Sunday, November 1, 2009

Frost Delay - Updated October 2011

"We can't tee off yet because of frost?
It's 35°, how can there be frost?"




Cold nights in the Spring and Fall increase the chance frost will form on the golf course turf. If carts or foot traffic are allowed on the course while there is frost, there may be significant damage to the turf. The damage to turf isn't from the frost itself. Frost is just a visual clue that it is cold enough for the turf grass plants to freeze. The damage occurs when it gets cold enough for the water inside the cells of the grass plant to freeze. Grass plants can survive freezing but if you walk or drive over the plant, the frozen cells will burst and the grass blades will die. Usually only the blades of the grass plant will die. The crown and roots of the plant will survive and re-sprout new grass blades in time but if the temperature is less than 30°, the crown of the grass plant can also die.

Frost forms when the air temperature at ground level is less than 32°. There are times when the thermometer reads higher than 32° and frost still occurs. This happens when the air temperature before sunrise is between 32° and 38°. As the sun begins to rise, it warms the air high in the sky and causes cold air to settle in the low areas on the ground and if the cold air is 32° or less, frost will form. There are also times when there is no visible frost because no dew formed at night but the water in the grass plant still freezes and is subject to damage from traffic.
The footprint above the golf ball shows how traffic on frozen turf can cause damage. Healthy, unfrozen turf will 'spring back' when walked on. This footprint crushed the frozen cells in the grass leaving a depressed area that will die and not recover for months. The turf on greens, tees and fairways is very susceptible to frost damage because close mowing in these areas exposes the plant crowns to freezing.

The rough areas are less susceptible to damage because the longer grass blades help insulate the plant crowns. Damage can still occur in the rough and when it does, it can take several weeks to heal the damage.

The length of a frost delay depends on many factors. If it is sunny and the wind begins to blow and mix the warm and cold air together, the delay can be as short as 30 minutes after sunrise. If it is cloudy, the delay can be a couple of hours. Often times on a clear night when it is cold enough for frost, clouds will form over the relatively warm water of Lake Michigan. The clouds will be several thousand feet high over the lake blocking the sun for up to an hour. This can make the frost delay longer by another hour or more.

Under some conditions we can reduce the length of a frost delay by 30 to 90 minutes using our irrigation sprinklers to melt the frost. We utilize the sprinklers at the links when conditions call for it. Most of the time sprinklers are only effective once the temperature has started to rise following the formation of frost. The morning rise in temperature normally begins 45 minutes after sunrise. If the sprinklers are turned on too early while the temperature was still dropping, the water from the sprinklers would turn into ice delaying the start of play longer than if we let the frost melt naturally.

We push the envelope at the Village Links so our players can tee off as close to on-time as possible but we also need to protect the course from damage so there are good playing conditions the next time you come out to play.

If you want to find out if there is a frost delay on any given day, you can find out by following us on Twitter at
http://twitter.com/GlenEllynTurf
We often "tweet" 30 to 60 minutes before the golf shop opens so you can be alerted to course conditions before you leave home for the golf course.