‘Tis the Season – Snow Mold comes to New England

The end of winter is here.  We are excited about longer days, blooming flowers, and shout a long awaited hello to the warm sunshine.

Unfortunately, this is the time of year snow mold rears its ugly head in our dormant lawns.  The UMass Extension and Rhode Island Cooperative Extension explain the symptoms of, and how to conquer, this menace so we can get our lawns ready for wigglin’ toes and puppy dog noses.

You’ll see the first insidious sign as small circular patches on the lawn in sizes of 3 – 12 inches in diameter.  Sometimes, if the mold takes hold, patches blend together to cover large sections of the lawn.  These molds are active in the colder, wetter times of the year, surviving and even thriving beneath the snow.  Visually, “…web-like mycelium of pink snow mold (Microdochium nivale) may initially look white and mature to a faint pink to salmon color.  Gray snow mold (Typhula spp.) is white to gray in color.”

As temperatures rise, the snow melts, and the sun beats down on awakening lawns, New Englanders rejoice.  However, with spring weather patterns, snow molds become increasingly unhappy.  Most of the time, the normal emergence of warmer, sunnier weather is enough to kill snow molds.  Yard clean up, among other steps, is your best bet for snow mold deterrence and lush lawns.

What to do next if you have snow mold?  Determine the type of mold, either pink or gray, that has infected your lawn.  The gray mold doesn’t do extensive damage, and typically the grass recovers quickly.   Pink snow mold gets to the heart of the grass crowns and roots causing, sometimes, irreparable damage.  Often times, both types of snow molds can be found in our lawns.  An essential step for snow mold prevention is taking away its comfortable home — rake up dead leaves and clean debris from lawns.  A good choice of seed for replanting in areas that need to be cleaned out is Kentucky bluegrass, which is less susceptible to snow mold infection.

Happy Spring to you and your families.

D. A. Boss, Gordon Mycology Laboratory, Inc. 2009