The Crane Fly is a lawn-damaging insect that can attack all types of cool-season grasses found in the American Northwest, the Northeast and also parts of Michigan. Generally, it's only considered a lawn pest in the Northwest and as a nuisance in the other parts of the country.
The adult Crane Fly looks like a giant mosquito. This lawn pest has a brownish-tan, slender body, very long legs and one pair of long, smoky-brown wings. Crane Fly larvae are small and wormlike, ranging in color from olive-gray to greenish-brown. The tail end of their abdomen bears six fleshy, finger-like lobes. These lawn insects also have black-pointed heads that withdraw into the front parts of the body when disturbed. Most of the lawn damage caused by Crane Fly larvae and adults occurs in the spring, when larvae are feeding on grass roots, rhizomes, crowns and leaf blades. The result of these feeding habits are areas of sparse grass, missing foliage and bare grounds in both lawns and landscaping. Closer inspection of these areas may reveal large numbers of larvae in the thatch and upper soil, whereas large numbers of adults can be seen congregating on walls of buildings.
Crane Flies produce only one generation per year. This lawn-damaging insect lays its eggs just under the soil surface because they require adequate moisture to survive. Crane Flies overwinter as larvae, but this only slows down its life cycle during cooler periods.
There are two methods for controlling Crane Flies that TruGreen® recommends: 1. Use professionally applied pest control designed to prevent excess lawn pest populations, which can cause damage to your lawn 2. Kill insects, grubs and other lawn pests before they have a chance to damage your lawn Proper mowing and watering techniques can also help foster a healthy lawn that's more tolerant to lawn pest attacks—plus you'll get a lawn you'll want to live on in the process.