Chafer Grubs cause similar damage to Leather Jackets and other root eating grubs such as the Vine Weevil.
Chafer’s are creamy coloured with a light brown head and 3 pairs of distinctive legs approx.10- 15mm long when fully grown. The chafer grubs are the larvae of Chafer Beetles. They hatch in the summer before turning into adults in late spring and have a lifecycle between 1 -3 years depending on the species.
In the summer the female beetle burrows into bare ground laying eggs close up to plants. A few weeks later the larvae hatch out, during this stage some damage is done as the grubs eat away at the roots of the plant.
Chafer attacks don’t follow any patterns, they can be a problem one year and not the next. They may appear in your garden but not in a neighbouring garden. Generally newly cultivated ground or neglected weedy gardens are more prone to chafer attacks.
A lawn in good health will survive minor infestations. If you get a heavy infestation serious damage can be done. First you will see small bald patches in the lawn and if you peel the grass back it will easily lift away. This damage is unsightly and can effect large areas of the lawn. Further damage can also be caused by animals and birds as they dig up the lawn looking for the bugs. When this happens the damage to the lawn can be extensive.
There are no legal chemicals available on the market to treat chafer infestations. You can buy nematodes which are natural parasites they latch onto the grubs and kill them. This method is expensive and nematodes are living organisms so they need to be used within a few weeks of purchase, or they too will die.
Prevention is cheaper and more effective than cure. Regular lawn care treatments will help and strengthening grass with an iron sulphate is cost effective as a healthy lawn will reduce your chances of getting an infestation in the first place.