The larvae of cockchafers are among the most harmful of the so-called grubs. They can cause significant damage to the lawn or ornamental and useful plants in the garden. However, there are definitely effective ways of recognizing them and limiting their harmful effects.

Cockchafer grubs look confusingly similar to June bug grubs

The harmful potential of cockchafer grubs

Of all the grub species that occur in our Central European latitudes, the cockchafer larvae are the most feared. During their three to four-year subterranean development phase, they eat their way through the tender roots of all sorts of ornamental and useful plants, thick and round. With increased occurrence, this can cause a certain amount of damage, especially in garden lawns and vegetable beds.

Compared to times before 1950, however, the May beetle accumulation is no longer really a threat. Because the animals regularly caused crop failures and tree bare trees, they were heavily fought and almost wiped out until the second half of the 20th century. Today, the extent of damage, especially in private gardens, is therefore rather moderate.

To remember:

  • Cockchafer larvae are among the most harmful grub species
  • May beetle numbers have declined sharply since the second half of the 20th century
  • Damage in private gardens is therefore moderate

How do you recognize cockchafer grubs?

Cockchafer grubs show a very typical grub appearance: With a length of 5-6 centimeters, they are medium-sized and therefore quite easy to find. Their thick, caterpillar-like segmented body is curved in a C-shape. When you pick it up, it contracts even more. The body color of cockchafer grubs is yellowish-cream white, the slightly thickened abdomen is dark and the head is brown. 3 long, bent pairs of legs attach to the chest and serve as digging tools for the grub.

damage and control

Typical indications of a cockchafer grub infestation are islands in the garden lawn that look dry and can be easily removed, and dying ornamental and vegetable plants in the bed. If you dig up the ground under a dead turf island, you can make out the gnawed roots and probably the grubs as well. As a first measure, such digging up and manual removal of the pests makes sense.

For targeted and complete control, it is advisable to place predatory nematodes on the larvae. You can order these online, for example. They parasitize the grubs and reliably kill them.

prevention

In order not to get into trouble with the voracious cockchafer grubs in the first place, preventive measures are also useful. Above all, thorough, regular soil care is the be-all and end-all here. In order to make it more difficult for adult cockchafers to lay their eggs in the lawn, you should mow and scarify it regularly. This strengthens the turf.

In beds, it helps to weed diligently and, if necessary, to stretch insect protection nets over them during the flight times of the adult beetles, i.e. in May and June. Of course, this only applies to the cockchafer years, which are repeated about every four years according to the larval development period.

In order to keep adult cockchafers away, you should also avoid night lighting in the garden. They attract the beetles, which orientate themselves towards the light, and encourage them to establish themselves and lay eggs.

Category:

Animals in the garden