Grubs in lawn

White grub life cycle

If you have problems with large larvae or grubs in the lawn, it is often a type of Lawn Grubs or the White Grub (the larvae of the June Beetle (Phyllophaga anxia), European Chafer (Amphimallon majalis) or Japanese Beetle (Popillia japonica)), which can cause great damage to the lawn.

Grub life cycle

Damaged parts occur in patches where the grass withers and dies. The affected spots become larger and larger and in many cases, the grass is completely loosened from the surface and can be lifted up. It is usually landscaped lawns on lighter soil that are affected.

The adult beetle is yellowish-brown, hairy and about 0.8 inches (2 cm) long. When swarming, which occurs during the summer months, the female beetles lay their eggs in the soil. They hatch and grow to 3-4 inches long yellowish-white larvae with brown head. These larvae feed on grass roots. In winter they creep down to the frost depth to spring back to search upwards to eat roots. In late spring they pupate and become a beetle that is ready to lay eggs.

How to get rid of the grubs in lawn

In the past there were not many ways to combat the larvae in addition to repeatedly mill lawn, and then re-sow the lawn. Today, there are biological pest control methods that works well. In particular, there are nematodes to buy that are applied by watering.

Nematode methods

Nematodes are a type of worm-like animals, mostly microscopic. They live in symbiosis with bacteria, and it is the bacteria that is the active pesticide. When the nematode enters its "host larva", it brings with it bacteria. Within a day or so, the bacteria have killed the larva. 

Carefully follow the advice of the manufacturer. It is important that the instructions are followed for the nematode method to work. Since the nematodes are live animals, the method requires soil moisture, heat, and thatthe  watering does not occur in the hot sun (nematodes are UV-sensitive).

Although chemical pesticides are available, they usually have less effect.

If the full-formed beetles are already there, one way to easily remove them is to, when the beetles are swarming, put out bright yellow buckets of water and some detergent in. The beetles are attracted to the yellow color, and drown in the water.

 

Using this method, you can get rid of your problems with grubs in lawn and enjoy a healthy lawn. 

 

Image: Wikipedia Commons