Symptoms
- Brown or bare patches after mowing, especially on high spots
- Blade marks visibly gouge the dirt in places
- Happens mostly on bumps, slopes, or uneven ground
- Cut looks fine on flat, even areas
Likely causes
- CommonCutting height set too lowA deck height under 2.5–3 inches leaves little margin for ground bumps.
- CommonUneven lawn terrainDips and mounds mean a fixed deck height will scalp the high spots.
- PossibleLow tire pressureSoft tires let the deck sag closer to the ground than intended.
- PossibleWorn deck rollers or anti-scalp wheels missingThese small wheels are designed to prevent the deck from digging in on bumps.
What to do
- Raise the cutting height by one or two notches, especially for the first mow of the season.
- Check and correct tire pressure on all wheels to the manufacturer's spec.
- Inspect for anti-scalp wheels or deck rollers, if your model has them, and replace any missing or worn ones.
- Walk the lawn and note high spots; consider top-dressing or leveling significant humps and dips over time.
- Mow in a different direction on uneven areas to reduce repeated scalping in the same spots.
- Recheck the cut after adjustments on a small test area before mowing the full lawn.
Tools and parts
- Tire pressure gauge
Anti-scalp wheel kitSearch: “mower deck anti-scalp wheels”
When to call a pro
If scalping continues after height and pressure adjustments, a mower shop can check deck level and hanger brackets.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.