Leatherjacket’s feed on grass roots from September through to the following summer. They are legless, greyish brown larvae of the crane fly (daddy long legs). They pupate in the summer and adults typically emerge in August, sometimes in huge numbers, ready to lay eggs again. The larvae weaken the lawn which can then be pulled up by birds feeding on the larvae.
Use treatments between September and October for effective control or when pest is present. A second treatment may be applied the following spring, typically mid April – mid May (at double strength).