Leatherjackets

Leatherjackets are the larvae of craneflies, which encompass around 350 species in Britain, spanning six true fly families: Tipulidae, Pediciidae, Limoniidae, Cylindrotomidae, Trichoceridae, and Ptychopteridae. While many of these species are rare and contribute to healthy ecosystems by feeding on decomposing organic matter or algae, a few feed on living plant material and can cause garden damage. Leatherjackets have elongated, tubular bodies up to 30mm long, are greyish-brown and lack legs or an obvious head. They cause lawns to develop yellowish-brown patches, often killing the grass, distinguishable by lifting the affected turf to find leatherjackets in the soil. Water soaking and covering the lawn with light-impervious material can reveal large numbers of grubs if leatherjackets are the issue. Birds like crows, magpies, rooks, and starlings searching for leatherjackets leave small round holes in the turf. In flower beds or vegetable plots, leatherjackets can kill seedlings and small plants by damaging stems at the soil level.

When you start to see daddy-longlegs in your garden, which is normally towards the end of August, you will know that in a few days they will be laying eggs in your lawn. This is when the young leatherjackets are active in the soil and are most susceptible to the treatment we provide.

If you have seen leatherjackets on your lawn at any other time of year, i.e. in the spring/summer, then we will need to treat twice. We recommend two treatments per year for leatherjacket infestations, in spring and autumn, as this will give you maximum protection.

We use a 100% biological control for managing leatherjackets in lawns. This treatment is watered into the turf or soil. The treatment enters the bodies of leatherjackets and infects them with a bacterial disease. For it to be effective, the soil needs to be well-drained but moist.

Make sure the lawn does not dry out after we apply the treatment and keep it well watered for at least two weeks. This is very important to ensure the biological control works effectively and the leatherjackets are eradicated from your lawn.