they make japanese beetle traps that dont have pesticide. Go to home depot, lowes or ur local gardening center and ask for em. They work great and you wont have another problem. The bait is a scent that smells like a giant orgy, so they all go to it but get trapped in a bag and cant fly out, heres a picture of it.
I like to pick my squash when it's only about an inch in diameter. I slice it a half inch thick and cook it sprayed with butter on my double sided George Forman grill. About 5 minutes and it's done al dente and cooks just a bit more on the plate. Awesome good!
Another spray of butter and a sprinkle of Season-All seasoned salt and you've got a **** of a good side dish.