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Snow Mold: A Wintertime Threat to Your Lawn

Bread can go moldy. So can cheese, meat, and many other food items. But lawn grass? Yep, that too. In fact, there’s a type of mold that can develop on lawn grass during the dead of winter. It’s called, appropriately enough, snow mold.


Snow mold tends to show up as circular grayish or pinkish patches (the color depends upon the particular strain of the disease attacking your lawn). The circular patches may be up to a foot in diameter, or in some cases, even larger. Snow mold can really knock the appearance of your yard for a loop. That’s the bad news.

The good news is that the disease is usually not serious – at least so far as the long-term health of your lawn is concerned. Though snow mold may uglify your yard during the winter, warmer springtime weather will generally result in a full recovery.

Where There’s Snow, There May Be Mold

Snow really is a factor in helping the disease gain a foothold in your yard. Long periods of snow cover offer ideal conditions for incubating and spreading the disease. That’s because the pathogens that cause the disease are happiest during periods of cool, wet weather.

After a long period of snow coverage, symptoms of snow mold are often revealed as the snow finally melts away.

Fighting Snow Mold 

There are several steps you can take to help prevent the occurrence of snow mold in your lawn. Lots of thatch or organic debris left on your yard going into winter will increase the likelihood of a snow mold infestation. So keeping your lawn mowed and free of leaves will help. A good height to target for your lawn grass going into winter is 2.5 to 3 inches.

You can also help to prevent the occurrence of the disease by making certain that no areas of your lawn are under snow cover for longer than necessary. Try to avoid placing deep piles of snow on your lawn due to snow removal activities – along driveways, for example, or sidewalks. Those piled-up areas will be under snow cover longer, and be at greater risk of a snow mold infestation.

If snow mold strikes, you can hasten your lawn’s recovery from the disease by regularly raking the infected areas. Raking helps to break up any matting that may be reducing the flow of air within the infected turf.

And while there are chemicals that can be effective against snow mold, most experts recommend that homeowners avoid using them. The risk/reward ratio just doesn’t justify it, since snow mold usually disappears with warmer weather. Commercial facilities such as golf courses, however, often resort to regularly scheduled applications of fungicides in an effort to prevent the occurrence of snow mold.

It May Look Really Bad, But…

If your lawn is stricken with a snow mold attack, it might get to looking pretty bad in places. A bad case of snow mold can be quite disheartening to a homeowner, making a long and dreary winter all the more difficult to endure.

But take heart – springtime cures lots of ills. As the weather warms and your lawn greens up, the snow mold likely will soon be no more than an unpleasant memory. Until next winter, anyway.

This entry was posted on Wednesday, February 5th, 2014 at 5:10 pm. Both comments and pings are currently closed.

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