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Japanese Beetles: The Perfect Bug

datura This summer we have had a sizable invasion of Japanese Beetles in our garden. We’ve had them before, and, I thought at the time, a lot of them. It turns out that the number of Japanese Beetles of the past were small compared to this year’s visitors to our garden. I’m not exactly sure why but I figure it’s the cyclical nature of the garden. It’s a bad year for Japanese Beetles, from our point of view, and they are a well-designed pest.

Japanese Beetles are a perfect bug, from an insect point of view. They don’t have many natural predators in the US. They feed on the leaves of many many common plants, from beans to datura to sunflowers. They don’t fly well, but they don’t have much need to fly either: they eat, they drop their eggs on the ground, their larvae mature underground, they come up and eat. And they eat a lot. They leave a tell-tale trail of skeletonized leaves. They also hang around however and their copper-colored, beautiful/scary shells glisten in the sunlight. More information about Japanese Beetles can be found here and here.

SFI believe that yards with no pests aren’t necessarily healthy. That’s the garden equivalent of white bread: a substance so lacking in nutrition that not even mold will grown on it. The presence of pests indicates a diverse environment that sustains a lot of varieties of flora and fauna.

Still, there are limits to how much of my garden I want to share and with whom.

dead Since we are committed organic gardeners, our preferred method of dealing with Japanese Beetles is picking them off. Jim is hardy enough to pick them off and squash them with his bare fingers! I’m always amazed by that. My method is perhaps less humane, although I don’t really think so. I fill a small plastic container with a couple inches of water and a squirt of dish detergent and then knock the Japanese Beetles (or other pests) into the water. They die instantly. Like other insects, Japanese Beetles have an escape technique: when they notice shadow approaching from above, they drop from the plant leaf. If you hold your dish under the leaf and come at them from above, most of the time they will drop straight into the pool of death. Sometimes, if they are busy munching on your plants, they might not drop and you’ll have to encourage them with a prod of the finger.

I know we’re not the only gardeners dealing with the Japanese Beetle plight. A quick perusal of other gardening blogs reveals a sadly similar tale: we’re all under attack. See here and here and here. It’s nice to know we aren’t alone.

This summer I’ve disposed of far more Japanese Beetles than in previous ones. I’m hoping for a good cold winter to lessen their population next year.

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