Properly Control Japanese Beetles
The damage caused by japanese beetles to trees is pretty simple to identify. You’ll either be able to see the beetle in the act, or just find leaves that are skeletonized. There are a few different ways to combat the threat of japanese beetles.
Defense: You can either spray the affected part of your tree with a japanese beetle killer or a product known as “Neem Oil” Neem oil works as kind of an anti-feeding agent.
Remove Manually: Since Japanese Beetles are slow, believe it or not you can actually pick them off of leaves yourself.
Prevention: You can use the following chemicals on the grubs that turn into japanese beetles. They are known as Grub Guard and Milky Spore.
Trap Them: You can purchase a trap if you’ve got a large yard and every few weeks catch them.