The problem is, ryegrass is stronger than you may think. Sure, in the middle of the desert it will naturally succumb to high temperatures and fade away, but in San Diego, it will survive year-round even with water cutbacks, high sodium soils, and bermuda competition. We've opted for a very quick transition using herbicides that will wipe the slate clean. No more clumpy ryegrass or Poa annua in the fairways and most of the rough (some cool season grass will remain under trees). Even the kikuyu grass is getting beaten back along with any weeds that came up with the winter rains.
Below is a before/after of some clumpy rye in a hybrid bermuda portion of #15 fairway:
These clumps of ryegrass look insignificant after they are sprayed. There will be no void remaining, like a divot that needs to be filled. The bermuda will fill the space as the ryegrass decomposes. If the whole fairway looked like this, I would have sprayed all of it back on February 2nd. However, the south portion of this fairway is shaded with some trees and hosts a higher population of ryegrass. It will not be spared, but we will wait until we are ready to pull some sod from other areas to replace thin spots. The results shown in this post take a month and the turf is still playable, just off color. We will spray the rest of the fairway soon and map out areas to be sodded. In the photo to the left, our application zone is obvious and you can see the darker ryegrass in the background near the trees. There is plenty of bermuda here as well, but sod will be used in any areas that will not fill in quickly.
This program to eradicate cool season grasses is not limited to the fairways, in fact, this year the main focus will be the rough because the fairways are nearly finished. Below, you can easily see the ryegrass that remains around the green and bunker on #3. I was not comfortable spraying any closer to the green, I wasn't even comfortable spraying this close to the green. I am happy with the results. There was no tracking onto the putting surface and the bermuda under all that rye looks as good as we expected.
These locations were thoroughly mapped out last summer before any cools season grasses could take over. We have already sprayed over 6 acres of rough and will continue through the warmer seasons. A mono stand of bermuda looks so much better than a Heinz 57 mix of grasses. Playability and consistency will improve and summer heat will not be an issue.
Stay tuned for more notes about killing and growing grass. One is nearly as important as the other.
