Mystery Dry Patch in Lawn: Investigating Localized Soil Moisture Loss

4×4 ft area, 1.5 ft deep, extremely dry/dusty soil. Shrub (tulip flower bush) died. Rest of lawn fine. No irrigation. Other plants OK without watering. Puzzled by isolated dry spot.

Most Likely: Irrigation/Rain Shadow

• Something blocks rain/sprinkler: roof overhang, dense canopy, structure.
• Even without irrigation, rainfall should wet uniformly.

Simple Test: Pie Pan Audit

1. Place weighed-down aluminum pie pans: one in dry spot, several in normal areas.
2. Run sprinkler or wait for rain.
3. Measure water in each. Dry spot pan = less water = blocked.

Other Possibilities

• Buried debris (construction waste) creating hydrophobic layer.
• Tree root competition (large tree nearby?).
• Soil texture anomaly (coarse sand lens draining fast).
• Hydrophobic soil (organic coating on sand particles).

If Rainfall Is Even

Dig test hole in dry spot vs. normal. Compare soil texture, color, roots, debris. Hydrophobic soil: water beads on surface, won't penetrate. Fix with wetting agent + organic matter.

Bottom Line

Start with pie pan test. It's free, easy, and usually reveals the culprit.