Summer Weed Control
Weed cleanup on golf courses is continually a work-in-progress. It is especially a problem on golf courses that were previously overseeded. When courses are overseeded, pre-emerging for weeds can be very difficult since pre-emergents keep not only weeds from germinating but grass seed as well. So often, pre-emergents are not applied at all. This proposes a major problem for golf courses in future years and that is what we are now dealing with.
I am relatively certain that most of you remember how “weedy” BVCC was last summer. The crabgrass was out of control on many holes. We decided this spring to switch herbicides for our spring pre-emergent to a chemical that would better keep the crabgrass from germinating and encroaching our fairways. The good news is, our plan has worked so far. There are very few crabgrass plants on the course where we sprayed our pre-emergent. There are, of course, crabgrass plants that are in areas where we did not pre-emerge. On the other side of the cart path, opposite the fairway, are good examples of where we do not pre-emerge. We do not typically pre-emerge these areas as we try to spend most of our chemical budget on areas that are played more often (around greens, tees, and fairways).
The bad news about our change in pre-emergent herbicides, is that while the crabgrass is under control, the goose grass has gotten a little out of control in some areas. Did you know that a single goose grass plant can produce 50,000 seeds!? When a plant produces that many seeds, it can be very difficult to control once it is established. Therefore, as turf managers when we see goose grass we will make every attempt to kill it before it spreads, particularly to greens. We have made some attempts to kill the goose grass without discoloring the Bermuda, but so far, the goose grass has refused to die.
In recent years, the EPA has outlawed many herbicides, most notably is Illoxan which was the best goose grass herbicide on the market. Since we are “handcuffed”, so to speak, on what we can spray to kill the goose grass, we are forced to take measures that will discolor Bermuda grass. You will notice several areas around BVCC that will be an unsightly yellow or brown color. This happens when we spray the goose grass that is intermingled within the Bermuda grass. This chemical will only kill the goosegrass. Although it may appear that the Bermuda grass is dying, rest assured, the chemical only discolors the Bermuda temporarily.
As turf managers, we are continually striving to provide better playing conditions. Unfortunately, at times we must take a step back (discolor Bermuda) to take two steps forward (kill the weeds). This is part of the process to clean up the course so that our pre-emergent herbicides will work better for us in the future. We thank you for understanding and hope that you continue to enjoy your rounds even if every blade of grass is not always green!
Rob Dreesen
Golf Course Superintendent
Bella Vista Country Club