I always know when a subject is good for a post on my blog. It is generally when a member or golfer ask me a question that is related to turf or an issue we may be having. In today's post the subject was asked by our Club President Grant Faucheux. The question asked was, what are the spots on our greens where it looks like the grass is dying? Very good question but with a pretty long answer. I will try to sum it up in a short version with an added video.
These spots or areas are almost always located over a drain line or on top of a hill or mound crest. It is call localized hot spots and the technical name for the cause is hydrophobicity or hydrophobic for short. A simple way of explaining it is that the sand particles the soil is made up of develops a layer on each grain of sand that is similar to a wax coating and the water just moves right by it. This is important to know because each particle of sand is very rough much like a jagged rock with many points and crevices (you would have to see it under a microscope), it is in these areas that water will attach itself and make it available to the plant root system. If that same rock was made like a bowling ball (smooth) the water would run right off of it and not be available to a plant. Simple enough right, no one said my job was easy did they? In order to combat the hydrophobicity we use chemicals called wetting agents which can break down the wax layer and allow the water to stick to the sand particle. Here is a link to a short video that sorta explains the type of chemicals called wetting agents.