A siren call does in the Japanese beetle

I have just hung two bags out in my garden and, because of them, I expect to spend far less time than usual in picking Japanese beetles off my raspberry bushes and out of my roses.

The bags contain chemical attractants that apparently prove irresistible to the little marauders. They are lured to the traps from several hundred feet away which, for most of us, means that the moment a Japanese beetle crosses our property lines it should come within range of the siren call.

My optimism stems in part from the good things that Jim Willson, executive secretary of All America Selections, had to say of the trap and also because of the letter written to J. T. Baker Chemical Company, makers of the trap, by a satisfied user last year.

"I estimate that my four traps have collected in excess of 200,000 beetles in the last three weeks," an Ohio gardener wrote. "I base that on the fact that I collected, in one 48-hour period, 31,918 beetles.

"I arrived at this figure by using an electronic counting scale. I heartily endorse your product."

In an age when people are beginning to question the pesticide strategy that destroys almost everything else in the garden along with the pest, the Bag-a-Bug trap makes welcome news.

The trap has a specific target: Japanese beetles. Beneficial beetles, such as ladybugs, are no more drawn to the trap than the birds and the bees. Nor is any other insect, for that matter. In other words, if rose beetles are chewing on your prize specimens, don't expect the Japanese beetle trap to get rid of them.

Japanese beetles, as the name implies, are natives of Japan. They were imported -- quite accidentally, of course -- around 1916 when they first put in an appearance near Riverton, N.J. Natural enemies of the beetle didn't arrive with the original shipment so the beetles have spread largely unchecked since then.

One natural enemy of the beetle that has since been isolated in Japan and brought to the US is milky spore which attacks the beetle during the grub stage. It is spread over lawns where the adult beetle lays its eggs and is most effective.

Unfortunately, if you take the milky-spore route and your neighbor fails to do the same, his harvest of the metallic green beetles will fly into your yard next season; hence the value of something like the Bag-a-Bug trap.

The trap employs a sex attractant, or pheremone, and enough of the attractant is embedded in a one-inch-square adhesive tape to last all season. That takes care of the males. Both male and female beetles are drawn to the trap by the aromas released from a series of floral lures which are designed to appeal to the hunger instincts of both sexes. The floral lures, formulated to last 5 weeks in normal weather conditions, are contained in two small packets that come with the trap, providing a 10-week supply. In most cases this covers the Japanese-beetle season.

Place the traps in full sun some 30 feet away from the crop you want to protect. The idea is to lure the beetles away from the crop and not to it; thus , avoid placing the trap any closer.

As the attractants are aromatic, try to place the traps so that prevailing winds carry the scent toward the plants you wish to protect. This way feasting beetles will be drawn away, hopefully before they have done too much damage.

The attracted beetles are entrapped in a throwaway bag where they die. When full, simply dispose of the bag in the trash can and place another bag on the trap.

Meanwhile, if you still plan to go the old hand-picking route, it helps to know how the beetles escape from an attacker: they crawl to the edge of the leaf and tumble off, taking to flight once they have begun fallling.The trick is to hold one hand under the leaf while you try to pick the beetle off with the other. Chances are, if you miss with the one hand, the beetle will fall conveniently into the other.

Have a can of soapy water nearby so that you can dispose of the beetles caught in this manner.

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