Chafer Bugs - A threat to your lawns and beds

Chafer Bug larvae can cause devastating damage to lawns. Some of the damage is caused by the grubs chewing at the roots of the grass, but much of it is caused by birds and animals scratching away at the soil searching for the juicy grubs.

Identifying the larvae Common Chafer Grubs are white grubs with a brown head, not unlike Vine Weevil grubs but with distinct pairs of legs at the front end.
Note that common chafer grubs only reach 20mm in length. They are about the thickness of a matchstick. If you see something twice this length it is probably a cock chafer. Cock chafer are not susceptible to nematode treatment being tougher, and having a longer life cycle. However it is the common chafer which is the one commonly found in lawns.

May Bugs Chafer Grub larvae hatch out to become flying beetles - sometimes called May Bugs because they typically emerge in mid May. Chafer Grub adults lay eggs in June which turn into more Chafer Grubs in July to eat grass roots until October. Then Chafer Grubs dig deeper into the soil over winter until May before Chafer Grub surface to fly, mate and lay eggs again.

Biological control with nematodes

Heterorhabditis megidis

We supply  microscopic beneficial nematodes (eel worms) which are watered into the lawn. They enter the chafer bugs and poison them so that they will die within a few days. more about nematodes

The nematodes arrive in a paste or gell. Mix them vigorously with water and sprinkle on the lawn following the instructions on the pack. Apply when soil temperatures are above 10°C. The best time to use the chafer bug control is August and September when freshly hatched grubs are present in the top few centimetres of the turf.

The grass should be moist before the application and should be irrigated directly afterwards to wash the nematodes into the soil. It should be kept from drying out over the next 2 or 3 weeks, or the nematodes will dry out too. They do not harm any humans, birds or animals.