Tuesday, November 17, 2009
(Top left - Snout nosed butterfly; Top right - Noctuid moth (armyworm moth); Bottom - fall armyworm) (All photos by Bart Drees, http://insects.tamu.edu/fieldguide)
Call it coincidence, but the snout nosed butterflies and army worms are not the same animal. Snout nosed butterflies emerged a month or so ago with avengence and have been seen around town since. They seem to prefer native grasses to find pollen, but are considered benign insects. Army worms just so happened to explode around the same time. Many people have confused the two for the same species, but they are very different.
Army worms become a small, brown moth. About the size of a penny. Snout nosed butterflies are butterflies, have more coloration and are not the agricultural pest that army worms are known to be.
You have have noticed army worms stripping down fields, all the way to the soil in some situations. Whether or not to treat is situation depended. How much will it cost you? Will the crop grow back in time for your purposes? How bad was the damage? Etc, etc.
There is no need to worry about snout nosed butterflies. If they emerge again in the spring or next fall, it does not mean that an army worm infestation will happen again.
In addition, army worms are known to be turf pests, but if you haven't seen them on your lawn yet - don't treat. The army worms that the media has been talking about and we have been getting calls on at the Extension office are agricultural pests.