Leather jackets feed on grass roots from September through to the following summer. They are legless, greyish brown larvae of the cranefly (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 be pulled up by birds feeding on the larvae. Control them with Leatherjacket nematodes (Steinernema feltiae)! These microscopic transparent worms feed and multiply inside the larvae causing death. Simply dilute the nematodes with water before use. Use treatments before September and October for effective control or when pest is present. A second treatment may be applied the following spring, typically between April & May (at double strngth). Apply to moist compost/soil when the soil temperature is above 12 degrees using a watering can or nematode applicator. Treats up to 10m2.
