If you have ever played a late-afternoon round, chances are you have encountered a scruffy or partially collapsed hole. Such a condition is not only unattractive but could also negatively impact playability.
A well-defined hole edge is an important aspect of the game. The Rules of Golf explicitly state that a hole must be 4.25 inches in diameter and at least 4 inches in depth. Maintaining clean hole edges is one of the reasons why holes are changed frequently, often each morning prior to the first tee time. However, there are instances when even a hole that was cut in the morning can become noticeably worn over the course of a day.
The older a given hole location is, the more likely that the edge will become frayed. This makes sense when you consider the number of hands that make incidental contact with the edge when golfers reach down to retrieve their ball. Of course, the amount of damage to the edge increases when an individual tries using a putter to fish their ball out of the hole.
Collapsing hole edges can occur on any type of putting surface but this issue is most problematic with bermudagrass greens. The reason has to do with the horizontal growth habit of bermudagrass. Bermudagrass plants have an extensive network of surface and subsurface stems – known as stolons and rhizomes, respectively – that allow the plant to expand laterally and provide it with structural support. When a new hole is cut, these stems are severed, leaving a percentage of them disconnected from the original plant. A small amount of these loose stems will begin to slough off immediately, while others will be dislodged throughout the day by normal play. Extra care when retrieving one’s ball can help reduce the amount of damage that occurs, but some is to be expected regardless.
Narrow, crescent-shaped tan blemishes might be evident for a few days after a hole is replaced with a new plug of turf until the bermudagrass plants are able to knit together. Cooler temperatures will increase how long the crescent-shaped blemishes are visible because the grass is recovering slowly. Therefore, many golf courses try to reduce the number of times they change hole locations during the winter months.
Another strategy that is common among golf courses with bermudagrass putting greens is the use of a plastic ring near the surface of the hole that helps to retain its integrity. Although the Rules of Golf clearly state that a hole liner – i.e. cup – must be sunk at least 1 inch below the putting surface, they allow for some flexibility if “the nature of the soil requires that it be closer to the surface.” Many golf courses with bermudagrass greens choose to add a separate plastic ring directly above the hole liner in the winter to protect the edges of the hole so that the time between changing holes can be increased.