Field releases of the exotic parasitoid Trissolcus japonicus (Hymenoptera: Scelionidae) and survey of native parasitoids attacking Halyomorpha halys (Hemiptera: Pentatomidae) in Michigan.

An adventive population of the exotic parasitoid wasp, Trissolcus japonicus (Ashmead) (Hymenoptera: Scelionidae), discovered in Michigan in 2018, is a promising biological control agent of the invasive Halyomorpha halys (Stål) (Hemiptera: Pentatomidae). Following its discovery, field releases of Tr. japonicus were conducted over 2 yr in southern Michigan, to test how release size or release frequency impacts establishment.