Images: Rugosa rose before pestilence and Rugosa with Japanese Beetles.
"Pestilence of the Moment" is how I describe having one annoying or damaging insect appear about the time another has finished its cycle of destruction.
Because I seldom use pesticides, insects must confer and have declared my yard a no-kill zone. I can visualize these little critters packing their bags and catching the first air tram to my yard.
I try not to use pesticides on plants because most kill the good insects (including frogs, toads, and some birds) with the bad. Good insects, birds and bats can perform wonders on the insect pests if you have the right match: Predator and their favorite B&B.
I have a good supply of Praying Mantis, wasps, damselflies, dragonflies, Pennsylvania Leather-wings, and others going about their business mostly unobserved.
Bats, swallows, robins, Indigo Blue Buntings, chickadees are just a few that help. The Common Crow consumes enormous amounts of grasshoppers, cutworms and other harmful insects.
Sometimes it's a tossup on the benefits. We have moles eating larva in the yard. This is especially beneficial because they eat the larva of Japanese Beetles. The downside is they make tunnels and the dogs insist on digging them up.
I've had a huge number of Japanese Beetles. They are especially fond of my Rugosa roses although they started at the top of my cherry tree.
I have found no good chemical Japanese Beetle killer that doesn't kill bees and other beneficial insects. From everything I've read, do not use the commercial traps; the smell entices more beetles to your yard.
Although I haven't used, some Master Gardeners say they've had control benefits using milky spore powder (Bacillus papillae). You may want to try nematodes or Neem oil organic insecticide.
If we go on a week's vacation, the Japanese Beetles confer. They decide my harden is on the vegan five star restaurant tour and they pack the place.
Here's my attempt for cutting down the population of Japanese Beetles:
Early morning and dusk, I take a zip lock bag to the garden. Hold it under the beetles and shake them into the bag. If done early or late, they are sluggish and don't fly away as easily. Also, if you put a couple of rose petals in the bag, they just think they are in another diner. Zip closed and tomorrow they are dead.
Japanese Beetles tart at the highest point on their food of preference.
They have over 200 plants they consider eating but seem to prefer roses.
They smell each other from miles away so the more beetles you have, the more you will attract.
Picking them off plants never totally eliminates them but they tend to be fewer in number if you do this daily and cut down on insect body odor. A plant seldom dies from Japanese Beetles but it can do a lot of damage and make it very unsightly. Plus, when they pack a flower head (as above), bees can't get to the pollen.
While my gardens have just started the Japanese Beetle invasion, on the plus side we have also just started the firefly (lightening bug) season. One recent warm evening, when there was little moonlight, the entire woods looked as if it had been draped in twinkle lights. Stunning!
As Lou Erickson said, "Gardening requires lots of water - most of it in the form of perspiration."