Frost Delays - What You Need to Know
By Timothy Garceau, Haworth Country Club
Frost delays are difficult to predict in both when they will occur and when they will be over. This can lead to frustration for all involved. By communicating and being prepared with both information and alternatives, stress and aggravation can be minimized.
We know that frost will damage turf when carts, machinery or foot traffic enters the picture. Frost alone is easily tolerated by cool season turf. However, when ice crystals form on the surface of the plant they often form on the inside of the plant as well. This can cause normally resilient turf to become brittle and as turf is crushed from the pressure from walking or equipment, plant cells are punctured and rupture. The damage becomes more severe as the turf mowing height is lowered. Greens are always the most vulnerable both because of the low height of cut and concentration of traffic. When we consider that the average foursome takes about 300 steps per green, it is easy to see how damage can accumulate quickly and become detrimental to turf health. In most cases, turf injury can heal relatively soon, but given the fact that frost occurs typically in months when growth is slower, it can linger for a month or longer.
Predicting frost is far from easy or reliable. At many courses a forecasted low temperature in the area of low 40s coupled with little wind and clear skies bring the potential for frost. Because of where temperatures are recorded, they do not accurately reflect what happens on wide open turf spaces. Temperatures on turf grass areas are quite a bit lower from those in nearby urban areas because turf cools itself throughout the day while man-made or non-living objects absorb heat from the sun. The air above turf areas is much cooler going into the night and cools more rapidly. Additionally, low lying areas and courses located in valleys can be more prone to frost problems as denser cold air will settle and accumulate there. Cloud cover can reduce heat escaping into the atmosphere and often prevent frost from being an issue. Likewise, breezy evenings stir up air so that the cooler air over these large turf areas is mixed with warm surrounding air, keeping temperatures above freezing. A careful look at the weather forecast can tell anyone the likelihood for frost the following morning by observing the wind, cloud cover and learning the temperatures that relate to frost on your course. The fly in the ointment is always the accuracy and foibles of weather forecasts; many times, we can be disappointed when a forecast of 10 to 15 mph winds ends up being a calm evening or some other variable.
What time will the frost be gone? One of the most frustrating questions a superintendent has to answer on a regular basis. We don’t like to guess, we don’t know and we know YOU are waiting. Some overnight frosts are so thick it looks like it has snowed and may never melt, when lo and behold a bank of low level clouds stream in and melt the frost uniformly within 10 minutes. Other frosts can be barely visible and linger well into the late morning. While others can occur right at dawn after the crews have been sent out for work. Frost can be stubborn as well as finicky, but there are signs that superintendents use beyond observation to help assess the length of a frost delay. As a general rule, when we need to rely on the sun alone to melt frost, the delays are the longest. Wind can stir up the air warmed by the sun into stubborn shaded or low lying areas to melt frost more quickly. Low level cloud cover will help reflect heat back to the earth and help to warm things up more quickly than a clear sky. In any case, there are no clear-cut formulas for determining the length of a frost delay.
For superintendents, getting golf underway while preparing the course without injury is the number one goal. We can often direct work to frost-free areas or areas where the frost begins to melt first so that by the time it is safe for golf, very little time is required for final preparations and delays are kept to a minimum. Sunlight is obviously a huge factor in ridding the course of frost, and the topic of sunlight competition from trees is well documented. Shade from trees can not only predispose turf to winter injury in the fall, but it often can lengthen frost delays by preventing sunlight from melting frost. Pruning or removing trees that shade playing surfaces can improve turf health and reduce the duration of frost delays.
Inevitably, many of our challenges in golf can be diminished through better communication. These days there are many avenues for communicating frost warnings or delays to the membership. The golf pro shop is typically informed of frost at first light and sometimes warned the afternoon before of the possibility. Always contact the pro shop if you think there will be a delay. When the frost begins to be a factor, consider an alternative schedule which will help you get in your round without delay.