Striped crane fly

Systematic position: The striped crane fly (Tipula scripta) is a member of the order Diptera, family Tipulidae. It is a well-known agricultural pest where the larval stage, often referred to as leatherjackets, lives in the soil and feeds on the root systems of various plants.

Affected crops and damage: Tipula scripta is a polyphagous pest, meaning it attacks a wide range of host plants. The larvae primarily target cereal crops, vegetable crops, turfgrass, and ornamental plants. By feeding on roots, stems, and underground plant parts, they cause significant physiological stress, often leading to stunted growth or total plant loss.

Biology and life cycle: The insect undergoes complete metamorphosis. Adult crane flies resemble large, spindly mosquitoes but do not feed on crops or humans. Females lay eggs in moist, rich soil. The larvae, which are legless and grey-brown in color, thrive in damp environments where they grow and develop by consuming decaying organic matter or living plant tissues.

Host damage characteristics: Damage is most severe in early spring when larvae are active after winter. Infested fields often exhibit irregular patches of yellowing or dying plants. Because the larvae remain underground, the damage is often discovered only when the plants begin to fail or the soil surface becomes infested with visible larvae following heavy rains.

Protection measures: Controlling Tipula scripta requires a combination of cultural and chemical strategies:

• Improving field drainage to reduce the moist environment favored by larvae.
• Cultivating the soil (plowing) to expose larvae to birds and drying weather.
• Applying insecticidal seed treatments to protect young seedlings.
• Using appropriate monitoring traps to assess population levels before making treatment decisions.