Hi, I'm hoping this board is active enough to help me with a large problem....ROSE CHAFERS! my mom has an infestation of these buggers in her yard. first I spotted them eating the leaves of a small oak tree, then I saw hundreds on a rose bush eating the leaves and flowers, there were a bunch eating leaves of a white birch tree and I saw more on other plants in her yard. I've looked up ways to remove them but the things I find are just if there is a small number of the bugs (we can;t pick off every single one). The other option is using a pesticide, which I'm against. My mom thought she could spray the trees with soapy water but I'm afraid that might harm the tree. Does anyone have experience killing these bugs?
Oh, and my mom lives in central Ontario , Canada. TIA