What are leatherjackets?

Leatherjackets are the larvae of the crane fly. Or, as we better know them: daddy long legs. During the autumn months one female crane fly can lay up to 300 eggs in your lawn. Once hatched, the larvae wreak havoc in two ways: firstly, by feeding on grass roots which results in dead patches of lawn; and secondly, by causing their natural predators such as foxes, badgers, birds, and moles to dig up your lawn looking for food.

How do I spot leatherjackets?

The first obvious symptom of leatherjackets is yellow and brown patches of dead grass, but this is also a symptom of many other lawn issues. By digging into a small section of turf you will be able to see the leatherjackets in the affected layers of the soil. 

You will also spot leatherjackets on the surface of your lawn during heavy rainfall, as the water forces them above ground.

How can I treat leatherjacket infection?

Our environmentally friendly, biological insecticide treatment uses nematodes to seek out and kill the larvae. Once present in your lawn, nematodes will penetrate and kill leatherjacket larvae in order to reduce the population and to help prevent further damage in the future.

This ingenious treatment needs to be applied in the right conditions – when the soil temperature is above 12 degrees – so optimum application time is usually between July and October.

The soil needs to stay moist for the nematodes to survive once applied, so you will need to frequently water the lawn if there hasn’t been much rain running up to their application. Also, in preparation, the lawn should be mowed and spiked to ensure that the nematodes have maximum opportunity to reach the pests inhabiting the top layer of soil. We mix nematodes with water and apply it using a backpack sprayer.