Leatherjackets

In the last couple of years leatherjackets have proved to be a huge problem in the gardens of Donegal. While spotting an infestation of leatherjackets is notoriously difficult, spring is a good time to try and identify and treat these pests before the problem gets out of hand.
   Leatherjackets are a real nuisance in the garden. They are the immature larvae of the common Daddy Longlegs. They take the form of two inch long, grey, legless grubs which have particularly tough skin. While leatherjackets can be active at any time during the growing season, they tend to do most damage in early spring. These grubs favor reasonably loose soil and are commonly found in gardens which have been cultivated in the last few years. They live underground where they eat the roots of plants, leaving yellow or brown patches of dead grass on lawns. In particularly bad cases whole lawns have been killed off by an infestation.
   Spotting leatherjackets in a lawn can prove tricky. By their nature these grubs feed from below the ground, so the damage to plants and grass can be done before the problem is spotted. Wet weather however usually gives these pests away. Following a heavy nights rain leatherjackets can be found gathering on the surface of the lawn or on the nearby driveway.
   When an infestation of leatherjackets is discovered there are a number of ways of solving the problem. The most common and effective way of dealing with an infestation is to treat the area with a suitable soil insecticide. These insecticides are available from most garden centres and should be applied according to the manufacturer’s instructions in early spring when the grubs are most active.
   However if you don’t like using chemicals an alternative is available. An old gardener’s trick is to water the effected area thoroughly in the evening and covered with black plastic sheeting. In the morning the grubs will have been drawn to the surface where they can be physically removed and disposed of or left for the birds to eat.
© Copyright, Highland Landscapes, Letterkenny, 2008.