School IPM Best Practices

European Crane Fly, Tipula oleracea and Tipula paludosa

European crane fly larvae

D. Peck.

IPM Steps to Reduce European Crane Flies

1. Sample for Pest

Confirm the presence of European crane flies before you treat.

Where to find it while inspecting: You will see most adult crane fly activity near turf, water sources or lights near buildings. During the European crane fly’s two mating seasons you will see them on top of turf. Larvae can be found in turf, under thatch, two times during the year. Occasionally the presence of the pupal case, called “Leather Jackets” show ECF activity. Damage to turf will show up in May as browning turf and bare spots. ECF is not a widespread pest throughout the Northeast but is expanding.

2. Proper ID

Are they European crane flies?

Size and Appearance: Adult flies are large, with clear wings, long body and long delicate legs and resemble “giant mosquitoes”. Larvae are dark gray to brown and legless.

3. Learn the Pest Biology

European crane fly pupa

T. Cook.

What is the life cycle of European crane flies?

Life Cycle: Adults emerge from grasses in late summer and fall, and mate within 24 hours. Eggs hatch within days and larvae feed on turfgrass roots and crowns during the fall. T. paludosa overwinter in the soil and come up to feed again in spring. By mid-May they begin to pupate until adult emergence. T. oleracea have two generations, so adults are seen in the spring as well.

Preferred food sources: Roots, emerging stems and leaves of grass plants.

Preferred habitat: Low mown turfgrass lawns as well as unmown field grasses. Note: Native crane flies (often found near creek) do not cause the damage to turfgrass that the invasive species do. It is not easy to tell the difference, so ask your county cooperative extension agent if European crane fly has been detected in your area and if so, it may be responsible for turf damage as well. Telltale sign of ECF activity is a large number of adults moving above the turf in May and September. Native crane flies do not gather in large groups on turf.

4. Determine Threshold

How many European crane flies are too many?

Threshold: Sample soil in March by using a cup cutter or sharp spade and dig up a 6x6" area. Larvae will be in the turf “crown” layer or thatch. Healthy turf may tolerate 40 larvae per square foot, but as few as 15 will damage stressed turf. Larvae may be present in heavy numbers in one area and nothing found 15 ft away, so sample in multiple areas to determine populations. NOTE: If a 4-inch diameter cup cutter is used, multiply the number of larvae in each core by 11.5 to get the number of larvae per square foot. If a 6x6" area is sampled, multiply the number of larvae by 4 to get the number of larvae per square foot. Sample three or four locations and determine the average number of larvae/sq. ft.

5. Choose Tactics

European crane fly adult

T. Cook.

Creating a healthy soil condition and understanding turfgrass’s needs is the first step in reducing turf pests. What can I do to treat, reduce, or prevent European crane flies?

Best Management Practices: Population is supported by areas that tend to moisture in spring and fall. Well drained soil helps. In some cases, dry weather will cut back on their populations, therefore you may want to refrain from irrigating turfgrass during the egg-laying period (high activity of adults on top of turf). Maintaining healthy turf will reduce damage: Maintain proper soil pH: 6.0 to 6.8 (test every 3–5 years). Fertilize at the proper time for turfgrass root development, primarily fall (late spring at times when turf is weak and thin), irrigate if needed unless it will reduce egg and early larval survival, mow at proper height (removing no more than 1/2 of the blade, amend poor soil, choose proper turfgrass seed for your conditions, buy quality seed, overseed thin spots in fall or early spring, remove thatch.

Treatment Methods: In heavily infested patches, localized applications of insecticides may be appropriate if timed correctly and allowed under district and local restrictions

6. Evaluate

Was the tactic successful? Record the date pests were first noted, and the tactic you used, and its success. Use one of our RECORD KEEPING tools.

For More Information:

NYS Integrated Pest Management Program Fact Sheets: European Crane Fly


When a pesticide application is necessary, all necessary and required precautions are taken to minimize risk to people and the environment and to minimize risk of pesticide resistance or pest resurgence. Pesticide use in your school may be prohibited or regulated by local policies or state and federal regulations. Risk reduction methods can include, but are not limited to, spot-treatment, the use of gel or paste bait formulations placed in inaccessible locations, injection into a crack or crevice, and other methods that reduce potential exposure.