Winter's Wrath

So far this winter season, mother nature has been less than kind to us here at Kamloops Golf Club. Unlike last winter where we had snow cover from December till March with temperatures remaining steady throughout most of of the season. This year we had an early snowfall in November, which partially melted. This created ice in places where the snow melt pooled while leaving other areas of turf exposed to the elements of winter. This was followed by freezing rain which added to the formation of ice. I have recorded the major weather events that have potential to affect turf quality so far:

Nov 18 -- 3cm snow, wind 50km/hr, -5C
Nov 29 -- 1.5mm Freezing rain, +2C
Nov 30 -- 2mm Freezing rain, +2C     ICE FORMATION
Dec 1 -- 1.5mm Freezing rain, +5C  
Dec 2 -- wind 80km/hr, -7C, turf exposed
Dec 7 -- temperature dipping to -21C, turf exposed  DESICCATION POTENTIAL
Dec 11 -- 6cm snow
Dec 20 -- 9cm snow
Dec 27 -- 1mm freezing rain, +4C   ICE FORMATION                                        
Dec 28 -- +5C
Dec 29 -- 3cm snow
Jan 2 -- +4C    
Jan 4 -- +5C    FREEZE-THAW CYCLES
Jan 5 -- Temp down to -11C
Jan 10 -- (Forecast) +6C

With these records we can look at just how they may affect the quality of our turf when we come out in the spring.

There are four ways that the wrath of winter can cause damage to turf:

1) Disease
2) Ice/ Anoxia
3) Wind/cold Desiccation
4) Crown Hydration

Disease

When Superintendents talk about disease on turf, we are not talking about heart disease or lung cancer, for the most part we are talking about the formation of fungus that causes damage or death to the plant. In the case of winter there are two main fungi that are prevalent: Pink Snow Mold (Microdochium nivale) and Grey Snow Mold (Typhula incarnata). Pink snow mold thrives in moist cool envirnments, such as late fall and early spring. Snow melt can also contribute to the formation of pink snow mold. Grey snow mold thrives under the warmth and moisture of extended snow cover, both are capable of causing large areas of turf to die.

Snow Mold, 4th Tee surround, Spring 2013

To prevent the formation of these snow molds we apply a chemical fungicide in the late fall to protect through the winter. At Kamloops Golf Club we maintain environmental stewardship and only select products that have been proven to be safe for the environment. We are always seeking the newest technology to reduce our impact on the environment. As long as these products are applied successfully, they generally offer good protection against disease.

Ice/ Anoxia

The formation of ice over turf is also very destructive. As plants are living things, they require oxygen and release carbon dioxide to survive. Yes, you could say plants breathe too. When a solid layer of ice forms over the turf, the plant cannot take in oxygen and the carbon dioxide that is released remains trapped under the ice creating a toxic environment. These condition are known as Anoxia and can lead to turf death. However, the grass plant is smarter than it looks. In the fall the grass undergoes a process called "hardening off" as it goes dormant in preparation for winter. The plant stores carbohydrates to feed itself and to help to lower the freezing temperature of its cells. The accumulation of these carbohydrates helps the plant survive under ice for a certain amount of time. Poa annua is said to be able to survive for 30 days under ice cover, while bentgrass is 120 days.

Ice 11th Fwy, Dec 2013

Ice 11th Fwy, Dec 2013

 Ice chipping, 18th Fwy, Dec 2013

Preventing the formation of ice is very difficult, if not impossible. As snow accumulates and melts, it may freeze at the soil surface, creating ice. Not to mention the troubles freezing rain presents. We can attempt to chip the ice away, which often causes more damage than just leaving it alone. We can try and melt the ice with black sand, rubber crumbs etc. but then we leave the turf exposed until more snow cover occurs. Sometimes the best thing to do with ice, is just wait it out.

At Kamloops Golf Club we underwent a conversion from Poa to Bentgrass on our greens, tees and fairways during the renovation of 2010, but poa (the native grass) has been creeping back in since then. My philosophy is that if bentgrass is the grass we are trying to grow, and it can survive for 120 days (4 months) under ice, where poa can only survive for 1 month, let the ice kill off some poa, while the bentgrass stays alive. In doing this we can expect to do some re-seeding of areas in the spring, but will ultimately reduce the percentage of poa in our turfstand.

Wind/Cold Desiccation

Wind chill temperatures can create some of the most wide spread turf damage of all. At Kamloops Golf Club we are especially subject to this type of damage, as temperatures can reach below -20C and winds rolling off Kamloops Lake can gust over 80km/hr, creating a deathly wind chill. This is one of the primary reasons we decided to undergo a renovation and conversion to bentgrass in 2010.

Example of wind/cold damage

Much like living under ice, bentrgrass has a much better winter tolerance to wind and cold than poa annua. However, bentgrass is not invincible and can sustain damage in extreme weather, as can any living thing.

To protect and wind/cold desiccation we topdress the greens with a layer of sand to protect the crown/growing point from direct wind and cold. Snow cover also provides very good protection for the turf. The snow insulates and keeps temperatures at the surface closer to 0C and -1C, while at the same time, provides a cover from the wind. Unlike ice, snow is not a solid layer, so gas exchange of the turf is still able to take place.

Crown Hydration

The Grass Plant

As I mentioned, the crown of the grass plant is the point of growth, leaves and shoots grow up, and roots grow down. This makes it the most important part of the plant. If the crown dies, the plant dies. We also discussed how the turf prepares itself for winter and goes into dormancy. When temperatures during the winter and late spring rise above zero and cause snow to melt, the plant may take in some water, also known as hydration. If this happens over an extended period of time, the crown may begin to break dormancy and grow. The plant thinks spring has arrived and its time to wake up from winter. The crown now active, is much more susceptible to damage. If the temperature at the surface drops below zero again, the water in the crown may expand and cause the cell walls to rupture, causing death of the plant. Freeze - Thaw cycles are one of the most damaging forces to turf and can cause wide spread death to a turfstand.

Crown hydration damage example, spring re-seeding

Crown hydration is also very difficult to prevent. Some superintendents remove the snow in the late winter/early spring if they feel the temperatures will remain above or around 0C. The risk with this is if the temperature drops again and the turf is left exposed to desiccation as it is breaking dormancy.

As you can see, turfgrass faces some extreme challenges during the winter. As Superintendents we are often at the mercy of Mother Nature, and try as we might, sometimes we may end up doing more damage than if we let nature take its course.

Through the weather records above we can see that we have undergone many of processes in which turf may be damaged. Does that mean we may lose large amounts of turf this year? Not necessarily... We still have had a consistent snow cover since December 11, and although there are patches of ice remaining underneath, our conversion to bentgrass should offer some extended protection. We expect to do some re-seeding in the spring, but we do that every spring regardless. We can remain cautiously optimistic, with some luck, a nice warm spring will bring another great start to our season of golf at Kamloops Golf Club. We are looking forward to getting things going in just a few months.