Western Bean Cutworm Flight Is Beginning And Concerns For Late Planted Corn

Jul 06, 2016

Here comes another season of western bean cutworm trapping! Western bean cutworms (WBC) emerge as adults from late June until August, with peak flight usually occurring the 3rd week of July. After mating, they lay eggs in corn, and the developing larvae may eventually enter the ear to cause significant ear damage. While our trap catches have increased slightly over the past few years, we have been noticing an increase in damage, some of which may be economic. WBC prefers to lay eggs in pre-tassel corn—so any corn that does not develop tassels over the next 2 weeks is at high risk for western bean cutworm infestation. We have a lot of late planted corn, so good scouting is important!

Egg masses are the most important stage to scout corn. Eggs are laid on the upper surface of the top 1-3 most leaves, especially those still in the vertical position. Egg masses are usually in clumps of 25-100, start out white, then, within 24 hours of egg hatch turn dark purple. After hatching, the larvae will feed on the tassel and pollen before entering the ear. Once they enter the ear, they are mostly protected from insecticides, so spraying, if necessary should occur after egg hatch. Thresholds are based on inspecting 20 plants in 5 locations, and if 5-8% of the corn has egg masses, treatment is necessary. Many insecticides have efficacy against WBC. Furthermore, Bt products with Cry1F or Viptera will provide control; however we have noticed a fair amount of feeding with Cry1F in our trials. While it may protect against economic losses, these fields should be scouted as well.

Source:osu.edu

Video: Residue Management

Residue Management conservation practice manages the amount, orientation, and distribution of crop and other plant residue on the soil surface year-round while limiting soil-disturbing activities used to grow and harvest crops in systems where the field surface is tilled prior to planting. This video explores how Ryan McKenzie implemented this conservation practice on his farm in Samson, Alabama.

Practice benefits:

• Increases organic matter

• Improves air quality

• Decreases energy costs

• Reduces erosion

• Improves soil health

The Conservation at Work video series was created to increase producer awareness of common conservation practices and was filmed at various locations throughout the country. Because conservation plans are specific to the unique resource needs on each farm and also soil type, weather conditions, etc., these videos were designed to serve as a general guide to the benefits of soil and water conservation and landowners should contact their local USDA office for individual consultation.