Asiatic garden beetle in corn

Ron Hammond, Andy Michel, Ohio State University  |   May 29, 2013 

Asiatic Garden Beetle Grub

 Last spring at this time, Ohio State University researchers mentioned a new corn pest that had appeared in extreme northern Ohio: grubs of the Asiatic garden beetle. This pest had been found as a newer corn pest in northeast Indiana and southwest Michigan around 2006-2008, always in sandier soils and following soybeans, both conditions which were met in Ohio last year. The researchers' concern was that this grub is considered very aggressive in its feeding habits, and thus, is much more damaging than most other grubs.

Grubs of this species are smaller than other grubs likely to be found, such as true white grubs and Japanese beetle grubs. The main characteristic that can be used to identify them are the enlarged maxillary palps on the side of their mouthparts.

Of concern right now is that stand losses from this grub have been found in corn fields in Tuscarawas County, south of Canton, Ohio, much farther south than expected to ever be found. The problem fields are in sandy soils in a lower river bottom area. Researchers recommend growers throughout the state check corn in sandy soils, particularly paying attention to fields in river bottom areas where sandy soils are often found.

If grubs are located, please contact hammond.5@osu.edu, or else send them to him via your Extension educator. Place them in a container with moist soil for shipping. Because they would like to hear of any stand reductions by any and all grubs, please collect any grubs that are present so they can be correctly identified. But the researchers especially need to determine other areas of the state where the Asiatic garden beetle is causing stand losses to corn. At the present time, similar to other grub problems, there is not a rescue treatment available, and the only action would be replanting if necessary. Remember that most of the grubs should be pupating shortly.