How to treat Snow Mold in a lawn
What Is Snow Mold?
Gray snow mold can be seen after the snow melts in a lawn. This is seen after the lawn has had a long period of snow coverage.
Why Chemical Treatments for Snow Mold are Not Necessary
Snow mold will die very quickly when exposed to sunlight or the area dries out. Gray snow mold activity stops when the surface dries out or the temperature exceeds 45° F. Pink snow mold activity may continue during wet weather in the fall and spring, as long as the temperature is between 32° F and 60° F. Gray snow mold is common in Colorado and pink snow mold is not very commonly found in Colorado lawns.
Symptoms of the snow mold damage appear in the lawn long after the snow mold is no longer active. Most homeowners notice the snow mold damage as circular, straw colored patches of lawn that are surrounded by green grass. The damaged areas often have a matted appearance and discoloration.
How to Prevent Snow Mold from Causing Damage to a Lawn?
The damage caused by snow mold is seldom serious. If the snow mold is minor the infected areas will be slower to green-up compared to the other parts of the lawn. The snow mold dies and sits on top of the grass. The dead mold blocks the sunlight from reaching the turfgrass, preventing it from producing chlorophyll.
To cure and prevent snow mold damage the homeowner should gently rake the affected areas of the lawn with a leaf rake. The raking breaks up the snow mold allowing sunlight to reach the grass. The lawn will begin to green-up within a few weeks after the snow mold has been broken up or removed from the top of the grass.
In severe cases the snow mold can cause major damage. This only occurs if the snow mold is not broken-up or removed. If the snow mold is left on top of the lawn for too long then the grass can die. In severe cases where permanent damage does occur, a top seeding package may be required to repair the damaged lawn. Fungicide applications are unnecessary because they will not prevent damage to the grass. Breaking up the snow mold is the only effective way to prevent damage to the grass.
Damage from snow mold tends to be on the north side of properties or in areas where the lawn does not get a lot of direct sunlight. Although it is possible in a very snowy and cold winter, south facing slopes usually do not suffer from snow mold damage.
What Does Snow Mold Look Like?
This is what snow mold looks like when it is still alive and growing.
This is grey snow mold in a lawn. It looks like cotton and has a sticky feel to the touch.
This is very fresh snow mold. This will die very quickly after exposure to sun and air.
The snow mold damaged all the areas where the grass is not green. There is some small green grass growing between the snow mold damaged areas.
Gray snow mold damage on grass a few weeks after the snow mold died.
This is a close up of what snow mold looks like on grass a few weeks after it has died.
This is a very common look of what snow mold damage looks like. Snow mold damage is not usually noticed until sometime in April.
Snow mold damage is not usually noticed by the homeowner until a few weeks after the lawn green up in the spring.
All the brown spots in the lawn are where the grey snow mold was covering the grass. The snow mold stops sunlight from reaching the grass.