As July fades into August, lawn grubs are hatching and beginning their fall feast on your tender grass roots. This fills their bellies and sustains them as they descend below the root line to overwinter. It also kills your grass, although it may not be apparent until next spring.
Checking for grubs is easy. Using a sharp knife, cut one-foot square sections of sod from various areas of your lawn. Pull the sod back. If you see white crescent-shaped creatures, those are grubs. Count them. If each square contains six or fewer, there’s no need to treat for them. They won’t do enough damage to kill the grass or even cause it to be unsightly. If you count seven or more per area, you should treat the whole lawn.
The presence of large, brown beetles over the last two months would mean there’s a good chance that you have grubs. These beetles, commonly called June bugs, that fly into your window panes are the adult stage of lawn grubs. They’re flying around looking for a mate.
After mating, the females lay eggs in the turf. Immediately upon hatching, the small grubs burrow into the soil, stopping for a meal of grass roots on their way to the warmer depths of the soil. They grow over the winter so that they need even more grass roots when they come back up closer to the surface next spring.
In spring, grubs are larger and stronger, making them more resistant to control products. In late summer and early fall, shortly after hatching, they are smaller, weaker and more vulnerable to control measures.
Grub control materials are sold at garden centers. But you have to haul them home and spread them. Our lawn care professionals can check for grubs and apply the most effective material available.
Gads! When I think that I am fortunate that we do not need to contend with them very often, I remember that we have gophers. We could have grubs right now, but would never know while pursuing the gophers!