ST. LOUIS COUNTY – It’s a problem Missouri homeowners don’t typically have to face but lawn care companies have been getting many calls about armyworms. Some homeowners across the region have been noticing their grass turning brown late this summer and early meteorological fall, but not due to the heat stress of the late August days.
A good indication that there’s a problem more than just typical heat stress is the grass that’s turning brown despite proper irrigation. This could be a sign you have armyworms.
Ryan Lawn and Tree have seen calls ramp up over the past two to three weeks with homeowners noticing their yards taking a turn for the worse.
Craig Calhoun, a turf manager with Ryan Lawn & Tree, says these armyworms typically don’t make it up this far north but this year they’ve made it all the way to Michigan.
The last time we had issues in St. Louis was in 2017. Since it’s not a yearly occurrence, lawn care companies don’t automatically treat them.
These armyworms feed on your grass doing damage and turning it brown. The good news, if you catch it early enough, with proper watering after treating your lawn with an insecticide, the grass should grow back just fine.
However, the damage from these worms leaves the crown, or base, of the grass exposed to the elements. Your grass is then more susceptible to heat stress and that can, in turn, kill it.
“This year, we had a lot of storms come out of the south and so they’ll get blown up here whether it’s in a wind storm or a rainstorm. Usually, they’ll make it to your Oklahoma or a little bit further south from here but not very often will they make it this far north,” said Craig Calhoun, a turf manager with Ryan Lawn & Tree.
“If we’re not watering or catching the damage quick enough that soil will heat up causing the grass plant to die. Armyworms don’t necessarily kill the yard it’s more of the conditions that will kill the yard.”
The good news is that these armyworms won’t stick around for long. Missouri’s cold winter will kill them off and they hopefully won’t return again next year.