Treat Chafer Grubs when you first see grubs, up to mid Sept when the grubs are close to the surface and active with an insecticide only available to the professional or August, September and October, to target the adult beetle recommend Nemasys Chafer Grub Killer.
Spotting adults chafer beetles will help you to identify the pest responsible for the damage, BUT always inspect the lawn for the grubs to be sure. Chafer Grubs are creamy coloured, approx 1.5 cm in length and have distinctive legs. They are found in grass roots. Like leatherjackets, chafer grubs attack the grass roots causing identical symptoms, but chafers are larger and creamy coloured, making them easy to identify.
The Garden Chafer Beetle emerges in May/June from the lawn and mate before laying eggs. These eggs hatch to produced chafer grubs. The eggs are often laid in the same place each year so the problem gets progressively worse. The Chafer Grubs feed on grass roots from July until late Autumn before burrowing deep into the ground to pupate. They are a source of food for crows and woodpeckers as well as foxes and badgers. These may do more harm to your lawn. The Chafer Grubs lay dormant during the winter before moving to the surface in the spring to emerge as beetles in May / June. Treat these newly hatched when they are near the surface in August.
In Autumn Nemasys® Chafer Grub Killer contains Heterorhabditis megidis nematodes which kill Chafers but is harmless to children, wildlife and pets and the lawn may be used immediately after application. Apply by watering can or hose end feeder.
For more information and to buy the product: www.nematodesdirect.co.uk/11-chafer-grub-killer-nematodes
What you will need to do to prepare the ground?
Whatever product you choose watering is key, the lawn should be watered about 3 days prior to treatment and thoroughly watered after application for beneficial effect.
Important Notice: The professional insecticide is being withdrawn from use in June 2015 and we can only apply while stocks last until June 2016, after which nematodes are the only control available. These will need to be applied in the Sept and October period