Kevin Black, Growmark, has received many reports of burrower bug activity in cornfields and soybean fields south of Interstate 70 in Illinois and Indiana. Ron Hines, senior research specialist, Dixon Springs Agricultural Center, also has received many calls concerning these insects in southern Illinois. Ron indicates that as many as 10 to 15 burrower bugs per plant can be found in some soybean fields. In heavily infested areas of fields, plants are turning yellow.|
What are burrower bugs?
These small insects (less than 8 mm in length) look somewhat like stink bugs. They are slightly more oval than stink bugs and also have very small spines that protrude from their tibiae (lower legs). Most burrower bugs are black and found beneath objects such as stones, boards, and tufts of grass. They also may be observed commonly around porch lights in the evening.
How do they injure plants?
Like stink bugs and chinch bugs, they may injure plants by removing plant fluids with their piercing and sucking mouthparts. Damage is more likely to result if plants are under drought stress.
Are there any suggested economic thresholds or labeled insecticides for burrower bugs in corn and/or soybeans?
No. Because this insect is not a common pest, no thresholds have been established for either crop. In corn, injury to plants may resemble chinch bug feeding. No insecticides are labeled for burrower bug control in corn or soybeans.
Why are burrower bugs more numerous this year?
Like many of the relatively obscure insect pests that we've reported on in recent years, economic infestations of burrower bugs may be linked to earlier planting dates, milder winter conditions, cooler and wetter spring weather, a lack of natural enemies, or, more likely, a combination of these factors. I've never reported on burrower bug infestations, and it remains to be seen if these insects will become yearly pests.--Mike Gray