Controlling Japanese Beetles

Use a properly installed trap to save your garden plants from this pest.

Have you observed a ½” long, copper-coloured beetle in your garden this year? You may have noticed the damage caused by this pest and did not realize the cause. Japanese beetles feed on the leaves of most garden plants, consuming the material between the leaf veins, leaving behind the lacy remains of formerly healthy plants. The scourge of Japanese beetles is being felt from the east coast through to Ontario and they continue to spread across the country. Just a few years ago this pest was restricted to areas well south of here but global warming has changed that. Japanese beetles have arrived with the opossum, on the back of milder winters. The question that most people ask is how to kill them.

The answer is that you don’t. You trap them.

The professionals in the pest control business figured out how to use the mating habits of the Japanese beetles against them. Much like the slug’s propensity for beer, we now have traps that employ the power of floral and pheromone lures for the adult beetles. If you can eliminate the adults, there will be no more babies. And the population of Japanese beetles declines sharply and quickly.

Available at garden-supply and hardware stores for about $20, the Japanese beetle trap is an odd-looking thing. When you bring one home from the retailer I encourage you to read the label, rather than just hang the unit in a tree near your prized roses. Little details like placing the pheromone capsule in the right way will make the difference between trapped beetles and a waste of your time and money.

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