My sincere hope is that everyone had a wonderful holiday season and is ready to leave 2020 behind and move on to 2021. Upon reflection after this first season, I would like to thank the folks at Nemadji for allowing me the opportunity to apply my trade at the golf course. I am pretty passionate about my work and enjoy the challenges that Nemadji has presented. I truly appreciate how supportive everyone has been to our efforts-the crew, the customers, my co-workers in all departments, KemperSports, and the City of Superior. We are all in this together and without this kind of unified support we will not be successful in achieving our goal of making Nemadji the best facility that it can be.
The biggest challenge faced by golf courses in our area of the country is the loss of turf over the winter due to a variety of factors such as little to no snow cover during excessively cold periods, excessive winter rain followed by a deep freeze, extreme amounts of snowfall that linger into the spring, and multiple freeze thaw cycles-particularly at the end of winter/early spring. So far this winter at Nemadji, we have experienced really none of these scenarios and for that I am very thankful. While the snow was a little late in coming, we really did not have any cold weather while the turf was exposed which might result in desiccation. We did have a small amount of rain in December but nothing too concerning and so ice, though it may be an issue on some smaller areas, should not be a problem. Still too early to tell regarding snow amounts. If we do get record breaking amounts of snow in the next few months there is a chance that disease pressure in the form of snow mold might become too much for our October applied winter chemical applications but I feel pretty good about the efficacy of modern chemistry and so I am not too concerned there. My experience has been that turf usually grows through snow mold damage relatively easily anyway. This leaves the final scenario-one in which a very warm snow-melting period is followed by a very cold snap. In this turn of events, crown hydration could be an issue. This menace in particular is diabolical in that damage may not be as evident initially as it is with other winter issues but rather begins to manifest itself in subsequent weeks. Very sneaky. All this being said, predicting prevalence of winter injury is always an uncertain science. All I can say is so far, so good.
For those of you interested, I have this older article (still current information) which gives a short explanation about this topic.
Winterkill of Turfgrass • E0019TURF
K. W. Frank
“Winterkill” is a general term that is used to define turf loss during the winter. Winterkill can be caused by a combination of factors including crown hydration, desiccation, low temperatures, ice sheets and snow mold. Because of the unpredictability of environmental factors and differences in other factors such as surface drainage, the occurrence of winterkill on golf courses is variable and can vary greatly between golf courses and even across the same course.
Crown hydration
In general, annual bluegrass (Poa annua) greens and fairways are the most susceptible to crown hydration injury. During the warm days of late winter, annual bluegrass plants start to take up water (hydrate). Potential for injury exists when a day or two of warm daytime temperatures in late winter is followed by a rapid freeze. The most common time for winterkill associated with crown hydration and refreezing to occur is during the late winter and early spring when there is snowmelt or rainfall and then refreezing of the water that has not drained away. Crown hydration is a problem during these events because ice crystal can form in the crown of the plant, rupture the plant cells and ultimately cause the plant to die.
Annual bluegrass is more susceptible to crown hydration injury than creeping bentgrass because it emerges from dormancy and begins taking up water. Creeping bentgrass remains dormant longer and, therefore, does not take up water and is not as susceptible to crown hydration injury during the late winter.
Desiccation
Winter desiccation is the death of leaves or plants by drying during winter when the plant is either dormant or semidormant. Desiccation injury is usually greatest on exposed or elevated sites and areas where surface runoff is great (Beard, 1973). Winter desiccation injury to turfgrass in Michigan is normally rare, though sites similar to those described above can be prone to desiccation injury on a regular basis.
Low-temperature Kill
Low-temperature kill is caused by ice crystal formation at temperatures below 32 degrees F. Factors that affect low-temperature kill include hardiness level, freezing rate, thawing rate, number of times frozen and postthawing treatment (Beard, 1973). Soil temperature is more critical than air temperature for low-temperature kill because the crown of the plant is in the soil. It is difficult to provide absolute killing temperatures because of the numerous factors involved. Beard (1973) provided a general ranking of low-temperature hardiness for turfgrass species that were autumn-hardened.
Low-temperature hardiness | Turfgrass species |
Excellent | Rough bluegrass |
Creeping bentgrass | |
Good | Kentucky bluegrass |
Colonial bentgrass | |
Medium | Annual bluegrass |
Tall fescue | |
Red fescue | |
Poor | Perennial ryegrass |
Ice sheets
Ice sheets are often blamed for killing turf when, in fact, it is crown hydration and subsequent refreezing that has resulted in the kill. The reason for the confusion is that, as snow melts and refreezes, creating ice sheets, the ice sheets are often in poorly drained areas where crown hydration can occur because of the standing water. As the ice sheet melts away, the area damaged closely mirrors where the ice occurred, and therefore, the conclusion is that ice sheets caused the kill. Beard conducted research on ice sheets on three turfgrass species: Kentucky bluegrass, creeping bentgrass and annual bluegrass. Kentucky bluegrass and creeping bentgrass survived 150 days of ice cover without significant injury; annual bluegrass was killed somewhere between 75 and 90 days of ice cover (Beard, 1998). The author concluded that cause of death for the annual bluegrass was most likely from toxic gas accumulation under the ice sheet.
Snow mold
The two diseases commonly called snow mold are Typhula blight (gray snow mold) and Microdochium patch (pink snow mold). Gray snow mold requires extended periods of snow cover; pink snow mold can occur either with or without snow cover. If snow mold injury is a recurring problem, preventive fungicide applications are the best control option.
Literature Cited
Beard, J.B. 1973. Turfgrass: Science and Culture. Englewood Cliffs, N.J.: Prentice-Hall.
Beard, J.B. 1998. Winter ice cover problems? TURFAX. 9(1):1-2,5.
On to another winter topic, after this last wave of snow we noted some snowmobile traffic on the golf course. This can lead to issues if it gets too out of hand so assistant superintendent Brian Wallin and I have done some snow fence work to help protect some of the most vulnerable parts of the golf course. That being said, Nemadji is a big place and keeping snowmobilers determined to drive on the property off the golf course with barriers is not practical. All we ask is for people to spread the word for snowmobiles in the area to stay on the trails and stick to ditch riding on the perimeter-show the respect to the golf course that the community desires. Winters are tough enough on golf courses without the added stress of snowmobile traffic.
Brian Wallin January 12, 2021
5 East Snow Fence December 12, 2021
Thank you for your support and I look forward to working with everyone in 2021.