Brown Patches in Late Summer: Two Very Different Problems

Every August, Warren County homeowners notice brown patches in their lawns. The immediate assumption is drought stress — Ohio summers can be brutal, and grass does go dormant under heat and water stress. But brown patches in late summer can also be a sign of grub damage, and the two require completely different responses.

Treating drought stress with extra water when grubs are actually destroying your root system just delays the damage. Knowing which problem you have is the first step to the right fix.

What Grubs Are — and When They Strike

Grubs are the larval stage of several beetle species common in Ohio: Japanese beetles, June bugs, and masked chafers. Adult beetles lay eggs in lawns in June and July. Those eggs hatch into small white C-shaped larvae — grubs — that spend late summer and early fall feeding on grass roots just below the soil surface.

Grub feeding severs the connection between the grass plant and soil, killing the turf above. The peak damage window in Ohio is typically August through October, which overlaps with the hottest, driest part of the summer. That's why the two problems are so easy to confuse.

The Tug Test

The fastest way to tell grub damage from drought stress: grab a section of brown turf and pull. If the grass rolls back like loose carpet — roots completely detached from the soil — you have grubs. Drought-stressed grass, even if brown and dormant, stays rooted in the ground and resists being pulled up.

Other Signs of Grub Activity

Irregular patch shape: Drought stress tends to follow sun exposure patterns. Grub damage appears in irregular patches that expand outward as the colony feeds.
Spongy turf feel: Before the turf dies completely, grub-damaged areas may feel soft or spongy underfoot because the root system is compromised.
Animal digging: Skunks, raccoons, and birds dig into lawns to feed on grubs. If you're seeing unexplained digging in your yard in late summer, a grub infestation is likely the cause.
Visible grubs: Dig 3–4 inches down in an affected area. Finding 6 or more grubs per square foot indicates a damaging infestation level.

Signs of Drought Stress Instead

Grass turns bluish-gray or straw-colored uniformly, particularly in sunny areas
Footprints remain visible in the lawn hours after walking on it (low turgor pressure)
Turf feels firm — roots still attached — when you attempt to pull it
Grass recovers with irrigation or after rainfall

Timing Your Grub Treatment

Preventive grub treatment — applied in late June or early July before eggs hatch — is the most effective approach. Curative treatments applied after damage appears (August–September) are harder to time effectively but can still stop expanding infestations.

Once grubs have destroyed the root system, the dead turf typically needs to be overseeded or sodded to recover. Treating the grubs stops further damage but doesn't revive dead grass.

Towne Pest Control's Lawn Pest Program

We're the only company in the Warren County area licensed to treat your entire property — lawn and home together. Our lawn care program includes optional grub and insect control as part of our late spring/early summer application, timed to intercept newly hatched larvae before they cause damage.

If you're seeing suspicious brown patches right now, we can assess whether grubs are the cause and recommend the right treatment for your situation.

Learn more about our lawn care services or call (513) 932-3646 for a free estimate.

Grub Damage vs. Drought Stress: How to Tell the Difference in Your Ohio Lawn