This Lodi apple tree was my earliest ripening variety. Once Japanese beetles discovered it, they released pheromones that drew in more of their kind and aggregated, as in the photo. The problem was made worse by a neighbor placing two Japanese beetle traps within 75 feet of my small orchard. These traps attract more than they kill, according to entomologists. Disease and wind storms took this and three other trees out many years ago. Japanese Beetles persist as an annual scourge.

I found less is more in dealing with the beetles. Part of a gardener’s life is watching what is happening among garden plants, insect activity particularly. It took only a day or two to see the pest had arrived in the plots. These solitary insects favored the invasive weed velvetleaf, skeletonizing the upper leaves until I knocked them off into a bucket of soapy water. Within a few days of initial observation, they moved on.

I expected them to hit the green bean plants next, yet they found better food in the form of new growth on the Zestar! apple tree laden with fruit. I looked up and saw they made lacy patterns in the high leaves, the ones most tender and delicious to the pests. No longer were they solitary. Their feeding released aggregation pheromones that attracted additional beetles. When I saw them there was vigorous eating and mating taking place. It was like they were having a party.

Lesson one: don’t assume the first plant the beetles land on is where they’ll stay. On my property they moved from velvetleaf to the top of a heavily fruiting apple tree, where they congregated, fed, and mated.

Lesson two: Japanese Beetles have favored plants and seek them out. From years of observation, once my neighbor stopped putting out traps, I found they stayed only a short period in my garden then left for other, nearby food. There is ample food they favor in the state park about 100 yards from my door.

One summer I inspected a nearby soybean field and found Japanese beetles throughout it in disturbing numbers. I have long suspected those fields became their next destination. On Monday I drove around the area and found the nearest farm fields were planted in corn, and others were rotated to hay and forage grasses. Absent soybeans, the beetles may have come to roost for the season in my apple tree and the nearby state park.

It is curious they landed on one variety of apple tree and left the other four alone, even though one is within 25 feet of the Zestar! This suggests they can distinguish among apple varieties. They appear to have a highly refined capability to differentiate between nutritional values of a variety of garden plants. They were so high in the tree, I couldn’t reach them to pick them off the leaves. In any case, by the next morning they had fed on the new leaf growth of the tree and moved on. I could find them nowhere in our yard.

Over years I learned to live with Japanese Beetles and control the damage they cause as I can. This is dependent on understanding their behavior. Their brief lives have a predictable arc and we must do what we can to influence it in a way that protects garden vegetables.

In doing so with these and other pests, we gardeners make the best effort we can to produce a crop.