The North Carolina coast is a favorite stomping ground for fall armyworms and, when left untreated, these invaders can wreak havoc on your lawn. True to their name, armyworm larvae move in large numbers, or “armies,” feeding ravenously on grass along the way. The larvae then dig into the surface of the ground and emerge several weeks later as a moth.
Early detection is key in avoiding a total takeover. One moth can lay hundreds and hundreds of eggs at a time, creating a seemingly endless cycle of new larvae. If left untreated, fall armyworms can cause serious damage to established grass, and can even kill newly planted sod.
But don’t worry – Turf Medic’s got your back! We’re here to share some ways you can stop armyworms in their tracks, protecting your lush fall landscape. Rally the troops and get ready to start your defense!
Know The Signs
Because preventative and early treatment is key, identifying and recognizing early warning signs of fall armyworms is important. There are a few ways to spot these invaders.
Look For Identifying Characteristics
The fall armyworm lifecycle moves from egg to larvae to pupae to moth. Egg masses are typically found on plants, around the sides of buildings, and bordering turfgrass. They hatch as larvae, which can be identified by the following characteristics:
- 1 to 1 ½ inches long and green, mottled brown, or black in color
- Wide black stripe running down each side of the body
- Light-colored upside down “Y” marking on the head
Adult moths are more difficult to distinguish but can often be identified by a distinctive white spot on the center of the front wings.
In addition to looks, you may also notice greenish-black fecal pellets on the surface of soil or an excess of paper wasps and birds, as both feed on fall armyworms. If you’re having a tough time getting a good look, Turf Medic suggests bringing them to the surface of the soil with an easy-to-make solution. Simply mix 1⁄2 ounce of dish soap with one gallon of water and pour it over the area you think is infested.
Be On The Lookout For Damage
Armyworms have a wide range of hosts, but most often prefer cool season grasses like fescue, ryegrass, and coastal bermudagrass. Since eggs are usually laid around the edges of buildings or signposts, damage will often emanate from these areas.
Small larvae are generally responsible for “skeletonizing” the grass, while large larvae are known to devour the entire leaf or grass tissue. If you have an infestation, you’ll notice a distinct line between damaged and undamaged areas because of the larvae’s tendency to move as “armies.”
Prevent and Treat
Catching an armyworm infestation as early on as possible is extremely important in halting their invasion. Eggs and smaller larvae are generally easier to treat than large larvae. While the fall armyworm has a few natural predators that can help keep them in check, Turf Medic suggests chemical control as the most effective means to protect your lawn.
Consider these factors when applying pesticides:
- If possible, mow and lightly aerate your lawn prior to application.
- Apply insecticides late in the day, as fall armyworms are most active in the evening.
- After treating, don’t cut your grass for one to three days.
The size of the armyworms in your yard will help you determine what type of pesticide to use. Small armyworms can often be treated with insect growth regulator (IGR) insecticides, which like the name suggests, keeps the pests from growing and developing. For larger larvae, pyrethroid insecticides are a popular choice. This treatment, however, requires an applicator’s license. Alternatively, carbaryl and chlorantraniliprole do not require a license and can still be effective treatments.
Fall armyworms can be one of the most difficult types of caterpillar pests to treat, so don’t hesitate to bring in the Turf Medic team for reinforcement! We’re experienced in the most successful prevention and treatment techniques, giving you the upper hand against these destructive visitors.
Contact us today to make sure your lawn is defended against fall armyworms!