Control grubs in the garden biologically

Cockchafer beetles are the larvae of leaf horn beetles. The most important species of leaf horn beetles are the cockchafer, but also the June beetle, welsh chafer and the garden chafer. The adult beetles damage the plants by feeding on the leaves. More serious, however, is usually the root feeding by the grubs. However, not all grubs are plant pests. For example, the larvae of the rhinoceros beetle, which are more commonly found in compost piles, feed exclusively on dead organic matter and thus help to convert garden waste.
Damage caused by grubs

Because white grubs live in the soil, preferably under sod, they do the most damage there. The grubs feed on the roots and thus interrupt the water supply of the grass. The formerly green lawn turns an unsightly brown and can be easily pulled off the ground. Underneath, countless white grubs emerge. Pecking and burrowing by birds and other animals destroys the turf nest by nest. Mainly affected are home, golf and sports turf.

Control white grubs with nematodes

Nematodes are natural enemies of white grubs. The nematode species Heterorhabditis bacteriophora and Heterorhabditis downsei, among others, are specialized on white grubs and can use them for their own feeding and reproduction. Before application, however, it is essential to determine which type of grubs are involved, as there are major differences in the type and timing of control.


Recognize grubs correctly

Leaf horn beetle grubs are very similar, but can be distinguished with a close look based on certain characteristics. In the following section we have prepared some characteristics and tips for recognition. If you are unsure, please use our free and non-binding identification service.



Analspalte eines Maikäfer-Engerlings

Cockchafer grubs

May beetle grubs have a whitish body and three pairs of legs and with brown head capsule. They can reach a length of 5-7 cm, which makes them much larger than grubs of other beetle species. A distinctive feature by which to distinguish cockchafer beetles is the shape of the anal fissure. The two vertical rows of bristles are characteristic for the cockchafer.

More information about the control of cockchafer grubs.



Garden chafer grubs

Garden leaf beetle grubs grow up to 2 inches in size, are white in color, and have a brown head. They often lie in a characteristic "C" position in the soil and remain there for about a year. They also have 3 pairs of legs and vertically extending rows of bristles, but these are less distinct than in the cockchafer grub. However, the decisive feature of the anal fissure is its pointed shape, as well as the curved fold at the rear end of the cockchafer, which resembles a grinning face.

More info on the control of garden chafer grubs.


June beetle grubs

June beetle grubs remain in the soil for 3 years, passing through 3 different larval stages. They move forward in a prone position, are creamy white with a brown head capsule and have 3 pairs of legs. The size depends on the larval stage of the grub.

1st larval stage approx. 1 cm

2nd larval stage about 2-3 cm

3rd larval stage up to 5 cm

Only the 1st larval stage can be successfully controlled with nematodes. The anal fissure resembling a Mercedes star is characteristic of June beetle grubs.

More information on the control of June beetle grubs.



Welsh chafer grubs

The larvae of the welsh chafer are creamy white with a brown head capsule. They grow to about 2 cm long and bear bristles on their backs and at the end of their abdomens. They also remain in the soil for several years before developing into fart beetles. The 2nd and 3rd larval stages can be controlled here.

More information on the control of welsh chafer grubs.

Identification service

You are not sure what kind of grub it is? Then use our identification service. Free of charge and without obligation.

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