Japanese beetles on Linden tree
I've got a Linden Tree that I planted in 2005. It's been a slow growing tree but the last few summers it's really started to get big and provide some much needed shade. Last year I started to see many of the leaves were eaten through. This summer its worse and almost all leaves have been eaten through. I've found the Japanese beetle (many of them actually) on this tree both this summer and last. I have purchased the Japanese beetle traps that are sold at big box home improvement stores. Although these traps have caught some Japanese beetles, they have not caught them all and the damage has continued. I'm at a loss in how to further try to deal with this problem. Is there a non toxic spray I can spray on the leaves to keep these beetles away? Please advise on how I can eradicate these horrible Japanese beetles.
Washington County Minnesota