Canadian Forest Service Publications
Establishment and spread of two introduced parasitoids (Ichneumonidae) of the birch leafminer, Fenusa pusilla (Tenthredinidae). 2000. Langor, D.W.; Digweed, S.C.; Williams, D.J.M.; Spence, J.R.; Saunders, C. BioControl 45: 415-423.
Issued by: Northern Forestry Centre
Catalog ID: 18187
Lathrolestes nigricollis and Grypocentrus albipes, Palaearctic specialist parasitoids of the birch-leafmining sawfly Fenusa pusilla, were imported from central Europe and released during 1994-96 at three locations in Edmonton, Alberta, Canada (Sunstar Nursery (SN), University of Alberta (UA) and Howard Road). Parasitoids became established at two locations (SN and UA), L. nigricollis at both locations, and G. albipes at one location (UA), and were recovered for 3-5 years after their release. L. nigricollis dispersed throughout most of Edmonton, at least 13 km from release sites, but G. albipes were recovered only 400-500 m from one release site. Five years after introduction at SN, percent parasitism by L. nigricollis was 78% and 84% for the first and second generations, respectively, and about 48% of parasitoid eggs were encapsulated.