The term “winterkill” is a broad classification that covers many forms of turf damage that result from cold weather. Some causes of this type of damage are crown hydration, desiccation, low temperatures, ice sheets and snow mold. It can be difficult to distinguish which type of damage your lawn is exhibiting. Here are some tips on how you can identify winter damage on your lawn.
Crown Hydration This type of damage typically occurs when a few warmer days are followed by a rapid freeze, most often in late winter/early spring. As plants begin to hydrate in warmer temperatures, then a freeze occurs, that water within the plant can form ice crystals within the crown that can cause permanent damage.
Desiccation is when leaves or plants are killed by drying, cold winds because the dormant grass is not protected by snow cover.
Direct Low-Temperature Kill occurs when warm late fall temperatures drop precipitously to very cold early winter temperatures. When grass doesn’t have time to go through the typical dehydration process as the seasons change, it becomes susceptible to this type of damage.
Snow Mold comes in two varieties: gray snow mold, which requires extended periods of snow cover; and pink snow mold, which can occur with or without snow cover.
Ice Sheets are the result of the melting and refreezing of snow, and are most common in areas which are poorly drained.
It can be challenging to recover from any of these types of damage, and often it is necessary to wait until the unpredictable days of early spring weather have passed to determine the extent of the damage. But as with any damage to turf, diagnosing the problem is the first step in recovery.