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Lawn Grubs Causing Brown Spots?

Lawn with brown patches

Do you have thin grass that turns yellow? Is the grass too soft and spongy? Can you pull it out easily without the roots clinging to the soil?

If you answered “yes” to one or more of these questions, it could be a sign of a grub worm problem. Here’s how to test for these lawn lawn grubspests:

  1. Cut a square-foot piece of sod on 3 sides, so you can lift it up like a flap (your cut should be about two inches down.)
  2. Lift the grass for a look at the bugs underneath.

Can you spot more than one or two “C”-shaped grubs? That is probably too many, and a signal for you to get help. But if you see one or two grubs, then stay calm. A healthy lawn grows continually, and the grubs can’t eat enough to damage it. It’s only when the number of grubs starts to get too high that you run into a problem.

How do grubs cause this damage? They like to eat at the roots and make tunnels through the root area. As the grass sustains this damage to the root, it becomes difficult to absorb the necessary water and nutrients for optimum health.

The other downside of having too many grubs in your lawn is that they attract other predators. Animals like raccoons and armadillos love to feast on grubs. If you notice wasps with light belly stripes frequenting your yard, be suspicious. These guys also like to attack lawn grubs.

If you don’t treat your grub infestation, the grass will start getting browner and the dead areas will get larger. The lawn will stop responding to watering and fertilization. In the worst-case scenario, you could be forced to re-sod.

Don’t hesitate to call a professional for help. They can use approved treatments to interrupt the life cycle of the grub worm and stop it from inflicting further damage.