Cornell Cooperative Extention Reports Armyworms Found in NY Crop Fields


        Regional field crop specialist Kevin Ganoe of Cornell Cooperative Extension's Central New York Dairy and Field Crops Team reports that armyworms have been found in the area and field crop growers should be scouting their fields.

        Ganoe encourages that "Growers need to check their fields as armyworms can be locally heavy.  If you wait to hear of them being near you before you look you will be too late." He continues, "we hear of severe armyworm damage in Western NY this week but we have yet to see that type of severe damage here in Central NY. We have had damage here but it has been more limited."
Fields that are typical places for armyworms:
  • grass or mostly grass hayfields especially those that are now second cutting fields and you may be looking at harvesting that second cutting soon
  • corn fields that were late planted into grass fields, notill or tilled ground or fields planted into small grain cover crop.
  • corn fields with grassy weeds, quackgrass and other perennials or even annual grasses like crabgrass.
  • small grain fields       
Look for armyworms to be on the ground and undercover during the day, they feed at night.  They won't be in the ground but under any material they can find to crawl under. Armyworms may also be found in the whorl of corn plants feeding.  Armyworm larvae are a light grey on their underside with black and grey/blue striped sides and top.
Consider treatment if grass hay fields have a consistent population of 3-5 armyworms per square foot range.  Don't just look in one spot, you may find 5 and then look other places and find none. Recommendations in corn are for at least 3 per plant in the whorl and they are less than ¾ of an inch then consider treatment.  There is no reason to treat in preventative fashion for armyworms if they are not present.  Treatment will be more effective on armyworms that are less than ¾ of an inch long.
Kevin H. Ganoe
Central New York Dairy & Field Crops Team
Cornell Cooperative Extension Regional Field Crop Specialist

5657 State Route 5
Herkimer, NY 13350
Phone: 315-866-7920, ext 230
Cell: 315-219-7786
FAX: 315-866-0870