The seasonal phenology of Halyomorpha halys (Stål) were documented at Rodale Organic Tree Farm in Allentown, PA from 2005-2007. In 2007 females were collected weekly at the same site to evaluate the relationship between host plant phenology and reproductive physiology. Field collected females from Rodale were dissected and assigned to an ovarian ranking developed in the laboratory using known-aged females. Mated status, weight and flight activity were also evaluated. Flight activity of H. halys was monitored using a black light trap. This data will be used to reveal annual patterns in host association, flight activity and to verify the number of generations per year.