Leatherjacket

DESCRIPTION

Species
The European crane fly, Tipula paludosa (Meigen), is a perennial pest in the Pacific Northwest, but other species of native crane flies may be associated with turf damage across North America. [Phylum Arthropoda: Class Insecta: Order Diptera: Family Tipulidae]

Hosts
The European crane fly is a significant turf and pasture grass pest and it is known to damage clovers, garden vegetables, and young ornamentals. This species feeds on the leaves of plants. Most native species, when found associated with turf, are found after the turf has been damaged by disease or grub activity. They are most likely feeding on the decaying organic debris.

Distribution
European crane flys occur in British Columbia, Nova Scotia, Washington, and possibly Oregon. It is a native of England and northern European countries. Other species of crane fly larvae may be found in turfgrass across North America and most are considered nuisances more than pests.


DAMAGES
Damage Symptoms
Larval feeding produces bare areas, sparse growth, and lodging of seed stalks. Activity usually occurs in irrigated turf or sites that tend to be moist. Damage can appear in small patches to areas that are several hundred square feet. European crane fly larval damage on golf greens can resemble that done by cutworms with sunken trails in the turf.

THRESHOLD

Monitoring
Information not available.

Threshold
Information not available.


CONTROLS

Cultural Controls
Habitiat Modification: The European crane fly is the only species that regularly can cause problems in turf. Other species are usually associated with turf that has been damaged from disease, overly wet conditions, or persistent snow cover. By dealing with these cultural problems, the crane fly problems tend to disappear.

European crane fly eggs and first instar larvae are very susceptible to desiccation. Refrain from watering turf in September. Ryegrasses, especially ones with endophytes, seem to be less preferred as hosts. In other sections of the country, try to reduce thatch layers and conditions that may saturate these during the fall months when adult crane flies are laying eggs.

Biological Controls - Parasitic Nematodes
The commercially available nematode, Steinernema carpocapsae, has been effective when used at label rates (1 to 2 billion infective larvae per acre). Other species, especially S. feltae, have also been effective.

Chemical Controls - Insecticides
Good control has been obtained by applying a surface insecticide that is registered for crane fly larvae between April 1 to April 15. Do not irrigate, or irrigate only lightly after the application since the larvae will ingest or contact the larvae on leaves as they emerge at night to feed. Larvae exposed to insecticides often surface for several days.


STAGES

Description of Stages
These flies have complete life cycles with eggs, larval (maggots or leather jackets), pupal, and winged adult stages.

Eggs
The black, 3/32 inch (1 mm) long, elongate-oval eggs have one side flattened and the other pointed. They are laid in clusters in turf.

Larvae
The eggs hatch into maggots which are white and worm-like. As these larvae grow, they molt into gray to grayish-brown larvae which develop a tough skin from which they have acquired their common name, leatherjacket. The larvae have four instars and at maturity they may exceed one inch (25 mm) in length. The head capsule may be exposed during feeding or moving but is often withdrawn if disturbed. The larvae have two typical spiracular plates (breathing holes) at the end of the anal segment. These plates are surrounded by six fleshy anal lobes.

Pupae
The translucent, brownish pupae have the legs, wind pads, and antennae glued down and are first present just below the soil surface. These one-inch (25 mm) long pupae wiggle to the surface at emergence time.

Adults
The European crane flies have a 3/4 inch (20 mm) long, slender body with very long legs, almost three inches (8 cm) from the front to back leg. Adults are brownish-tan with smokey-brown wings. Similar native crane flies can be larger or smaller, but they all have long legs and resemble giant mosquitoes. The adults generally do not feed.


LIFE CYCLE

Life Cycle and Habits
The European crane fly seems to require mild winter temperatures, cool summers, and an average annual rainfall of at least 24 inches. Adult flies, which look like giant mosquitoes, emerge from lawns, pastures, and roadsides from late August to mid-September. The adults may gather in large numbers on the sides of homes and other buildings. These adults can not bite or sting. The adults mate and females begin to lay eggs within 24 hours after emerging. The eggs swell in a few days by absorbing soil moisture. In about two weeks the eggs hatch into small, brownish maggots which begin feeding by using their rasping mouthparts on plant roots, rhizomes and foliage. By winter, the larva has molted twice and reached the third instar. This instar feeds slowly during the winter, but the fourth instar is reached in April and May. Turf damage is most evident in March, April, and May. The leatherjackets stay underground during the day but come to the surface to feed on damp, warm nights.

Feeding damage usually stops by late May into June. The larvae then rest in the upper soil and molt into the pupal stage in late July into mid-August. The pupae remain just below the soil surface for 11-12 days in August. When ready to emerge, the pupae wriggle to the surface of the turf, from late August through September.