Temperature Fluctuations Have Triggered Concern January 21, 2014 By Keith Happ

Temperature fluctuations this winter have been severe. It will take time to evaluate if significant turf damage occurred.

Since our last regional update we have been receiving phone calls from superintendents expressing concern about the health of cool-season and warm-season turf. During the first week of January temperatures dropped to record lows in most area of the region. Add the wind chill factor to the polar vortex we experienced and the limits of what grasses can tolerate was pushed to new extremes. Within seven days of the record lows, the temperature rose to 50°F. While it may have been a welcomed change to golfers, this tease of spring was not good for the grass. When the snow and ice melted there was reason for concern but not panic.

Areas of the golf course that had snow cover had an element of insulation. Soil temperatures at a two- to three-inch depth hovered at 32°F even when air temperatures were well below zero. Fortunately, the severe low temperature extremes lasted only for 24 to 36 hours. Research has demonstrated that creeping bentgrass is far more tolerant of cold temperatures than ryegrass or Poa annua.

For warm-season species, there are significant varietal differences with regards to cold tolerance.

The newer generation of bermudagrasses (e.g., ‘Riviera,’ ‘Latitude 36’ and ‘Northbridge’) were specifically developed for cold tolerance. No matter what grass you are managing it is hard to predict the aftereffects of these unusual weather conditions.

The turf needs to break dormancy before we can determine if there is damage. We still have a lot of winter weather ahead of us before consistent spring conditions allow for sustained turf growth. The grass needs sunlight and soil temperatures sustained at 50°F or more to grow consistently and the days are getting longer. For the short term, communicate concerns to course officials. Some have asked about using black sand or natural organic fertilizer to warm the surface of their greens. Black sand or sunflower seeds will melt ice accumulation and can be applied uniformly or site specifically. These products will not over stimulate growth. Conversely, fertilizer treatments on frozen turf are never a good idea.

If you have any questions please do not hesitate to contact one of our North-Central offices: Keith Happ, director, at 412-341-5922 or Bob Vavrek, senior agronomist, at 262-797-8743. Many superintendents have prepared very well for the winter weather. Plant protectants, anti-desiccants and heavy topdressing treatments have been completed. Continue to communicate concerns but don’t over react until the grass can grow.

It is not too early to plan to attend our Regional Conference at Oakmont Country Club scheduled Tuesday, March 11, 2014. Register online at Enter event code 31114. Credit cards are accepted for online registration.We make every effort to control costs by partnering with allied associations. The modest fee of $45 to attend provides a continental breakfast, a great slate of speakers covering a wide variety of topics and concludes with a buffet luncheon. Mark your calendars to join us; it is a great way to kick off the spring season!

Source: Keith Happ at ( or Bob Vavrek (

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