Growing Concern For Insect Pests

As the month of July progresses, we have seen high insect populations and encourage you to scout thoroughly for western bean cutworm and western corn rootworm. We are also in the thick of county fair season, we would like to wish our growers the best of luck.

Western bean cutworm
In Northern Indiana, Northern Ohio, and most of Michigan, moth counts continue to be high and egg masses have been spotted. Egg masses can be found on the upper third of pre-tassel plants and are white, large, in appearance. This Michigan State University Extension article is a great resource for scouting and management of western bean cutworm. Treatment is warranted with heavy infestation of this pest. Please give us a call with any questions you have about western bean cutworm.

WBC Egg masses
Western bean cutworm egg masses pictured above.

Western corn rootworm
Corn goose necking has been spotted in the northern half of our footprint due to western corn rootworm larval feeding on roots. Western corn rootworm adults are yellow to green in color with a black stripe along the sides of their wing covers and about 5/16 inch long. Rootworm adults can be found feeding on leaf surfaces (they take off the “green”) and potentially in silks. Pay attention to silk clipping in pollinating corn. When selecting hybrids for 2018, we recommend choosing a hybrid stacked with the SmartStax® trait to protect from above- and below-ground corn insects.

Timing of fungicide applications
There is a great deal of variation in soybean growth stages due to prolonged planting. When timing fungicide applications, it is important to properly assess growth stage of the crop. At the R2 stage, the plant has one flower at one of the two uppermost nodes on the main stem with a fully developed leaf. Then at the R3 stage, the pod is 3/16 inch long at one of the four uppermost nodes on the main stem with a fully developed leaf. The R4 pod is 3/4 inch long at one of the four uppermost nodes on the main stem with a fully developed leaf. Each growth stage lasts for 8-10 days, depending on heat, etc. Our product guide has a diagram of soybean growth stages and Purdue extension does as well. If you are applying a fungicide on beans, consider variety, presence or absence of disease, weather conditions, etc. The most common time for application is around the R4 growth stage, but fungicide may be warranted anytime from R2 through R5. Call us to discuss your situation.

Let us know if you have questions while scouting your fields.

Terry, Rod, Dan and Dennis