I've had some questions about putting green mower scalping at Timarron CC. Most of it is near the collar of the putting surface. Their are two reason for this 1) unlevel greens/collar transition and 2) encroachment.
1) When there is a slope at the edge of the green, the mower will dig in and scalp. Some greens were constructed with steep slopes near the edges (#17 is the worst), other have become unlevel over time with a build up of either sand topdressing or bunker sand splash. Over the last several years we have been aerifying the collars to help remove this sand build up and smooth out this transition.
2) Encroachment of 419 bermudagrass.
****The collars and the greens are different types of grass. The collars are 419 bermudagrass, which has a coarse, large leaf blade. The greens are Champion bermudagrass, which has a very fine leaf blade.
****We mow the collars and the greens at different mowing heights. Collars are mowed at .500" and greens are mowed at .100"
Overtime the 419 bermudagrass encroaches and grows into the putting green. Because the leaf blade is much larger and the greens are being mowed much lower, the 419 bermudagrass that has encroached into the putting green will scalp.
Unfortunately their is not a good solution for these two issues besides a total renovation of the putting surfaces.
