LD

Lawn Dominators

Disease guide

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Diagnosis guide

Lawn fungus vs drought stress

Both can turn turf brown. The fix is different, so compare pattern, moisture, weather, leaf symptoms, and response before applying fungicide.

Drought stress clues

Drought stress often shows as wilt, folded or dull leaves, footprints that stay visible, and dry soil in the root zone. It may appear first on slopes, compacted areas, curb strips, or irrigation gaps. UMN recommends mowing at 3 inches or higher because taller turf shades soil and supports drought tolerance.

Fungal disease clues

Brown patch is favored by high humidity, warm nights, wet leaves, and lush growth. Dollar spot can show tan lesions with reddish-brown borders on leaf blades. Disease pressure is usually tied to weather, moisture duration, susceptible turf, and nitrogen management.

Do this before treating

  • Probe soil moisture in brown and green areas.
  • Inspect leaves closely, not just the patch from across the yard.
  • Review recent nitrogen, irrigation, and weather.
  • Photograph the same spot every 2 to 3 days.

If a fungicide is justified

Use label directions and rotate modes of action when repeat applications are needed. You can compare fungicide options on the Price Board, but diagnosis comes first.

Research and extension sources

  1. Penn State Extension: Brown patch disease
  2. Penn State Extension: Dollar spot disease
  3. University of Minnesota Extension: Mowing practices