Croft, Genevieve (Georgetown University). Mentor: Eric Nagy (University of Virginia). Effects of local light environment on insect herbivore damage and seedling growth for three tree species.

Abstract: This study addresses the interaction between local plant light environment and the amount of herbivory on seedlings of three tree species intermediate in their shade tolerance, Acer rubrum, Quercus alba and Quercus rubra, which commonly inhabit a variety of light environments at the Mountain Lake Biological Preserve, Giles County, Virginia, USA. Three light environment treatments - Gap, Non-Gap, and a within-gap artificial Shade treatment - completed a split-plot design used to assess differences in herbivory for two distinct light environments. Herbivory was measured both early and three weeks later, for a measure of the Early, Late, and Change in herbivory. A significant effect of light environment treatment was found for Early, but not Late, herbivory data. Separated by species, a significant effect of treatment was found only for Q. alba for both Early and Late Herbivory, indicating greater herbivory in the Non-Gap subplot on both occasions. These results may indicate a plant species-specific response to differences in light levels resulting in differences in herbivore activity. They may also reflect species-specific differences in herbivore type, and these herbivores' micro-environmental preferences.