Things You Should Know About Turfgrass Grubs

Grub Damage

Is your turfgrass wilting or yellowing despite your dedicated watering and fertilization? Such wilting and yellowing can be early signs of grub damage.

Here are things you should know about white grubs and how to deal with them.

What are Grubs?

White grubs are a common turfgrass insect pest. They are the immature (larval) stage of scarab beetles. The grubs are small, C-shaped and have a dark head capsule and three obvious pairs of thoracic legs.

White Grubs Found in Utah

The established white grub species include May/June beetles, black turfgrass Ataenius, and masked chafers. You may also find the Japanese beetles in some lawns. Since your lawn expert in Utah will deal with all white grubs in a similar way, species identification is usually unnecessary.

Grub Damage

White grubs love to feed on turfgrass roots. As grub feeding continues, the grass starts wilting or yellowing. It becomes loosely attached to the soil and may feel spongy and pull up easily. Dying turf then develops into brown patches of lawn.

Cultural Control of White Grubs

The following biological control methods can help you reduce grub damage:

  • Plant flowers that attract birds, wasps, flies, and other natural enemies of grubs
  • Do not exceed recommended grass irrigation and fertilization schedules. Overly maintained lawns could be attractive places to lay eggs for beetles
  • Monitor for white grubs in the early spring and scout for beetles in the summer
  • If you find adult beetles, remove them by hand and drop them into a jar of soapy water

Chemical Control of Grubs

If you detect grub-damage, you may need to control the pest with insecticides. Apply a long-lasting “reduced risk” pesticide before the beetles’ eggs hatch. Consult a professional lawn service if your turfgrass is highly infested.

White grubs are the most prevalent and destructive turfgrass insect pest. Fortunately, good cultural practices can help you control these lawns and garden pests. An experienced Utah lawn expert can help you keep your grass healthy and pest free in a sustainable way.