Traditionally, the prices farmers receive for growing corn and soybeans has been low, but high yields and large acreages have provided for a small margin of profit. Now, corn and soybeans prices are at record highs, but input costs have risen dramatically. The potential for profit is very high but one or two bad input decisions can quickly wipe out that potential.

After a very slow start the growing season is underway. Corn has emerged across the area and those lucky enough to get some beans planted will soon be seeing soybean seedlings too. While waiting for field conditions to be suitable for bean planting, I recommend scouting your corn fields. Many of these fields have been emerged for almost two weeks, but have grown very little due to the cool weather. This puts the seedlings at a higher risk of insect and disease damage.

Reports are starting to come in about black cutworm activity. Several species of cutworms attack corn. The black cutworm found in corn will usually be from 1/2 inch to 1 1/2 inches long and may be from a light grayish brown to almost black. Although this species has several generations per year, seedling corn is most susceptible to damage..

Factors that may favor black cutworm outbreaks include late planting, broadleaf weed infestations occurring prior to tillage and planting, reduced tillage, and corn following soybeans.

When we think about cutworms scouting for cutworms we normally focus on looking for cut or missing plants, but the first stage larvae feed on leaves. Check fields for leaf-feeding by small larvae, cut, wilting, and missing plants. Examine a minimum of 250 plants (50 plants in each of 5 locations) in a field. When damaged plants are found, dig around the base of the plants for live cutworms. Sometimes the larvae will be found beneath clods, in the planter furrow, or in soil cracks.

A site-specific economic threshold combines larval size, corn size and the corn price to determine the value of a rescue treatment. The old rule-of -thumb is treatment may be needed if 3 percent or more plants are cut and larvae are still present. With today's prices this number probably needs to be lowered. A recent article from the Extension Entomologists at Iowa State suggest that for 4^th stage lavae around 3/4ths of an inch long the economic threshold would be around 1 percent stand loss. This may be very hard to detect. These medium sized worms can still cut several plants. In past if you have found worms that are over an inch long we have advised that they are nearly finished feeding and treatment would not be warranted unless damage was over 5percent plants cut. The higher prices shift the economic threshold down to 2-3 percent plants cut.

You can keep up to date on agronomic and pest information by reading the weekly "Bulletin" from University of Illinois Extension. You can read it online at http://www.ipm.uiuc.edu/bulletin/ you can also subscribe for free to the email edition or for $55 to the mail edition. If you need a good scouting reference I highly recommend the University of Illinois Field Crops Scouting Manual (X880d) available for $60. You can go through your Extension Office or call (800) 345-6087