Look for these shiny green and copper beetles feeding on grape leaves, roses and many other trees and shrubs. Where possible, homeowners can knock adults into a bucket of soapy water (to smother them). Several insecticides are registered for the adults in the nursery, including BeetleGONE and Imidan.
European chafer (Amphimallon majale) adults are also starting to emerge. Look for medium brown scarab beetle swarming blooming Linden trees (e.g. Tilia cordata). Historically we see them around Canada day in the Guelph area.
And don’t forget about our little friends, the Rose Chafers (Macrodactylus subspinosus). They are also out in full force. These scarab beetles feed on the flowers, fruit and foliage of several ornamentals. The larval stage feeds on roots of grasses and weeds (usually a sod nursery pest). Like most scarab beetles, females are more likely to lay their eggs in sandy soils and will avoid egg laying in clay soils. Insecticides for the grub stage of other scarab beetles will also reduce larvae of rose chafer.
Preventative applications of Intercept and Acelepryn are registered for white grubs in nursery and greenhouse production and the application period begins now. (Above photo: European chafer larval feeding damage)