Moldy Sod Problems

Pink Snow Mold

• Pink snow mold, or Fusarium patch, is caused by fungal spores, according to North Dakota State University. This disease causes yellowish patches of infected grass to appear after snow melts. Eventually, patches spread, take on a bleached-out appearance and turn pink when wet. While pink snow mold in spring may not respond to a fungicide, it's important to apply fungicide when you first notice symptoms the disease.

Gray Snow Mold

• Gray snow mold, or Typhula blight, appears in the spring when snow is melting off the lawn. The disease produces gray colored patches of lawn that be over 40 inches in diameter. Upon close examination, gardeners may notice brown to black mycelial masses on the blades of their grass within the gray mold, according to the University of Rhode Island. Gray snow mold fades under the sun, so treatment is not generally required.

Prevention

• Prevent snow molds from infecting your grass by mowing your grass until it goes dormant in the fall months. A fall application of nitrogen can repel snow mold diseases. Apply the fertilizer six weeks before your lawn goes dormant for the winter, recommends the University of Rhode Island. Avoid using over a pound of nitrogen per 1,000 square feet to prevent a new flush of lawn growth that can become damaged during the winter.

Slime Mold

• Slime mold, very different from snow molds, will not harm grass if it is removed from the grass blade's surface. Signs of slime mold include a dark oil-type substance appearing on your lawn. In fact, it may look as though someone spilled oil on your sod, according to the website Walter Reeves. To remove slime mold, wash off your lawn in the morning. Avoid watering in the afternoon to discourage other fungal diseases from developing.