Leatherjackets are one of the worst insect pests to cause problems in lawns, particularly at this time of year. Poorly drained lawns are worst affected. Crane flies, which are more commonly known as the “Daddy Long-Legs” lay their eggs in your lawn in late summer. Grubs hatch around this time of year. Come the spring, the grubs feed on the roots and stems of the grass plants, meaning patches of your lawn, potentially will begin to turn brown and yellow.
A well known tip to check for leatherjackets in the spring, is to water the suspect area, cover with plastic sheeting, and leave overnight. The next morning, the grubs will be on the surface, around 2.5cm, with no legs. Another sign of activity, is birds pecking at the lawn.
Controlling the problem
The best cure is prevention – aerating your lawn will help improve drainage. This will help prevent the Crane Fly from laying its eggs in your lawn. If you have an area of lawn that is badly affected, you can use a water soluble pesticide that contains imidacloprid.