Experts discuss how to rid your yard of armyworms

Experts discuss how to rid your yard of armyworms

BIRMINGHAM, AL (WBRC) - Homeowners put a lot of money and investment into their lawns to keep them beautiful. But some pests are doing a lot of damage right now.

Armyworms are destroying some lawns in Alabama. The worms come from moths that are carried by the wind from South and Central America.

This happens annually from August to November. You will notice some areas of your lawn browning.

"You will see that thin out over a period of a day or so. They do a lot of damage in a short period of time. So you have to inspect on almost a daily basis when we have an outbreak like we do now," Brian Ethridge with Wayne's said.

Armyworms are the larvae of a moth. The caterpillars are light green or tan in their early growth stage and dark green or brown in later stages.

Ethridge with Wayne's says his company is seeing number of homes dealing with armyworms. He suggests homeowners mow their lawns regularly and take quick action if they are spotted.

"If they are not treated within in the first 24 to 48 hours of finding those insects then you can have lawn completely stripped down to nothing but stems which looks like it's dormant in January," Ethridge said.

Bottom line: if you think you have a problem, contact your pest control company like Wayne's or some other group. Try to take care of your investment and they will take care of the problem.

The Alabama Cooperative Extension System (ACES) says a sweep net is an affordable way to find armyworms and can be borrowed at many extension county offices. If you find more than two armyworms per square foot of yard when using the sweep net, they recommend cutting your grass and applying an insecticide.

ACES says an insecticide applied before the armyworms molt into their last stage will be more effective. For a longer-lasting insecticide, look for the active ingredients Prevathon, Intrepid and Dimilin. If you're buying an insecticide in a retail store, make sure to consult the individual labels to a formula that can target armyworms.

ACES offers these further tips if you're treating your lawn yourself:

  • Cutting turf prior to treatment aids in control because the insecticide will not have to penetrate as far to reach the armyworms.
  • Irrigate lightly prior to treatment. It has been shown to help in some cases because it may increase the larval activity.
  • Apply treatments in the early morning or late afternoon when they are most active.

More tips from Planet Natural's website:

  • Avoid using harmful pesticides or practices that would inadvertently destroy beneficial insects, your first line of natural defense.
  • Use pheromone traps to monitor the arrival of moths. When you first notice them — look for the distinctive white dot on their forewings — it’s time to start closer inspection of your plants.
  • Look for larvae and signs of damage beginning in early spring. Caterpillars will often be found feeding on the undersides of leaves and on new growth. Handpick the worms you discover and don’t be tempted to crush them between your thumbs. Instead drop them in a bucket of soapy water.
  • Release trichogramma wasps to parasitize any newly laid eggs. These tiny beneficial insects — 1mm or less — insert their eggs inside of pest eggs, killing them before they enter the plant-eating larval stage.
  • Other beneficial insects, such as lacewing, ladybugs and minute pirate bugs feed on armyworm eggs as well as the young larval stage. Remember: beneficial insects help control other harmful pests, including aphids, earworms, cutworms, cabbage loopers, a variety of mite and insect eggs.
  • Plant to attract birds and beneficial insects. Birds are especially fond of the moths and will pull larvae from lawns and plants. In the fall, uncover and turn your soil before putting it to bed, giving birds a chance to pick off the exposed pupae.
  • If you’ve had an infestation or are otherwise worried that conditions, including a cool, wet spring, will encourage the worms, release beneficial nematodes into your soil. These microscopic soil creatures feed on the eggs, pupae, and larvae of some 200 pests. They will not harm vertebrates, whether human or amphibians, will not harm plants, honey bees or earthworms and won’t threaten beneficial insects who, like the trichogramma wasp, lay eggs in something, not just anywhere in the dirt. Yet beneficial nematodes are murder on army worm eggs and pupae found in the soil.
  • After the season has advanced, natural horticultural oil sprays can be used on plants showing signs of worm infestations. Multi-purpose neem oil spray is effective on various stages of the larvae as well as mites. It also prevents fungus growth. Complete coverage, including undersides of leaves and junctions with stems, is critical.
  • Applications of Garden Dust (Bt-kurstaki) or OMRI-listed Monterey Garden Insect Spray (spinosad) will also kill caterpillars. Use organic insecticides if pest levels become intolerable.

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