For golf courses that are open all year long we sometimes run into a drop in the temperature overnight causing frost to form on the fairways and putting greens. Some golf courses choose to continue regular play whereas some courses choose to implement a ‘Frost Delay" or play on Temporary Greens. When the golf course runs a frost delay this normally pushes back all the tee times until the ground has warmed up enough to melt the frost. If frost on the course is ignored and regular play commences it will cause damage to the playing surface and makes the grass susceptible to disease and weeds.
What is Frost?
Frost is frozen dew that crystalizes on the grass, making it hard and brittle to touch. Blades of grass consist of 90 percent water, which is why it freezes so easily. If someone or something was to walk on the frozen grass this would cause the plant to break and the grass cell walls to rupture thereby hindering the grass to grow normally.
Did you know that the average foursome will take approximately 300 steps on each putting green? And with the effects of walking on the grass not being seen immediately the average golfer may not understand the importance of a frost delay. On average the effects of frost damage are not seen until 48 to 72 hours after the membrane damage has occurred, causing the grass to turn brown and die.
Tips on Frost Formation
You may think that it needs to be freezing to create frost; however, this is not the case. Here are a few tips on how and when frost could form.
Frost may occur overnight, but it often occurs at sunrise before the temperature begins to rise. Grass absorbs the sunlight and heat during the day and then loses the heat when the sun goes down. The results of this could cause the temperature of the ground and grass to be cooler than the air temperature
Frost begins to form at 4°C or lower. It does not have to be below freezing for frost for occur
If the sky is clear there is a greater chance for frost. When there is cloud cover this tends to keep the air and ground warmer, almost acting as a blanket.
The USGA has developed a video to explain the causes and effect of walking on frosted greens.