What Is a Grub Worm?

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Grub worms, also called lawn grubs, are white worm-like pests that live in the soil. They are the larval form of the adult Japanese beetle, sometimes called the June beetle. Each larva is about ½ inch long with a small brown head.

Grub worms eat the roots of turf grass and ornamental plants. Grub worms turn lawns brown and attract predatory animals, such as skunks and raccoons, that further damage lawns. There are chemical and natural fertilizers that control grub worm populations. Nematodes are the natural enemies of grub worms, but they can only affect young larvae. Grubs are active from the early spring through the early fall.

The adults emerge beginning in spring and are attracted to light. The female grub worm will tunnel into the soil to deposit her eggs. Patches of brown on the lawn that you can peel away in sections, like carpet, are indicative of a grub worm infestation. There are several treatments for grub worms, including pesticides like Neem oil that can be sprayed on to the lawn to kill them.