I made a huge mistake the other day. I was chit-chatting with a woman at work about our gardens. She was complaining about the number of Japanese Beetles that had invaded her gardens. "Knock on wood," I said, "I've not seen one yet this year.." Big mistake. I think our conversation was being recorded by the BIA (Beetle Intelligence Agency) because they have invaded, big time!
These annoying little bugs can leave your plants looking like your grandmothers favorite doily. While one small beetle doesn't do much damage on it's own, the mass numbers can destroy a plant in no time. There are literally hundreds of plants that they enjoy; but tend to favor roses most of all. They are attracted to the scent and the heat of the plant since most roses are in full sun.
As the Japanese Beetle feeds, it emits a pheromone that attracts others to enjoy the feast.
There are no easy methods to ending the Beetle madness. I do not use chemicals in my gardens, outside of some insecticidal soap. A good spray of the soap kills the visible beetles but has no residual effect.
I recall reading one of Martha's "Remembering" column years ago when she wrote about one of her childhood duties; to pick off the beetles and kill them. I don't have that kind of time, but I have shaken a few blooms over a bucket of soapy water and collected quite a few dead beetles. Perhaps I need to rent a child for a few more weeks to help keep the beetles at bay. (just kidding)
They'll all be gone by the beginning of August, having bred like rabbits (they are NOT modest when it comes to sex... they really should get a room) and eaten themselves into a stupor. It's a never ending circle of life. I for one have learned my lesson. I'll never brag about being 'beetle-less' again.