Epargyreus clarus, silver spotted skipper, is a common Lepidopteran pest of forage and grain soybean [Glycine max, (L) Merr.] in several counties in the Delmarva region. The conducive climate of this region has been proven to elevate the pest growth and cause significant annual economic lose to the sustainable crop. Soybean field observations of the regional farms and the research plots at the University of Maryland Eastern Shore, Princess Anne, Maryland showed, as in previous years (2003 – 2006), from 50% to 70% leaf defoliation of grain and forage soybeans, respectively. In vitro studies of field grown forage soybeans (Moon Cake- control, 7P116, XB-32, Donegal, Tyrone, Tara, and Derry) and grain soybean (Schillenger 495RC- control, 9444169, SE73753, and SE73090) leaves were used to conduct an assay on the defoliation and tolerance of the Lepidopteran pest [0.1 -0.66g. weight (wt.) of larvae from control plots]. The forage soybeans assay showed that 7P116 was defoliated 85% with larvae wt. gain of 0.646g compared to control (Moon Cake) of 25% and 0.058g. wt., respectively. The grain soybeans assay showed that 491734 was 50% defoliated with larvae wt. gain of 0.732g compared to control (Schillenger 495RC) of 20% with 0.148g, respectively. These genotypes were found to be most significantly susceptible to E. clarus infection than the other assayed soybeans. Therefore, the data from this experiment suggest that genotype, larvae weight, and other environment conditions warrant further study on a routine basis as a viable strategy for insect control.