Japanese beetle

For the last 5 years we have been inundated by Japanese beetles. They eat my Newport plum and Alpine currant to lace, snack on my River Birch and generally saturate by yard. Most years we have so many you can actually hear them moving around. I have used Grubex on the grass annually, sprayed various poisons and made vats of what my kids call beetle stew (picking them off by hand and drowning them in water). This year we do have less (we've had way cooler weather than usual) but they are still here.