When you see them, you think you're on the set of a B-movie - something like The Attack of the Giant Mosquitoes. After all, that's what European crane flies look like. The adults are harmless. It's the larvae that do all the damage. Sometimes called leatherjackets, these larvae hatch in the fall and live on grass blades until they go underground for the winter. In the spring, they're back out on the lawn. They're very tough on that new grass you just planted.
Your lawn gives them away. In the fall and spring, look for patches of damaged grass. These patches may grow together and spread. Where the infestation is heavy, you may see a brownish paste. Dig into your soil and look for brownish-grey larvae about 1 inch long. A few are no problem. If you see lots - say, 80 per square foot - you should control them.
The adults are a feast for birds. Sparrows and robins just love them and can do a lot to control future populations.
You want to control European Crane Fly larvae when they're most active - usually in early to mid-April. Ask the people at your lawn and garden center for control products for this pest. As always, be sure to follow the instructions on the label.
The European crane fly is an invasive species that is becoming prevalent in the northwest. While native species of crane flies live on decaying leaves, this new variety attacks pastures and lawns. The adults are harmless, but the larvae can damage your lawn
