From early August through until the end of October our garden lawns will be subjected to attacks by birds, foxes and badgers on the search for the grubs of the Chafer and Leatherjacket.
Both underground grubs cause lawn damage by chewing away at the roots of the grass but the real risk is birds and animals on the search for these tasty morsels. Jays, magpies, crows and rooks, plus badgers and foxes, are the chief culprits and can effectively rotovate large areas of lawn.
Chafer Grub and Leatherjacket larvae typically hatch from late July and stay underground until they pupate the following April/May. They remain reasonably close to the lawn surface until the colder weather, when they burrow down deeper for protection from the cold and the birds and animals.
Chafer Grubs that survive emerge as May Bugs and Leatherjackets as crane flies (Daddy Long Legs). Both lay their eggs on the lawn surface in the summer and the cycle repeats itself. Chafer Grubs are white with orange/brown heads and have a clear pair of legs at their front end. The Leatherjacket larvae is a grey/brown colour and usually about 2.5cm long.
The most effective treatments are Nemasys Biological chafer grub killer and Nemasys Biological leatherjacket killer from BASF Lawn and Garden. Both use nematodes to attack and kill the larvae and are compatible with organic gardening. These naturally occurring microscopic animals are specially bred for pest control as BASF’s state-of-the-art facility at Littlehampton in Sussex. They enter the larvae through natural openings and, once inside, kill them.
Both products are applied by mixing with water either using a watering can or a hose feed. To ensure the lawn stays free of marauding corvids, foxes and badgers the Nemasys treatment should begin in early August and for more effective control, two treatments two to four weeks apart should be applied. It is important to water the treated area thoroughly immediately after each application and keep the area moist for at least two weeks. BASF recommends that the grass is cut before each treatment.