If your lawn looked fine in July and now has ragged brown patches that pull up like loose carpet, you’re not imagining it, and you’re not alone. Late summer is peak grub damage season across Maine, and homeowners from Hermon to Old Town are noticing the same thing right now: healthy green turf turning brown seemingly overnight.
Here’s how to tell whether grubs are the culprit, how to check for yourself in five minutes, and what to do about it before the damage spreads into fall.
The Telltale Signs Your Lawn Has Grub Damage
Grub damage looks different from drought stress or disease, once you know what to look for:
- Irregular brown patches that appear suddenly, often in August and September
- Turf that feels spongy or loose underfoot, as if it’s no longer anchored to the soil
- Sod that peels back like a rug, because the roots have been eaten away
- Increased digging by skunks, raccoons, or crows, who are hunting for grubs as a food source
- Patches that don’t green back up even after watering, unlike drought-stressed grass
The Carpet Test: Check for Grubs in Five Minutes
You don’t need to guess. Grab a spot at the edge of a brown patch and gently tug on the grass. If it lifts easily, like a loose carpet, with little to no root resistance, grubs have likely fed on the root system underneath. Peel back a one-foot section of turf and count the white, C-shaped grubs you find in the soil beneath it. Turf researchers generally consider more than 8 to 10 grubs per square foot enough to justify treatment, though a healthy, well-established lawn can often tolerate lower numbers without lasting harm.
Why Grubs Are Especially Active in Maine Lawns Right Now
Grubs are the larval stage of beetles, most commonly Japanese beetles and June bugs in the Bangor area. Adult beetles lay their eggs in moist turf in early summer, and by early August, those eggs have hatched into grubs that begin feeding heavily on grass roots. That feeding continues into October, which is exactly why lawns that looked healthy a month ago are showing damage now. Penobscot County’s mix of well-irrigated residential lawns and cooler fall soil temperatures creates ideal conditions for grubs to do the most damage right before winter dormancy sets in.
What to Do If You Find Grubs
Once grubs are confirmed, timing matters. Products applied earlier in the season target grubs preventatively, before they’ve caused damage. By August, most lawns need a curative approach that reaches grubs where they’re actively feeding, which is a different treatment window and product strategy than spring prevention.
Beyond direct treatment, a few practices help your lawn recover and resist future grub pressure:
- Core aeration relieves soil compaction and encourages deeper root growth, making turf more resilient to root-feeding pests
- Consistent, deep watering trains roots downward, away from the surface where grubs feed
- Overseeding damaged patches in early fall, Maine’s ideal seeding window, helps thin turf recover before winter
Lawn Dying in Bangor, Hermon, Brewer, or Old Town? We Can Help
TruGreen Bangor has been diagnosing and treating grub damage in Penobscot County lawns since 1996. We serve homeowners throughout Bangor, Hermon, Brewer, Orono, Old Town, Veazie, Hampden, Glenburn, Holden, and Eddington, and we know how differently grub pressure shows up on a shaded Brewer lot versus an open, sunny lawn in Hampden. If your grass is thinning and pulling up loose, our technicians can confirm grub activity and recommend the right treatment for where you are in the damage cycle.
Concerned about your lawn? TruGreen Bangor, locally owned and operated by the Windle family since 1996, offers free lawn evaluations for homeowners throughout Bangor and Penobscot County. Call 207-848-3335 to schedule yours.
Learn More
UMaine Cooperative Extension: Lawn and Turf Insect Pests
University of Illinois Extension: Managing White Grubs in Turf
Michigan State University Extension: Grub Control Timing
