Iron Chlorosis causes the blades of the grass to develop green and yellow stripes, or to turn completely yellow. It occurs in alkaline (high pH) soils with high phosphorus levels, and under cool and wet soil conditions.

St. Augustine grass is most susceptible to Iron Chlorosis.

Drought Stress

Grass affected by drought stress looks blue-green or silverish, and individual blades curl. Footprints remain in the lawn after you step on it. The soil under the lawn is dry.

Brown Rings

Brown patch first causes circular patterns of dead grass blades; in two to three weeks, new leaves may emerge in the center of the circular patch, giving diseased areas a donut-shaped appearance. The affected grass turns brown and grass blades rot and break off from the runners.

Take-All Patches

Take-all patch first appears as a yellowing of the grass and a darkening of the grassroots, followed by a thinning of the turf in irregular shapes. The darkening of the roots indicates rotting, and the roots can rot so extensively that the grass can be easily pulled up.