Introduction
When turfgrass growth becomes horizontal the leaves begin to lie in various directions. We call this grain. Often times with grain turfgrass leaves are sporadically coarse in nature contributing to a general roughness to the turf. Grain that occurs on putting green is considered negatively in that it impacts putting green consistency. If you are putting with the grain (leaf blades laying away from you) the ball will tend to roll further or be “faster” than if you are putting against the grain (the leaf blades are laying toward you) which will be a much slower putt.
Similarly, golfers may read a putt by looking at which way the grain is laying between the golf ball and the hole. If the grain is toward the golfer the turf may appear a little darker green or conversely if it is laying away from the golfer the turf may be a little lighter color. Grain can impact the amount of break in a putt.
Grain is often associated with the growth habit of the turfgrass species. For example, creeping bentgrass is prostrate in growth while annual bluegrass grows more upright. Bermudagrass greens including the ultradwarf varieties frequently develop grain. Grainy patches develop which is contrasted here between the green areas and lighter green patches. The patches or ares that develop on a bermudagrass green are often described as grain, but the cause may be due in part to genetic mutations.
Mechanical practices to remove grain and improve texture are primarily through mowing practices (frequency, height, direction), verticutting, groomers, brushing, and topdressing. The goal is to get the turfgrass plants to grow vertically or “up-right” thus removing grain and improving density and texture of the turf.
Results
For the last several years we have looked at the impact of brushing, including the evolution in brushing equipment on removing grain and improving putting green turf health. In our field day presentation we will look at relatively low cost methods of brushing. We are studying the impact of the brushing units on plant stress, green speed and overall quality, which is primarily the reduction in grain.