How to Prevent & Control Crane Flies

Also known as leather jackets, these hungry larvae can turn your lawn into a patchy, pasty mess.

Attack of the giant mosquitoes! Crane flies aren't mosquitoes, but that's what you might think when you see them buzzing around your property. The adults are harmless, but watch out for their larvae because they can wreak havoc on your grass.

Crane Flies: What You Need to Know

Crane flies are prevalent throughout the U.S. and most of the world. They are sometimes called mosquito hawks or mosquito eaters and mistakenly believed to feed on mosquitoes. Most adult crane flies do not feed, however crane fly larvae do feed on a variety of food that includes grass roots and decaying organic matter. While native species of crane flies live on decaying leaves, the European species attacks pastures and lawns.

Larvae of European crane flies are also known as leatherjackets. They hatch in the fall and live on grass blades until they go underground for the winter. In the spring, they'll come back out on the lawn. They're especially harmful to new grass.

Kill & Prevent Crane Flies and Larvae

Identify European Crane Fly Larvae in Your Lawn

Your lawn's appearance gives them away. In the fall and spring, look for patches of damaged grass. These patches may grow together and spread.

Dig into your soil and look for brownish-grey larvae about 1 inch long. A few are not an issue, but if you see many (about 25 or more per square foot), you should take measures to eliminate them.

Stopping the Larvae

You want to kill European crane fly larvae when they're most active – usually in early to mid-April. Apply Ortho® Bugclear™ Insect Killer for Lawns & Landscapes Ready-to-Spray around your property. It kills by contact to start creating a bug barrier in minutes. Be sure to follow all label instructions.

Let Nature Control the Adults

The adults are a feast for birds. Sparrows and robins love them and can do a lot to control future populations. Use Ortho® Bugclear™ Lawn Insect Killer1 on your lawn if the birds aren't snacking fast enough for you. You can also create a bug barrier around your home using Ortho® Home Defense® Insect Killer for Indoor & Perimeter2 to prevent adult crane flies from entering your home.