Comment from Mark Mayer

The introduction of this species into Eastern North America for hemlock woolly adelgid control is a good idea. In New Jersey we have released Sasajiscymnus tsugae (ST) from Japan and Scymnus sinuanodulus (SS) from China as summer predators of the hemlock woolly adelgid and we have only recovered ST in very low numbers. SS has never been recovered other than in the same year that it was released. ST has not been recovered in sufficient numbers to indicate that it has the potential to be a successful partner with the winter predator, Laricobius nigrinus. L. nigrinus is doing well in New Jersey as we are recovering increasing numbers in successive springs. As LN and SC have coevolved in the Pacific Northwest while feeding on the same host but not occupying the same niche there should be no disadvantages to them coexisting in the eastern hemlock forest. They are controlling hemlock woolly adelgid in the Pacific Northwest and the probability is good that they should be able to control the hemlock woolly adelgid in the east. As more hemlocks die with each successive year there is little time to waste in getting another predator into the field. The more tools, the better and the addition of SC would expand the toolkit and may give us a more efficient summer predator than the two exotic ladybeetle species.