual vitamin E intake will depend on the feeding behavior of the goat. / Master of Science