When brown wheel tracks or footprints show in a lawn during the warm summer months, the grass is drought-stressed. The grass will turn a dull bluish-green color and footprints won't "bounce back" within a few minutes.
Drought-stressed grass should be watered before any mowing, fertilizing, or play on the grass is allowed. Then, continue with normal or slightly increased watering. Mow often enough so that no more than an inch of grass is removed at any single mowing.
For more information please see PlantTalk script 1501, Brown tracks and wheel marks.
