No Black Cutworm Activity Reported Yet…Very Little Corn Either

Multiple intensive black cutworm moth captures, 9 or more caught over a 2-night period, around April 12, signaled for us to begin tracking heat units (Base 50), see “Black Cutworm Pheromone Trap Report.” Based on the black cutworm’s growth development model, it takes approximately 300 heat units (base 50ºF) from egg hatch to early 4th instar; this is when black cutworm larvae begin to cut plants. Some minor leaf injury may be present before then.

In referring to the accompanying temperature accumulation map, the southern third of Indiana is currently at, or above, 300 degree days. With forecasted warmer temperatures, soon all of southern Indiana should be scouting for black cutworm feeding/cutting in high risk corn. Unfortunately, less than 10% of the corn is planted, and weedy fields for egg laying are abundant for continual moth arrivals. Consider the timing of corn emergence, yet to be planted, and the progression of cutworm development in the next week or two.

Happy scouting!

Heat Unit (base 50)

 

Black cutworm instars (i.e. size) 2 through 6, 4th instar is left of the penny.

Black cutworm instars (i.e. size) 2 through 6, 4th instar is left of the penny.

Share This Article
It is the policy of the Purdue University that all persons have equal opportunity and access to its educational programs, services, activities, and facilities without regard to race, religion, color, sex, age, national origin or ancestry, marital status, parental status, sexual orientation, disability or status as a veteran. Purdue is an Affirmative Action Institution. This material may be available in alternative formats. 1-888-EXT-INFO Disclaimer: Reference to products in this publication is not intended to be an endorsement to the exclusion of others which may have similar uses. Any person using products listed in this publication assumes full responsibility for their use in accordance with current directions of the manufacturer.
Pest&Crop newsletter - Department of Entomology Purdue University 901 W. State St. West Lafayette, IN 47907

© 2020 Purdue University | An equal access/equal opportunity university | Copyright Complaints | Maintained by Pest&Crop newsletter

If you have trouble accessing this page because of a disability, please contact Pest&Crop newsletter at luck@purdue.edu.