Management tips for corn earworm and western bean cutworm

decrease font size  Resize text   increase font size       Printer-friendly version of this article Printer-friendly version of this article

­­­­­­Corn earworms (CEW) are cannibalistic and normally only one will be found per ear. The pest is best identified by bright, variable color and a cuticle with an “unshaven” look. It will frequently be near the ear tip but may feed down the ear creating a track of damaged kernels. DuPont Pioneer experts warn the kernel injury creates an ideal environment for ear fungi to invade, leading to a quality problem at harvest.

Trapping and scouting – Light traps or pheromone traps can help determine when adults are flying. Scouting can be done in the field by looking for eggs on the green silks and turning back the silks at the tip of the ear to look for larvae.

Insecticide use – Because the larva is exposed outside the ear for only a short time, economical timing of insecticides is difficult. Stop insecticide application after silks turn brown.

Best management practices – Plant resistant hybrids and alter planting dates to avoid high densities of corn earworms.

Western bean cutworm (WBC) complete one generation of egg, larva, pre-pupa, pupa and adult per year. WBC adults (moths) are strong fliers, and are known to travel several miles. After mating, females deposit their eggs on the top surface of corn leaves in the upper one-third of the plant. Eggs hatch in 5 to 7 days, and larvae feed for 3 to 5 weeks as they develop through five instar stages. In early to mid-September, larvae complete their growth, stop feeding, and drop from the ear to the ground. They then burrow into the soil and construct an earthen cell for overwintering.

Trapping and scouting – Pheromone traps can be used to determine when and where to scout for adult egg laying. As soon as the first moths appear, immediately begin to scouting fields. Look for eggs and larvae on the upper leaf surface in the upper part of the plant. Sample 100 plants by checking 20 consecutive plants in 5 areas of the field, or 10 consecutive plants in 10 areas of the field. In variable fields, or with more hybrids planted, sample more areas of the field.

Insecticide use – When 8 percent of plants have an egg mass or young larva in the tassel, an insecticide application should be considered. This low threshold is necessary because larvae move between plants. Application timing is critical and multiple treatments may be needed.

Best management practices – Plant resistant hybrids to provide in-plant protection against WBC and eliminate the need for intensive scouting.

Buyers Guide

Doyle Equipment Manufacturing Co.
Doyle Equipment Manufacturing prides themselves as being “The King of the Rotary’s” with their Direct Drive Rotary Blend Systems. With numerous setup possibilities and sizes, ranging from a  more...
A.J. Sackett Sons & Company
Sackett Blend Towers feature the H.I.M, High Intensity Mixer, the next generation of blending and coating technology which supports Precision Fertilizer Blending®. Its unique design allows  more...
R&R Manufacturing Inc.
The R&R Minuteman Blend System is the original proven performer. Fast, precise blending with a compact foot print. Significantly lower horsepower requirement. Low inload height with large  more...
Junge Control Inc.
Junge Control Inc. creates state-of-the-art product blending and measuring solutions that allow you to totally maximize operating efficiency with amazing accuracy and repeatability, superior  more...
Yargus Manufacturing
The flagship blending system for the Layco product line is the fully automated Layco DW System™. The advanced technology of the Layco DW (Declining Weight) system results in a blending  more...
Yargus Manufacturing
The LAYCOTE™ Automated Coating System provides a new level of coating accuracy for a stand-alone coating system or for coating (impregnating) in an automated blending system. The unique  more...
John Deere
The DN345 Drawn Dry Spreader can carry more than 12 tons of fertilizer and 17.5 tons of lime. Designed to operate at field speeds up to 20 MPH with full loads and the G4 spreader uniformly  more...
Force Unlimited
The Pro-Force is a multi-purpose spreader with a wider apron and steeper sides. Our Pro-Force has the most aggressive 30” spinner on the market, and is capable of spreading higher rates of  more...
BBI Spreaders
MagnaSpread 2 & MagnaSpread 3 — With BBI’s patented multi-bin technology, these spreaders operate multiple hoppers guided by independent, variable-rate technology. These models are built on  more...

Comments (0) Leave a comment 

e-Mail (required)


characters left

Smooth Wall Grain Bins

Meridian’s SmoothWall bins are the ultimate storage bins, used to handle and store fertilizer, grain, feed and seed, and extend ... Read More

View all Products in this segment

View All Buyers Guides

Feedback Form
Feedback Form