KNOXVILLE, Tenn. (WATE) — They’re small, with a big appetite and not to mention, they’re eating their way through lawns and gardens throughout the region — they’re called fall armyworms.

They’re a species of caterpillar from the Caribbean. They usually migrate from central America to southern states such as Texas and Florida. They thrive in hot, tropical climates. This year, residual rain and winds from Hurricane Ida brought them even further north to Tennessee. The worst part — they’re turning luscious green lawns brown, which is impacting some lawn care businesses.

Collis Lowe, owner of Hardin Valley Lawn and Landscape and Civil Works LLC said, “I had a phone call from one of our clients saying they’re yard was turning brown and I was wondering well we just had a lot of rain so it can’t be from dehydration of the soil or anything like that.”

The soil wasn’t dehydrated, it was digested, and Dr. Frank Hale, professor of Entomology at the University of Tennessee said, “This particular type of armyworm is called the fall armyworm. They generally have some kind of dark and light stripes on them. They’re not a fuzzy caterpillar. They can get to an inch, inch and a half long when fully mature.”

Lowe says his crew have had to skip some houses on their routes due to the yards being absent, and replaced with stretches of brown land.

“What happens is the armyworms eat the grass and shrink it down and it becomes like a mud slick,” Lowe said.

They’re not harmful to humans, but they will destroy your lawn, garden and other crops.

Lowe said, “Hayden Hill and Hardin Valley had a huge infestation of them. I would say 75% of our clients in there were hit by armyworms.”

The insects thrive in hot, tropical climates — they usually migrate from Mexico and the Caribbean to Texas and Florida. This year, residual rain and winds from Hurricane Ida brought them even further north to Tennessee.

Dr. Hale said, “Everything was ideal and so, we had an unprecedented infestation in Tennessee.”

Now, instead of mowing lawns, this company is replacing them. Hardin Valley Lawn and Landscape has started offering a discount to replace sod on lawns that have been eaten by the Fall Armyworms. Their information can be found here.

Entomologists say catching them early is key. “They’re easier to kill when they’re in those early stages,” Hale said. “If you wait until they’re bigger they’re more difficult to kill and they’ve already done damage.”

On the bright side, if you’ve been impacted, your grass should grow back.

You can check your lawn before it gets destroyed — mix a small amount of dish soap with a gallon of water and pour it over a 4 sqft area of grass. The mixture will irritate the insects and they will come to the surface of the grass. You’ll be able to see if you have fall armyworms in their early stages.

If you have Fall Armyworms, it’s recommended to call a pest control service or lawn service to spray insecticides to get rid of them.