CRANE FLY LARVAE IN LAWNS
Stephen Bambara, Extension Entomologist
CAUTION: These recommendations
were developed for North Carolina and may not apply to other areas.
CRANE FLY, Tipula sp., Tipulidae,
DIPTERA
General Information
Adult
crane flies, Tipula sp., resemble giant mosquitos. The wing span may
be two inches across. Adults are clumsy and weak fliers. They are often found
resting on an outside wall of a house, under a porch or in a garage. They may
gain entry to a house when a door or window is opened. However, crane flies
are harmless to humans. They cannot bite and have never been implicated with
any disease. Adults are short lived and may feed on floral nectar or not at
all. There are many species. Some new invasive species (Tipula oleracea L. and T. paludosa Meigen) are beginning to cause damage or problems in turf in New York.
Biology
The larvae
(maggots) of crane flies are sometimes called leatherjackets because of their
tough skin. They are commonly two to three inches long and have no legs. Leatherjackets
sometimes infest tobacco plant beds where they apparently feed on the roots
of the tobacco seedlings and are of some economic concern. Some species are
reported occasional pests of turf or pasture and forestry
seedling beds, mostly in the North Western United States. Some species of
crane flies have predaceous maggots (feeding on other invertebrates) and some
feed on decaying organic matter. They may be more noticeable above ground at
night. Some species have aquatic larvae. Around homes, larvae may be developing
in wet turf, nearby streams or in the surrounding damp woodlands. Adults are
very short-lived, but there could be extended adult emergence periods during
a season making it appear that the adults live more than a few days. Populations
decline when soils dry.
Control
Control measures are rarely required in NC and could introduce chemicals unnecessarily
to the environment and waste money. To monitor populations in turf, cut three
sides of a 6" x 6" square of turf with a knife. Pull back the flap
and examine the root zone. Soapy water flushes may be a good diagnostic tool for determining maggot populations. If the sample of the turf reaches 25 larvae, they
may be numerous enough to do damage to weak turf. Healthy turf may sustain 40
or more larvae per sample. Suggestions include keeping turf strong and healthy
without overfertilization. Try to eliminate situations where lawns stay overly
wet for long periods by improving drainage. Temporary relief might be achieved
by raking larvae up at night and drowning them in a bucket of soapy water or
take the day off and use them to go fishing. Application of turf insecticides often cause cause maggots to come to surface to die. Acelepryn is one such product labeled for European crane fly larvae with application in fall.
Fishermen may enjoy tying flies
of the adults, though I suspect the larvae to be better bait.
Photo Credit- Adult, Drees, Texas AMU. Larva, unknown
Other interesting links-
Other Resources
For assistance with a specific problem, contact your local North Carolina
Cooperative Extension Service.
Prepared by: S. Bambara, Extension Entomologist
Published by North Carolina Cooperative Extension Service
Distributed in furtherance of the Acts of Congress of May
8 and June 30, 1914. Employment and program opportunities are offered to
all people regardless of race, color, national origin, sex, age, or disability.
North Carolina State University at Raleigh, North Carolina A&T State
University, U.S. Department of Agriculture, and local governments cooperating.
© 2003 NC Cooperative Extension Service
ENT/ort-129 April, 2003
Web page last reviewed January, 2011 by the webperson.