Reading the Grain of the Green
We often hear TV commentators refer to the impact of the grain direction of the grass on greens. The grain definitely affects the speed of your putt but it appears that greens with Bermuda Bent Grass will affect the direction of your putt more than any other type of grass growing on greens. When you golf in Hawaii or the Caribbean islands and tropical Florida you definitely need to read the Bermuda grass which is used on most of the greens.
The following information came from an article written by Mark Immelman, brother of PGA TOUR professional Trevor Immelman.
Grain Affecting Your Putt (especially on strains of Bermuda Grass):
Grain is the direction that grass grows flat on a green. [Slope of the green (or gravity) has a much greater effect on a putt than the direction of the grain but grain direction will slow down putts when putting into the grain or speed up putts when putting with the grain.] By walking around the putting line of your ball to the hole, you can see lighter green areas where the grain is running away from you and darker areas where the grain in running toward you.
Reading the Grain at the Cup:
The grain of a green has its greatest effect as the ball slows down near the cup. The cut of the grass around the cup will always have a jagged edge on the side where the grain is growing away from the holes. If the clean edge is on the high side of the hole your ball will tend to break into the hole at a faster pace from that side.
Gravity over grain:
Mark Immelman said “I know and trust gravity enough to believe that it will always beat grain when influencing the roll of the ball.” That being said, every so often you may face a putt where the grain is running against the slope of the hill. In that case, play for a little less break than normal, but never aim below the cup and expect the grass to push the ball up the hill. On the flip side, if you happen to face a breaking putt with the grain running in the same direction as the slope, play for more break to allow for the combined efforts of gravity and grain on the rollout of your putt.
Green imperfections caused by golfers using their putter as a crutch near the hole or a poor hole cutting job will always redirect your ball unless you have enough speed at the hole. They are called the “rub of the green”
Strike putts solidly on grainy greens and late in the day when grass on greens will start to lift up toward the sun or rough up with a lot of wear and tear during the day. A mishit putt on bent grass (Bermuda Grass) can still roll out significantly, but a green with coarse, thick grass will normally slow down your putt. Expect speed differences on bent grainy grass from conventional fine grass greens. Learn the green speeds on the practice green before you play a round of golf and practice with GOLFSTR+ to make flat leading wrist putts on your chosen target line. Buy one today at www.GOLFSTR.com
Golf Truism #51: It takes longer to learn to be a good golfer than it does to become a brain surgeon. On the other hand, you don’t get to ride around on a cart, drink beer and eat hotdogs when you are performing brain surgery!
VIEW SOURCE: https://golfstr.com/reading-the-grain-of-the-green/