Armyworms are invading the area, and are causing extensive damage to some crops and lawns.

According to Nick Seiter, Research Assistant Professor, Field Crop Entomology
Department of Crop Sciences with the University of Illinois, the worms tend to feed on different grasses such as alfalfa, hay, and pasture, as well as lawns. However, Seiter notes there is some concern this year for late soybeans.

(Department of Crop Sciences
University of Illinois)

He says the fall armyworm has arrived early and they’re not used to dealing with the large numbers seen this year.

Some lawn experts advise using a mixture of water and dish soap on lawns to see if armyworms have made their way into your lawn. That is if they haven’t eaten through it already. Lawn experts say the worms eat fast.

According to Seiter, depending on the crop, there are several insecticides that are effective.

He says one of the issues their colleagues in the south have run into is control difficulties with pyrethroids, which are among the most commonly used insecticides in soybean, pastures, and alfalfa.

He also advises in forages, early cutting can also help to mitigate the damage.

Armyworms are small – they’re about the size length-wise as a quarter. However, they can eat through a lawn the size of a football field in just three to four days.