Severe leaf loss exposes turfgrass crowns to direct sunlight and high temperatures making them susceptible to desiccation and death, so it’s important to control the insects before total leaf loss occurs.
A male fall armyworm rests on sedum.
Control
Armyworms can be controlled with contact insecticide spray applications using products such as those below.
• Azadirachtin: Azaguard Botanical Insecticide and others
• Bacillus thuringiensis: Dipel, Thuricide
• Bifenthrin: Ortho Bug B-Gon Lawn Insect Killer
• Deltamethrin: Hi-Yield Turf Ranger Insect Control
• Gamma-cyhalothrin: Spectracide Triazicide Insect Killer
• Imidacloprid + cyfluthrin: Bioadvanced Complete Insect Killer
• Permethrin: Hi-Yield 38 Plus Turf, Termite and Ornamental
• Spinosad: Captain Jack’s Dead Bug Brew, Fertilome Borer, Bagworm, Tent Caterpillar and Leafminer Spray
• Trichlorfon: Bayer Advanced 24 Hour Grub Killer Plus
Sarah Browning: Make your garden nicer at night
Mow the turf before treating to shorten the turf height and make coverage easier. Mowing also removes weed flower heads that may attract pollinators, which would be killed by an insecticide application. Spray early or late in the day when insects are most active. On thick, well-established turf use a minimum of 1 gallon of water per 1,000 square feet to be sprayed. Follow product label direction on chemical use rates.
