Issue No. 4, Article 2/April 18, 2008
More Information About Armyworm and Black Cutworm Adults
The article about black cutworms in last week's issue (issue No. 3, April 11, 2008), especially my comments about trapping for black cutworms, elicited several useful responses. Because Kentucky and Missouri border Illinois on our south and west, networks of pheromone traps in those states could provide some useful "forecasting" information for Illinois. In the meantime, a small network of traps in southern Illinois is being prepared for operation in 2008, albeit a little late for some early-season moth flights. Nonetheless, eventually we will have traps erected for capturing adult armyworms, black cutworms, corn earworms, European and southwestern corn borers, fall armyworms, and Japanese beetles. The captures in these traps will once again be reported in "The Hines Report" on our IPM Web site. Within a relatively short time, the five sites for the 2008 traps will be changed from the six sites used in 2007. Ron is an employee with Growmark but has a "zero-time" visiting research specialist position with the University of Illinois. His organization of this network of traps will benefit many people, and we sincerely appreciate his efforts on behalf of crop producers in Illinois. University of Illinois Extension educators also are erecting or have erected traps for capturing a variety of insects, and results will be published as captures are reported.
The University of Kentucky IPM Web site includes counts of insects captured in Lexington and Princeton--Princeton being about 40 miles, give or take, due east from the southeastern tip of Illinois. Counts of armyworm adults in the Princeton trap have increased noticeably and are in line with the numbers of moths captured there in 2006 when an outbreak occurred. So wheat producers in southern Illinois should be on the alert for armyworm larvae soon. On the other hand, captures of black cutworm adults have been relatively low in both Kentucky locations thus far.
Steven Kirk, an Extension associate in IPM at the University of Missouri, sent information about their insect trap network, which can be viewed on the University of Missouri Plant Protection Programs Web site. Several of the Missouri trap operators have captured black cutworm adults already this spring, although for the most part the numbers captured have been small through the first week of April. The one exception was the capture of 18 moths on one night (April 11) in Missouri's Franklin County, roughly 50 miles west of Monroe County, Illinois. This represents an intense, or significant, capture (9 or more moths captured over one or two days), the biofix for beginning to accumulate degree-days above a base temperature of 50°F. It's also important to note that Dave Feltes, University of Illinois Extension IPM educator, captured four black cutworm adults in his trap in Whiteside County in northwestern Illinois on April 15.
Our advice for now: Given the later corn planting dates we anticipate in 2008 compared with the recent past, black cutworms could be a more widespread issue this year than in the past few years. People will have to sharpen their scouting skills and be prepared for frequent scouting trips to keep up with potentially rapidly developing cutworm larvae.--Kevin Steffey