Abstract
Emerald ash borer is an invasive wood-boring beetle that threatens North American ash species. This research describes sugar resources that may limit establishment of Tetrastichus planipennisi, a biocontrol agent. Allometric equations were developed for several native and non-native shrub species. Stem diameter significantly predicted shrub flowers, biomass, and age for all species. To examine possible sugar resources used by T. planipennisi, correlations were applied. Of species positively correlated with T. planipennisi recovery, some have the potential of providing floral nectar (border privet (Ligustrum obtusifolium) Siebold & Zucc., Virginia creeper (Parthenocissus quinquefolia) (L.) Planch., and black locust (Robinia pseudoacacia) L.) and/or extrafloral nectar (border privet, black cherry (Prunus serotina) Ehrh., and black locust) to the parasitoids. All sites that had high recoveries of T. planipennisi were young, poorly-stocked forests with small-diameter ash trees. Tetrastichus planipennisi may utilize sugar from one of these sources or these characteristics may indicate suitable microhabitats.