However, you may want to pay attention to the damage this fall and take action next year.
On a recent conference call, Dr. Dave Shetlar, Ohio State University Extension entomologist, provided some great information on the current situation of Japanese beetle and other grubs.
One of the most common comments from homeowners that have grub damage in their lawn is that they didn’t see that many Japanese beetle adults this summer. Dave noted that we also have other beetles that lay eggs that lead to grubs in lawns that cause damage.
Entomologists have seen increasing populations in the Northern masked chafer and the Asiatic garden beetle. The larvae of these beetles can cause damage to turf. We are also seeing increased populations in green June beetles, but their larvae do very little to damage turf.
Interestingly, populations of Japanese beetles have really crashed in the past 10 years, not just in the Miami Valley area but in Ohio in general. Entomologists are scratching their head as to why this has occurred.
On the other hand, people in Kansas and Nebraska are fighting the front line, as Japanese beetles are now moving into these areas.
Dave noted that we are seeing localized populations of Japanese beetles. I heard from gardeners in the Centerville and Springboro area earlier (July) that they are seeing significant populations in these communities.
Beetles need good soil moisture in July and August when they are laying eggs in order for the eggs to survive. If you recall, we had periodic rain events, especially in July, that kept the soil moist. This is one of the main reasons why we are seeing good populations of grubs.
One of the other complaints that I am hearing from gardeners is that they applied grub control products in the early spring and they are not working. Depending on the product applied, this may very well be the case.
Products containing imidacloprid that were applied in May probably ran out of steam and did not work. These products should be applied in June, July and early August.
Products that contain acelepryn probably did a good job of controlling grubs this year. This has a longer residual and can be applied in early April and still have good control in the later summer.
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