DESCRIPTION
Adults are large (2 cm. long) mosquito-like flies, appearing in August and September. Larvae are grey legless worms varying from 3 mm to 2.5 cm long, spending most of their life in the top 2.5 cm of the soil.

DAMAGE
Larvae feed on roots of grasses and legumes, causing plants to weaken or die. When sufficient larvae are present lawns develop irregular-shaped yellow patches.

LIFE CYCLE
Leatherjackets overwinter as young larvae. As soil temperatures increase in March through May, larvae feeding accelerates (as does damage). Larvae reach their full size by mid-June before pupating in July. Adults emerge in August, laying eggs through into September. Eggs hatch in about two weeks, with young larvae doing little damage before winter.

CONTROLS
• Ensure a healthy lawn through proper care. To monitor leatherjacket populations, remove a 15 cm by 15 cm piece of sod 5 cm deep in early May.
• Submerge in a salt solution for five minutes. If more than five
larvae surface, a pesticide should be applied before May 31.
• Control is not necessary in fall as many larvae usually die over
winter.
• Keep a pest journal for next year, including location and severity of damage, controls used and when damage was first noticed.

PESTICIDES

• Chemical-Diazinon soil drench at label rates once between October and May when the ground is not frozen.
• Alternative-none recommended. (to print, right-click on this page)