Japanese Beetle

   Courtesy of Department of Entomology,
                Iowa State University,
Japanese Beetle


Did you get Japanese Beetles last year? May or June Beetles? Cucumber Beetles? You can control these pest beetles all season long without having to work so hard keeping them away! But you must prepare early!


In May and June throughout most parts of the country, the Japanese and May/June beetles will begin emerging. Larvae (sometimes called the "White Grubworm") have been overwintering in your soil – munching on roots and generally having a grand old time under your roses. Most species of the Cucumber Beetle overwinter as adults. When warmer temperatures arrive this spring, they lay eggs for the summer’s offspring. The larvae of the Cucumber Beetle are also known as the Corn Rootworm and no less than six species are found throughout the North American continent. All these beetle pests love your rose garden and can decimate foliage, blossoms or both!

If you had pest beetle problems last year, you can minimize their presence this year by applying beneficial nematodes to your garden and roses. Watering the nematodes into your soil as soon as the soil temperatures warms up.

Sold by many nurseries, home improvement centers, insectaries and mailorder firms, these products come under a variety of brand names. The "active ingredients" to look for are a species of micro-worms which either go by the name Heterorhabditis or Steinernema. Some products contain a blend of both micro-worms.

These micro-worms are harmless to humans, our pets and our roses. But they devastate soil borne pest larvae and eggs (including those of the Harvester Ant, Southern Fire Ant, and Leaf-cutting Ant).

Oh! By the way, if you continue to use diazinon or chlorpyrifos lawn insecticides, you will kill these beneficial critters along with your pest grubs.
By Mark Whitelaw, Kindly Provided by Laura Whitelaw

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