Lawns will start to show signs of grub damage in late summer and early Fall. There’s no way to predict if a lawn will have grubs beforehand, or even how bad the damage will be.
Years with a wet June, like this one, tend to be much more favorable for having grubs. The spread of the Japanese beetle across the Midwest has also increased the likelihood of having grub damage. This is because the early life stage of a Japanese beetle is a grub and they can eat a lot of grass roots before hibernating for winter in the soil. So, how do you know if you have grubs and what can you do about them?
1. Look for the thin spots – Grub damaged lawns will have areas of thinning or dead grass in spots or large patches.
2. Pull back the sod – Grab a handful of the dead turf and pull it up. If the dead sod peels back easily grubs may have eaten the roots.
3. Look for the culprits – If active, white grubs will appear as “C” shaped plump white grubs just beneath the sod. They will be most numerous on the outer edges of the dead spots.
4. Watch the animals – Many times, raccoons or birds will find the grubs and move in, eating the grubs as they tear up the lawn.
Usually, one or 2 grubs will not cause much damage and treatment is not needed; however, in many cases, severely infested lawns can have as many 100 grubs or more per square yard and cause a tremendous amount of damage. While preventing grubs is much easier, there are options for killing grubs once they have taken over.
Actively feeding grubs can be killed with products containing Dylox. This is a granular product applied with a spreader. Immediate watering is required afterwards for the product to become effective. Typically grubs will begin to die in less than a day. Re-seeding can be done immediately after application.
Customers wanting an all- natural long term preventative plan to control grubs should consider using Milky Spore Granules. After a few years of applications your lawn will develop a natural biological grub control in the soil which will last up to 10 years.