After the long, cold winter, it's a beautiful sight when your green lawn appears once again. But you might notice unsightly grayish circles all over your lawn, a sign that your lawn has snow mold.
According to Kelly Burke, the About.com expert of lawn care, "Snow mold is a fungal disease that appears in early spring as the snow melts." There are two types: Grey snow mold (Typhula blight) and pink snow mold (Fusarium patch). Fusarium patch appears to have a pinkish color of weblike growth.
Dead, matted grass in circular patterns, as small as 3 inches and as large as 12 inches, are the telltale signs of snow mold. "Depending on the severity of the outbreak," says Burke. "The circles can coalesce and become a large mass." And it's not uncommon to see grey and pink snow mold occurring together.
Snow mold circles are "caused when there is an extended period of snow cover on ground that is not completely frozen," says Burke. They can occur due to late-summer lawn fertilization, causing ample lawn growth late in the season. They are also formed under leaves or long grass left on the lawn all winter.
The experts at Scotts lawn care say, "With a few preventive steps, you can reduce the likelihood that your lawn will be attacked by this disease." Here are some prevention and maintenance tips:
--Know your region's risk for snow mold growth. According to the Scotts experts, grey snow mold likes cold, damp weather with temperatures around 30-40 degrees Fahrenheit for an extended period of time.
--Mow before the snow. Since long grass is a breeding ground for grew snow mold, cut your lawn just a bit shorter than usual before the snow arrives.
--Don't let organic material pile up. Mats of leaves and long grass clippings can bring on snow mold circles. "In the fall, use your lawnmower to mulch leaves into the lawn," say the Scotts experts. And rake up those lawn cuttings to add to your compost bin.
--Take it easy on the nitrogen. While some lawn foods promote fast-release nitrogen as a way to green up your lawn, too much can feed the growth of snow mold. Choose instead a low-nitrogen, slow-release lawn food, such as a winterguard variety, that will give your lawn extra nutrients without the excess nitrogen.
--Manage thatch levels beneath the surface of your lawn. Thatch is a thick layer of organic materials -- shoots, stems and roots -- that grows beneath your grass. A thicker layer of thatch could starve your lawn of nutrients and provide a ready environment for snow mold growth.
--Seek guidance about fungicides for your lawn. Burke says that while fungicides are available for the prevention and treatment of snow mold, they might not be recommended since snow mold damage is often superficial. In many cases, once the area has dried, the infection can die down and new grass will grow, renewing the lawn area affected.
--To speed up your lawn's recovery, you may lightly rake the affected areas to encourage drying, and apply some extra grass seed to grow new, healthy turf.
--In extreme snow mold cases, you may be able to repatch affected lawn areas to remove the blight and help create a circle-free, lush, green lawn.