Black Cutworm and Armyworm Caterpillars Should be Evident

Doug Johnson, Extension Entomologist, University of Kentucky

Our insect development estimator, using the insect trap captures as our Biofix and current temperatures from the Princeton weather station indicate that egg hatch has begun and small

caterpillars should be present. I have not yet found any armyworms, but cutworm caterpillars have been detected in some tobacco float beds. This is a small, but timely indication that our temperature driven estimations are on track. Producers, consultants and scouts should begin looking for armyworm and cutworms in various crops including small grains, corn, tobacco and forage grasses.          WARNING--- we are still a bit on the early side so most of the caterpillars may still be quite small. Cutworms large enough to cut plants may take several more days to a week before they are evident.  Armyworms especially will avoid bright sunny conditions so one should scout in the early AM or late PM, in dense growth, and especially under surface litter remaining from last year’s crops.

Once again, remember my estimates are based on insect capture, and temperatures from the traps and weather station at Princeton (Caldwell Co.) KY. Other locations will vary due to differences in location. I do know that Leann Martin’s Logan Co. armyworm traps, though not capturing quite as many AW as the Princeton traps, still consistently caught more AW moths than would have been predicted by our rolling five-year average.

 Kevin Knop has three  BCW traps out in Wingo & Hickory, KY and Martin, TN that have consistently been a bit on the low side compared to the Princeton rolling five-year average (CAREFUL!  he is using a different trap than the Princeton & Logan Co. UK sites). The UK-IPM BCW trap in Lexington, Ky is still quite a bit above the rolling five-year average, so arrival of caterpillars in central KY will be a bit later. Nevertheless it is a good time to start scouting!

Remember these model estimates are a matter of increased or reduced risk. They are not exact.