Home / Crops / Corn / Corn Production / Black cutworms found in Iowa; focus turns to scouting

Black cutworms found in Iowa; focus turns to scouting

Agriculture.com Staff 05/22/2007 @ 8:25am

Black cutworms that were causing economic damage to corn fields in the central and eastern Corn Belt last week are heading west.

Agronomists with Pioneer Hi-Bred International, Inc., confirmed that heavier-than-normal cutworm moth flights this spring have materialized into larvae populations in the southeastern part of Iowa, where agronomists have observed "scattered cuttings." In 2006, Jasper, Poweshiek and Keokuk counties in Iowa saw heavy infestations, according to Pioneer.

Last week, Pioneer and University of Illinois officials confirmed black cutworm cutting underway in Illinois. There, agronomists said cutworm moths likely rode stronger-than-normal southerly wind currents earlier on in the spring.

Field scouting for the pest is now the top priority for black cutworms in the affected areas. By carefully scouting, University of Illinois Extension entomologist Kevin Steffey says growers can get ahead of serious cutting damage -- especially in younger corn plants -- by watching for leaf-feeding.

"Be prepared, especially in areas where corn has yet to be planted or has just gone into the ground," Steffey says. "Populations of black cutworms will only increase as moths continue to fly...but even in areas with corn emerging, be sure to check fields for black cutworms and symptoms of their feeding injury.

"Leaf-feeding injury is not economic, but it is a precursor to stand-reducing cutting damage."

In scouting, however, Steffey says it's important to distinguish between black cutworms and other species that cause little or no damage, like the dingy cutworm. According to Iowa State University entomologist Marlin Rice, there are a few characteristics of dingy and black cutworms that should set them apart in scouting fields.

"Black and dingy cutworms are separated by two distinctive features: Skin texture and relative tubercle (wart) diameter. Blacks have grainy skin like sandpaper, whereas dingys have smooth skin. You will need a good hand lens to see this feature," Rice recently wrote. "Identification also is based on the size of the four tubercles along the top center of each body segment. On the dingy cutworm, these tubercles are about the same diameter. On the black cutworm, the inside pair of tubercles (or the pair closest to the head) is about half the diameter of the outside pair."

Black cutworms that were causing economic damage to corn fields in the central and eastern Corn Belt last week are heading west.

CancelPost Comment
MORE FROM AGRICULTURE.COM STAFF more +

Farm and ranch risk management resources By: 07/07/2010 @ 9:10am Government resources USDA Risk Management Agency Download free insurance program and…

Major types of crop insurance policies By: 07/07/2010 @ 9:10am Crop insurance for major field crops comes in two types: yield-based coverage that pays an…

Marketing 101 - Are options the right tool… By: 07/07/2010 @ 9:10am "If you are looking for a low risk way to protect yourself against prices moving either higher or…

MEDIA CENTERmore +
This container should display a .swf file. If not, you may need to upgrade your Flash player.
Cool Tools Christmas Edition: Part 2