Winterkill is an easy problem to define but difficult to understand. Winterkill simply put, is when turf dies during the winter. However, understanding the mechanism’s that cause winterkill whether it be ice, crown hydration, low temperature kill or desiccation is not that simple. Creating effective prevention strategies and formulating actual recovery tactics can be complex, time consuming and at times experimental.

What causes winterkill?

Winterkill is a catch all term describing winter injury to turf that can occur through a variety of circumstances. These can be ice cover or suffocation, crown hydration (freeze thaw which includes rapid thawing and then rapid freezing), low temperature injury and desiccation (drying out of turf). Sometimes identifying the causes of winterkill can be difficult because winterkill may be caused by one mechanism or by a combination of environmental situations that act simultaneously.

(Image) 13^th Green, The Oaks- Ice Damage

Can winterkill be prevented?

At this point, there is no silver bullet that prevents winterkill. Scientists at universities around the country along with the USGA have made great strides in breeding turf grasses that can have improved tolerances of winterkill mechanisms. New bentgrass varieties such as A-4, and G-2 have much better winter protection tendencies which we see on the greens at The Oaks, than Poa Annua greens which is highly susceptible to winterkill which is predominate at Candia Woods. Golf course superintendents are not able prevent winterkill, but they can implement a variety of agronomic programs that give playing surfaces a better chance of surviving the winter. Common strategies can include proper fall fertilization, raising mowing heights during the fall, reducing shade (tree/brush removal) improving drainage and covering greens with synthetic covers.

(Image) 16^th Green, The Oaks- Snow Removal- Early Spring

What are the most effective recovery techniques?

Winterkill damage can range from minor to severe. Golf course superintendents use a variety of techniques to help recover lost turf such as overseeding and sodding with bentgrass, properly timed fertilizers, traffic restrictions, temporary greens to keep traffic off sensitive areas and the use of synthetic covers to help warm the cool soil for seed germination.  Winterkill is a seasonal visitor that no golf course wants to see, the most important aspect from a golfer’s standpoint is understanding that patience will be necessary for recovery and that superintendents and scientist are diligently working hard to understand and overcome an age-old problem.