If you find yourself sneezing and wheezing with a stuffy head this spring, it cold very well be the result of snow mold and not a cold.

Snow Mold is a lawn disease caused by two principle fungal culprits: gray snow mold  (Typhula spp; also known as Typhula blight) and pink snow mold (Microdochium nivalis, also known as Fusarium patch).  These spores or fungal structures begin to actively grow when the temperatures beneath snow cover range from slightly below freezing to about 45°F.

The Weather Network says that damage is usually concentrated to small patches of dead grass, but some fields can contain several such patches. The fungus can be visible, often looking like pink to grey cobwebs or small black masses.

Like any mold and fungus, snow mold can trigger physical reactions in humans and even our pets.  This would resemble a cold in people, but it's actually more of an allergy attack with symptoms like sniffling, sneezing, wheezing and headache.  Pets may first suffer from irritated, itchy skin.

Because the fungal spores travel through the atmosphere, avoiding a snow mold-induced allergy attack can be challenging, but there are things you can do.

First, if you notice snow mold on exposed grass, it can help to rake the grass to open up the blades which will help the area dry faster.  You could also mow infected areas shorter than normal once it's possible to do so.

Preventing snow mold is something you can do in the fall.  Two key things to do are:

  1. Rake and dispose of all your leaves before the snow flies.  Having leaves laying on your grass provide a great environment for snow mold to develop.
  2. Mow your grass to 2" just before snow takes over.  Having shorter grass makes it harder for snow mold to thrive and will allow your grass to dry faster in the spring.

Ultimately, the good news is that snow mold is temporary.  Most snow mold will go away once surfaces dry out or temperatures are steadily above 45°F, although pink snow mold can continue to grow on a moist lawn until temperatures surpass 60°F.