Snow mold is a disease that causes problems on turf mainly in the springtime in our region. Two types which occur here are Grey Snow Mold and Pink Snow Mold.
WHERE DOES IT OCCUR:
Snow molds occur in most northern regions of Canada and can be found in our region. Most cool season grasses can be affected, while Fine Fescue is more severely damaged by this disease. Snow cover and wet weather causes the most severe cases of this disease.
CONDITIONS NEEDED FOR THE DISEASE:
Neglecting that last cut of the year is generally the best conditions for snow mold to occur. The tall grass bends over with the first snowfall and creates an ideal environment for the disease to flourish. Signs of the disease begin as small spots 2-4 inches in diameter. These gray-white patches can expand to three feet with a look similar to grayish cotton balls. The blades of the grass are bent over and may contain black or brown fungi, intertwined with the leaf blade.
Cultural practices are the best form of control for this disease. Ensure your lawn receives good fall fertilization with the emphasis on the potassium and phosphorus to encourage root development and disease fighting. Continue to mow your lawn well into fall lowering the mower deck until your last cut is at its lowest setting. Decrease watering to allow grass to "harden off" for the winter. Using a rake in the spring will break up the patches of snow mold and help your lawn recover more quickly. Bagging your first two cuts will also reduce the pathogens that can remain dormant between growing seasons.