Record Numbers of Black Cutworm Moths

In this weekly Pest Watch update, you’ll learn the danger of letting black cutworms feed in your fields.

In this weekly Pest Watch update, you’ll learn the danger of letting black cutworms feed in your fields.



The Black Cutworm larvae are are light gray to black and about 1½" long when mature. Covered in convex skin granules, which gives them a shiny and greasy appearance.

Lush, green fields of winter annual weeds, as well as perfect rows of emerging corn, are the ultimate buffet for black cutworm larvae. Since both types of fields are prominent throughout the Midwest this spring, so are black cutworm moths.

John Obermeyer, Purdue University integrated pest management specialist, says his team has caught record amounts of black cutworm moths this year.

He says the moths are only the egg layers, but they are indicators of bad news. “The eggs hatch into larvae that are looking for something green to feed on.”

The larvae chew or “cut” (hence the name) leaves and stalks. If they cut below ground and reach the growing point, your crops are toast.

Listen in as Obermeyer discusses the pest:



Scout Soon for Black Cutworms

Because corn is the most vulnerable during emergence, Obermeyer says you should scout fields early. Also, if you use an herbicide to burn down the weeds, scout again. Once all the weeds are gone, the only green left to feast on will be your corn and soybeans plants.

According to the AgWeb Online Field Guide, the economic threshold for black cutworm damage is 3%, or when at least 2 out of every 100 plants are cut.


For More Information
Visit AgWeb Online Field Guide

Read:

Cold Weather Not Slowing Black Cutworm Moths




AgWeb-Logo crop
Related Stories
Agronomists explain why nitrogen must be present in the root zone well before the crop’s daily demand peaks.
Data shows late-planted corn can “cheat” the clock with GDU acceleration, making the case for holding the line on your original hybrids for now.
Given the weed’s yield-loss potential and long emergence pattern, farmers in its path are taking notice and putting control measures in place.
Get News Daily
Get Market Alerts
Get News & Markets App