Our orchard has been invaded by little brownish, green beetles. They swarmed onto the grapes and the fruit trees (except the mulberry), so my husband brought a bunch home in an empty water bottle for me. I’d never seen them before. Have you? Here’s a picture of one of the beetles on my arm.

So what do you think? Good bug or bad bug?

My husband was the one who finally discovered what it is by googling multiple search terms including “beige beetle” “orange legs” “fruit trees” and a few others. This little guy is known as the Rose Chafer Beetle, or Macrodactylus subspinosus. According to Wikipedia:

After adult rose chafers emerge in late May to mid-June, they aggregate on leaves, buds, flowers, and fruit, in order to feed and mate. By chewing on plant tissues, the rose chafer induces the release of volatile compounds from the plant. Using their antennae, rose chafers can detect the plant compounds in the air and orient themselves in the direction of the feeding conspecific, leading to an aggregation of the beetles. 

The adult beetle feeds on the foliage, flowers, and fruit of many plants including grapes, apples, peaches, roses, and other garden flowers and fruits. On roses it skeletonizes the leaves, which can be rather bothersome for avid gardeners. Rose chafers are also a problem for vineyards as they eat the grapes at bloom as well as skeletonize the leaves. They also tend to appear suddenly and in swarms, and vines with over 100 rose chafers per plant have been observed. This huge amount of damage can result in almost total loss of photosynthetically active leaf area as well as reducing or prohibiting pollination. The larvae also cause damage as they feed on the roots of the plants, which can limit growth.

So I’m guessing it’s a good thing we caught this early. As soon as he told me how many beetles were on the trees (a lot!) I ran out and got some neem oil to dilute and spray the trees with. Hopefully this will control the spread before they do much more damage. I only noticed a few leaves with severe damage, more so on the grapes than the fruit trees, though they were in larger numbers on the fruit trees. Maybe they like to eat the grape leaves and get down n dirty on the apple leaves? Who knows. Strange bugs.

I was letting the beetle crawl all over me so we could get a picture of it. I’m very thankful now that it wasn’t a blister beetle, which looks similar. Why? Do a quick google of “blister beetle dermatitis” and you’ll see. I might have to be more careful about what I let crawl on me in the future. Eep!

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