Insects

Crane Fly

(Leatherjackets)

Crane Fly
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Adult crane flies emerge from the soil beneath turfgrass, pastures and other grassy areas in late summer and fall. The adults have very long legs and resemble large mosquitoes.

Target: All turfgrass species appear to be susceptible, as well as vegetable and small fruit crops.

Damage: The larvae are the damaging stage of this pest. They feed on the roots, crowns, and above ground portions of grass plants. Damage often becomes noticeable in March and April and appears as dying patches of turfgrass. Weeds may invade areas of dying turfgrass. Although the adults resemble mosquitoes, they do not bite or sting; it is believed that they feed primarily on plant nectar.

Life cycle: Females mate and lay eggs in grass within 24 hours of emerging. Eggs hatch into small, brown, wormlike larvae that have very tough skin and are commonly referred to as “leatherjackets”. The leatherjackets feed on the roots and crowns of clover and grass plants during the fall. They spend the winter as larvae in the soil; when the weather warms in spring, they resume feeding. During the day larvae mostly stay underground, but on damp, warm nights they come to the surface to feed on the aboveground parts of many plants. When mature, the larvae are about 1 to 1½ inches long. Around mid-May, they enter a non-feeding pupal stage and remain just below the soil surface. In late summer, pupae wriggle to the surface and the adults emerge. There is one generation a year.

Notes: Healthy, well maintained turfgrass can tolerate fairly high larvae populations. Nitrogen fertilizer and irrigation may reduce damage.