How to Stop Fall Armyworms from Destroying Your Lawn and Garden
Now that you know what you’re dealing with, let’s explore the steps you can take to stop fall armyworms from decimating your lawn and garden.
1. Regular Lawn Inspections
Early detection is key to preventing severe damage. Make it a habit to inspect your lawn regularly during the late summer and fall months. Look for signs of caterpillar activity, including chewed grass blades, brown patches, and caterpillar frass (droppings) on the soil surface. If you suspect an infestation, perform the “soapy water test”: mix a bucket of water with dish soap and pour it over a small area of your lawn. Any armyworms hiding in the grass will be forced to the surface.
2. Natural Predators
Fall armyworms have natural enemies, such as birds, parasitic wasps, and beneficial nematodes. Encourage these predators in your garden by planting native flowers that attract birds and beneficial insects. Parasitic wasps, for example, lay their eggs inside armyworm larvae, effectively killing them before they can cause damage.
If you’re dealing with a minor infestation, leaving it to nature might be enough to keep armyworms under control.
3. Neem Oil and Biological Insecticides
Neem oil, a natural pesticide derived from the neem tree, can be effective in controlling armyworms. When sprayed on your lawn, it disrupts the pests’ feeding and reproductive cycles. This environmentally friendly option is particularly useful for gardeners looking to avoid chemical insecticides.
Alternatively, you can use Bacillus thuringiensis (Bt), a naturally occurring bacterium that targets caterpillars without harming beneficial insects. Bt works by infecting and killing armyworms after they ingest it, making it a targeted and safe solution for organic gardens.
4. Insecticide Applications
If the infestation is severe, chemical insecticides may be necessary. Look for products containing active ingredients like spinosad, carbaryl, or bifenthrin. These insecticides are effective at killing armyworms on contact. It’s best to apply them in the early morning or late evening when the caterpillars are actively feeding.
Make sure to follow the instructions carefully and apply the insecticide uniformly across the affected areas. In cases of heavy infestation, you may need to reapply after a few days to ensure all caterpillars are eliminated.
5. Watering and Mowing Practices
Proper lawn maintenance can make a significant difference in preventing fall armyworm infestations. Mow your lawn regularly to keep grass blades short, which makes it harder for armyworms to hide. Avoid overwatering your lawn, as armyworms are more attracted to moist, lush grass. Instead, water deeply but infrequently to encourage deep root growth, which makes your lawn more resilient to pest damage.
6. Reseeding and Lawn Repair
If your lawn has already suffered damage from armyworms, don’t panic. Reseeding the affected areas can help your grass recover more quickly. Use a high-quality grass seed that’s appropriate for your climate, and keep the soil moist until new growth appears. Fertilizing your lawn after armyworm damage can also help encourage regrowth.
Prevent Future Infestations
Once you’ve dealt with an armyworm invasion, you’ll want to take steps to prevent it from happening again next year. Here are a few preventive measures:
- Aerate your lawn: Aeration helps to reduce thatch buildup, making it harder for armyworms to find a place to hide.
- Use pest-repellent plants: Incorporate pest-repellent plants like marigolds, garlic, and lavender into your garden. These plants can deter armyworm moths from laying eggs in your lawn.
- Monitor your lawn in late summer: Fall armyworms tend to appear as the weather cools, so be extra vigilant during the transition from summer to fall.
Conclusion
Fall armyworms are a formidable foe, but with the right tools and techniques, you can protect your lawn and garden from their destructive march. Regular inspections, encouraging natural predators, using organic or chemical controls, and maintaining a healthy lawn are all key to keeping these pests at bay. So, as you prepare for the fall season, keep an eye on your lawn, listen for the silent march of those tiny boots, and be ready to act before the armyworms invade.
