Army worms can cause serious lawn damage fast– often in just a few days. If you’re seeing strange brown patches or caterpillars crawling through your grass, you might be dealing with an army worm infestation. Let’s walk through what to look for and how to treat them before things get worse.
What Are Army Worms?
Army worms are caterpillars that turn into moths. They’re called “army” worms because they travel in groups, eating everything in their path.
- Most active in late summer and early fall
- Thrive in warm, humid areas across the U.S.
- Feed on grass, especially newly growing turf
- Can destroy a lawn in just a few days if not treated
Photo Credit: Aggie Turf
Signs of Army Worms in Your Lawn
Visual Indicators
One of the first signs of army worms in your lawn is unusual browning or thinning grass that seems to spread rapidly. If you look closely, you may also see small, striped caterpillars—typically green, brown, or black with white or yellow lines running down their bodies.
Here are other tell-tale signs:
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Grass blades that appear chewed or ragged
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Patches of grass that look scalped or sun-bleached
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Visible caterpillars crawling on the soil or blades in the early morning or late afternoon
Photo credit: Harrells
Behavioral Signs
Army worms have specific habits that can help you catch them early:
- Most active early in the morning or just before sunset
- Hide in the soil or thatch during the heat of the day
- Damage often appears overnight
Pro Tip: Try the “soap flush” test – mix water with a little dish soap and pour it over a small section of your lawn. If army worms are present, they’ll come to the surface.
Lawn Pest Management: Why It’s Important
Managing army worms (and other pests) is key to keeping your lawn healthy:
- Army worms can destroy healthy turf in just a few days
- Damage leads to costly repairs and reseeding
- A strong lawn is better able to resist future pest problems
How to Treat Army Worms in Your Lawn
You may be wondering how to get rid of army worms in your lawn on your own.
Organic Treatment Options
Want a natural solution? Try these eco-friendly methods:
- Beneficial bugs like parasitic wasps or nematodes can help reduce army worm populations
- Neem oil or insect-killing soaps can be applied to affected areas
- Bacillus thuringiensis (Bt) is a naturally occurring treatment that only targets caterpillars
General Treatment Tips
- Mow the lawn before treatment to help products reach the soil
- Apply treatments early in the morning or late in the day when worms are feeding
- Water your lawn lightly before and after treatment, as directed
If DIY isn’t your thing, consider hiring a local lawn care professional to treat and monitor your yard.
Lawn Care Tips for Prevention
Once army worms are gone, prevention is your best defense.
Proper Watering Practices
- Water deeply but less often to encourage strong roots
- Avoid frequent, shallow watering—it promotes weak turf and pest problems
Fertilization Techniques
- Feed your lawn regularly with a slow-release fertilizer
- Don’t over-fertilize—lush, tender grass growth attracts pests
- Follow a seasonal lawn care schedule for your area
Conclusion: Maintaining a Healthy Lawn
Army worms can cause a lot of damage, but with the right plan, you can stop them in their tracks.
Here’s a quick recap:
- Watch for brown patches and caterpillars
- Use natural or professional treatments quickly
- Strengthen your lawn with proper watering and fertilizing
With consistent care and pest monitoring, your lawn can stay healthy, green, and army worm-free all season long.
Need a hand?
If you think army worms might be invading your yard, don’t wait!
Reach out to our team to schedule an inspection or treatment. GreenGate’s Sod Web Worm treatment also covers Army Worms.
