FALL ARMYWORM

​Fall armyworms are a nationwide summer lawn concern, but the Gulf Coast and Southeast often see some of the earliest and most persistent activity. In Alabama, Mississippi, and the Florida Panhandle, warm temperatures and abundant summer moisture can create ideal conditions for populations to build quickly. As the season progresses, migrating moths can carry the problem farther north. 

If your lawn suddenly looks thinner, more ragged, or more damaged than it should this time of year, you may not be imagining it. Fall armyworms could be the culprit—and catching an infestation early can make a big difference in how quickly your lawn recovers.

What Is Driving Fall Armyworm Activity?

Fall armyworms do not typically survive the winter.  Instead, moths move northward from warmer areas and lay eggs when conditions become favorable. Warm temperatures, adequate moisture, and lush turf can create ideal conditions for populations to build quickly.

Once eggs hatch, the caterpillars can move through their life cycle in just a few weeks during hot weather. That means an early start can lead to multiple generations during the growing season—and potentially more pressure on lawns before fall arrives.

Warm, humid Gulf Coast summers provide exactly the kind of conditions that can accelerate this cycle. Lush, actively growing turf can be particularly attractive to young caterpillars simply because there is plenty of tender plant material available for them to eat.

Bermudagrass, St. Augustinegrass, zoysia, and centipedegrass can all experience fall armyworm damage, although the severity of the damage and the turf's ability to recover can vary by grass type and growing conditions.

How to Spot Fall Armyworm Damage Before It Spreads

Fall armyworms often feed in groups, and an infestation can progress surprisingly quickly. Larger caterpillars can consume significant amounts of turf in a short period of time, leaving areas that appear suddenly thin or brown.

Early damage can be easy to overlook. Young caterpillars may feed on the surface of grass blades, creating a “windowpane” or skeletonized appearance before larger, more obvious patches develop.

Watch for these warning signs:

• Small brown or tan patches that seem to expand quickly
• Grass blades that look ragged, notched, or translucent when held up to the light
• Birds gathering and feeding heavily in one area of the lawn
• Small green, brown, or tan caterpillars hiding in the thatch or near the soil surface
• More active caterpillars in the early morning or evening, when temperatures are cooler

One simple way to check for an infestation is to closely inspect the edges of damaged areas and the turf near the soil surface. You can also use a soapy-water flush to bring caterpillars to the surface, making them easier to identify.

The sooner you identify fall armyworms, the more options you have for managing them. Don't wait until an entire section of lawn has turned brown. Regularly walking your lawn and looking for early signs of feeding can help you catch an infestation while there is still plenty of healthy turf left to protect.

A little attention now can save a lot of lawn later.