Black Cutworm Moths Abundant And On The Move

URBANA, ILL.

   Over the past several weeks, black cutworm moths have been captured in pheromone traps by cooperators throughout much of Illinois. This is not surprising given the significant winds from the south and southwest throughout much of March that resulted in record breaking warmth for the month. This pattern has persisted into early April, and consequently many fields across southern and central Illinois have been planted and are beginning to emerge. Corn in the 1- to 4- leaf stages of development is most susceptible to cutting by black cutworm larvae.

   I urge producers to look for early signs of leaf-feeding injury that could signal potential cutting of plants by black cutworm in the near future. Even if you planted a Bt hybrid, don’t be lulled into complacency. Under heavy infestations, control afforded by some Bt hybrids may be inadequate. Intense captures of moths (9 or more caught over 1 to 2 days) were reported by University of Illinois Extension’s Dale Baird (Lee County) on March 24 and John Fulton (county director, Logan, Menard, and Sangamon counties) on March 30. Jim Morrison, a retired crop systems extension educator, reported 16 moths were caught on April 2—the earliest and most significant capture in many years, he noted.

   Fields most at risk for black cutworm injury include those heavily infested with winter annual weeds. Favorite weed targets for egg-laying black cutworm moths include mouse-eared chickweed, bitter cress, shepherd’s purse, yellow rocket, and pepper grass.

   I encourage you to visit the North Central IPM PIPE web page at apps.csi.iastate. edu/pipe/?c=entry to view captures of black cutworm moths that cooperators have reported. Kelly Estes, state survey coordinator at the Illinois Natural History Survey, coordinates the collection of these data. She says that trapping will be reported at the website throughout the summer for additional insect pests, including European corn borer, corn earworm, western bean cutworm, and fall armyworm. For more information about the biology and life history of the black cutworm, along with scouting procedures, please see extension. cropsci.illinois. edu/content/ black-cutworm. Δ

DR. MICHAEL GRAY: Professor Crop Sciences, University of Illinois

Seedling stage corn in the 1 to 4-leaf stage remains susceptible to cutting by black cutworms (Champaign County, April 4).

Fields infested with winter annual weeds aremost susceptible to egglaying by black cutworm moths (Champaign County, April 4).