Friday, August 7, 2009

Bermuda Encroachment

In this photo, Richard Rivera is using a Mataway seeder to verticut the 1/2 inch collar and cut some of the bermudagrass stolons. Over the next 3 months, we will perform this practice regularly in an effort to damage the common bermudagrass and discourage its movement into the greens. In mid-late September, we will also use some chemical applications to kill the bermuda that is actively growing inside the green.

Our two-collar system is designed as a buffer between the bentgrass greens and the common bermudagrass that makes up our green surrounds. Unfortunately, it is very difficult to reason with bermuda that is enjoying a triple digit heat wave. Our previous efforts have led us back to the drawing board more than once and we are still experimenting with a useful solution. There is little you can do in the middle of summer because bermuda is bulletproof when it gets this hot. However, as cool temperatures approach, the bermuda begins to store reserves for the winter and becomes susceptible to damage. Chemical sprays and invasive practices, like verticutting, will weaken the plant, making it less likely to survive the winter months. When the heat returns, the bermuda does not. This sounds very similar to overseeding in the fall. All of the bermuda is weakened and some of it will not be alive in the spring. That is the price you pay when you want green fairways for a few months in the winter, but more on that later.

As we work on decreasing the bermuda population on the collars, we will also seed in our desired grasses. The inner 1/4" collar will be seeded with Alpha bentgrass and the 1/2", outer collar will be seeded with perennial rye. We will repeat this process frequently until we have a very dense and uniform stand of turf. Next spring, we will evaluate the results of this program and adjust accordingly.