Chafer Grubs in the lawn

Chafer Grubs are the larvae of the Chafer Beetle, which is also known as the May bug. It can often be seen during warm evenings in the early summer. Chafer grubs have many similarities to Leatherjackets, they feed on the grass roots, the damage caused it similar and they attract the same predators.

Although not as common Leatherjackets, Chafer grubs can live in the soil for up to 3 years before they emerge on the surface as beetles. Chafer Grubs can measure up to 15mm in length. The head is light brown and the 'C shaped' body is a creamy - white colour with 3 pairs of legs on the upper body.


The adult beetles can measure up to 40mm in length. They have a black thorax with brown legs and wings.
The cycle begins in the adult beetle lays its eggs during the early summer, often in May or June (depending on the climatic conditions. Shortly afterwards the eggs will hatch and the grubs will feed on the grass roots until September - October. Following this period of activity they move deeper into the ground for the remaining winter months. Come spring time they emerge on the surface of the lawn as beetles.

The damage caused by Chafer grubs is very similar to that caused by Leatherjackets. The grubs feed on the roots of the grass causing a yellowing effect on the lawn as the grass weakens. The grass can easily be pulled out by hand due to the damage to the roots. The grubs will reach maturity during August - September, this is when the most extensive damage to the lawn will occur.

As with Leatherjackets predators such as birds and mammals will cause further damage as they tear up the turf as they go in search of these grubs. These predators include badgers, foxes and birds including crows and magpies.

Prevention and cure of Chafer Grubs

Identifying Chafer Grubs problems early is important so be vigilant and look for any abnormal bird activity on the lawn. Once the problem has been identified the lawn can be treated with a nematode based product available from most good garden centers.