Grubs and Skunk Damage: Why Something Is Digging Up Your Guelph Lawn

What grubs are, and why late summer is their season

Grubs are the larvae of beetles — mostly European chafer and Japanese beetle in our part of Ontario. The adults fly and lay eggs in lawns through early-to-mid summer. Those eggs hatch into small white larvae in mid-to-late summer, and the young grubs spend the next several weeks chewing through grass roots just under the surface. That feeding is why a lawn can suddenly brown and loosen in August even where you’ve been watering.

The grubs themselves are unmistakable once you find them: fat, white, C-shaped, about the size of your thumbnail when grown, usually curled up in the top inch or two of soil. Find a few and the mystery is solved.

Is it actually grubs? The tug test

Digging animals are the loud symptom, but they’re not proof on their own — skunks also root for earthworms and other insects. The real confirmation is in the soil. Grab a browning or loosened patch and pull up on the grass. If it lifts away in a sheet with almost no roots holding it — like peeling sod off the ground — grubs have eaten the roots out from underneath. Healthy turf resists; grub-damaged turf rolls back like a rug.

Then look underneath. Peel back a square foot of loose turf and count the white grubs in the soil below.

• Turf lifts like loose carpet with no root resistance — the classic grub signature.
• Skunk digging: small, cone-shaped holes and flipped divots, appearing overnight.
• Raccoon damage: larger sections rolled right back, often near garden beds.
• Birds working the lawn hard in the morning — another sign of something under the surface.
• A handful or more of white, C-shaped grubs under a square foot of turf usually means the population is worth acting on.

Why the damage looks worse than the grubs alone

Here’s the frustrating part: on most Guelph lawns, the animals do more visible damage than the grubs. The grubs thin and brown the turf, but a skunk or raccoon that has learned there’s a buffet under your lawn will shred it methodically, night after night, flipping large areas to get at the larvae. The lawn ends up torn apart by the hunters, not just the pests.

That’s also why simply chasing the animals off doesn’t work for long — as long as the food source is there, they keep coming back. Dealing with the grubs is what actually stops the digging.

What to do about it right now

The honest first step is to confirm you have a real infestation, not one lucky skunk finding a few worms. If the tug test passes and you’re counting grubs, then it’s worth acting. If the lawn is holding firm and you found one or two grubs, leave it — a thick, well-rooted lawn shrugs off a light population, and the single best long-term defence against grubs is dense turf that recovers faster than they can damage it.

• Keep the lawn thick and deeply rooted. Mowing at 3 inches and watering deep and infrequent grows the root mass that makes a lawn resilient to grub feeding in the first place.
• Don’t bother reseeding torn areas in the heat of summer — grass won’t establish, and any repair now can just get dug up again while the grubs are still active.
• Plan the real repair for early September. Our best seeding window in Guelph lines up almost perfectly with the tail end of grub season: rake out the dead turf, level it, overseed, and the cool, damp fall does the establishing for you.
• If damage is severe and recurring, that’s the point to look at a proper grub-control product applied at the right time — timing matters more than the product, and it’s easy to spend money applying it in the wrong month.

When to bring in a crew

Grub damage is one of those problems that’s genuinely hard to read from a photo — torn turf can look identical whether it’s a minor visitor or a lawn that needs rebuilding. We’re on lawns across Guelph every week through late summer, so we can usually tell in a few minutes on site whether you’re looking at a couple of skunk holes or an infestation that warrants a fall renovation plan.

If your lawn is getting torn up and you’d rather not guess, we’re glad to take a look. We can handle the whole fix — assessment now, then aeration, overseeding and a proper repair in the ideal September window to rebuild what the grubs and diggers took out. Quotes are free, mowing starts at $40 per cut including trimming, edging and blowdown, and you can reach us at (519) 731-5274.