Japanese Beetles
The Japanese Beetle (Popillia japonica) is not a problem in Japan where natural predators control it but here in the US we’re not so lucky.
Single beetles do a bit of damage to leaves and flowers.
Large numbers, however, can eat so much of a plant that they become threatening to the existence of the plant. We’ve seen entire mature trees nearly completly defoliated by them.
While many methods are available to help control them, incuding poisons, pheremone traps and even hand removal (dumping them into a bowl of soapy water to eliminate them), the ones you miss will happily make more.
Over the years we’ve witnessed some preadtors start to go after them and floating row covers can protect plants or garden crops until they are large enough to withstand some beetle damage. Some sources say they are especially attracted to soy plants and one year a nearby farmer planted hundreds of acres of soy. The following year we were especially inundated with them. Coincidence?
What's In My Yard 