- Pest Type: Insect
- Crops Affected: Potatoes
- Scientific Name: Tipula dorsimacula
- Pest Order: Diptera
Leatherjacket adults, or craneflies, are about 15-25 mm long with very long and fragile legs. They resemble mosquitoes, but are much larger, and do not sting or bite. Eggs are oval, black, shiny, and are about 1 mm long and 0.5 mm wide. The larvae are called leatherjackets because of their thick skin which resembles leather in appearance. Their color ranges from gray to greenish brown with black specks. They have instars, generally four, which are all similar in appearance. Leatherjacket larvae are wormlike, taper at both ends, have no legs, and grow to be 3-4 cm long.
Larvae feed underground on tubers, causing punctures varying from shallow depressions to deep holes. Various species of cranefly are more commonly found in turf, but feed on the underground portion of various crops, including potatoes.
The leatherjacket larvae commonly emerge from late July through September, just when potato tubers are available. They generally overwinter as larvae. In the spring, they resume feeding on roots of whatever plants are available, often on in turf grasses. They pupate in early to mid-summer. Adults emerge in summer, fly around, and lay eggs. One female cranefly can lay from 200 to 300 eggs. The eggs hatch in 1-15 days, and the larvae start to feed immediately and continue to feed throughout late summer and fall.
Control of this pest can be difficult. Contact local advisers regarding economic thresholds and the best control measures in your area.