Definition: 'Collar' on a Golf Green
We sometimes hear golfers (or golf commentators) refer to the collar of a putting green. What is the collar? It is a ring of turfgrass around some greens that is slightly higher the grass of the putting green itself.
"Collar" is a synonym of "fringe" (and its slang term, "frog hair"). Sometimes it is used interchangeably with "apron," but apron more specifically refers to the area in front of a putting green where the fairway transitions into the green.
The height of the grass in the collar is typically around the mid-point between the height of the green and the height of the fairway grasses. The collar can be thought of as a transition between putting green turf and any rough around the green, or even as a buffer between the green and any rough.
But take note that not every putting green has a collar. A collar might also be enountered ringing a bunker, but they are far less common around bunkers.
A golf ball that comes to rest on the collar of a putting green is considered off the green and cannot be lifted without penalty. For the purposes of statistical tracking, a ball struck from the collar is not considered a putt by the professional tours, even if a putter was used for the stroke.
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