Pure Stands

Maintaining pure stands of desirable turfgrass on our golf courses is the ultimate agronomic goal. The desirable grass on greens and fairways is creeping bentgrass.  On tees at Stowe Country Club (SCC) the desirable grass is creeping bentgrass. At Stowe Mountain Club (SMC), the tees are a mixture of Kentucky bluegrass and fine fescue. The rough at both golf courses is also the mixture of Kentucky bluegrass and fine fescue. Finally, the desirable grass in the no-mow high grass areas that sit on the edge of golf holes is a blend of fine fescues. At SCC, while creeping bentgrass is most desirable, the fine fescues are considered desirable in all playing surfaces except greens.

The purpose of this goal is based on playability. When multiple different grasses or weeds populate a playing surface ball roll and shot making are both negatively impacted.  On greens, pure stands of creeping bentgrass is desirable because it will provide the smoothest ball roll. The creeping nature of the bentgrasses allows for the ability to mow at low heights of cut. The non desirable grass that we manage against is Poa annua or annual bluegrass. Poa annua is present in the greens at SCC but not at SMC. In the spring, the Poa annua will produce a seedhead which in turn makes for a very bumpy and irregular putting surface. Additionally, Poa annua is not as tolerant to stresses as bentgrass is and will decline in the summer and winter if conditions become severe.

On tees, the two golf courses differ in the desirable grasses but the purity of the turf is still important. Weeds such as crabgrass are kept at bay because of its coarse leaves that produce an uneven surface. Poa annua is considered a weed on both sets of tees because of it's clumpy growth habit. The interesting aspect of our tees is that while creeping bentgrass is the desirable grass at SCC it is considered a non-desirable grass at SMC. The bluegrass/fescue mixture was chosen for tees at SMC due to it's low maintenance costs and durability. Creeping bentgrass has invaded the teeing surface and is now considered a weed on tee surfaces. The bentgrass got into the tees during construction. The bentgrass seed is very small and subsequently was tracked onto the tees from the shoes of the construction workers and was in poorly cleaned drop seeders. As time progressed this aggressive grass has spread. Removal of this grass is needed because the blotchy nature of the bentgrass patches can be distracting to the eye and the feel underfoot is completely different from the bluegrass/fescue mix. Additionally, the agronomic requirements for bentgrass is different than bluegrass/fescue making proper management a challenge.

Pure Creeping Bentgrass #7 Fairway at SMC
On fairways, creeping bentgrass is the best possible playing surface. Kept weed and Poa annua free, a pure bentgrass fairway provides the best possible shot making experience.

In the rough areas, bluegrass/fescue mixtures are the most desirable grass stand because of the upright growth habit. This growth habit props the ball up providing a good lie. Broadleaf and crabgrass weeds can present a problem if the populations are too high causing difficult lies.  As with the tees at SMC, creeping bentgrass is considered a weed in rough areas at both golf courses. The reason for this is that when bentgrass is mowed at rough height of two and a half inches, the bentgrass becomes very puffy. Playing out of a bentgrass rough is difficult because the golf ball settles deep into the puffy bentgrass and the grass will grab the golf club causing errant shots.

In the no-mow areas the fescue grasses are the desirable stand of grass. The fescues have a growth habit that allows for the golf ball to be found and advanced even when the grass is left to grow high and seed out. These fescue areas provide a look to the golf course that is very aesthetically pleasing, especially when the grass turns brown. Weeds and pasture grasses must be kept out of these areas because finding and hitting a ball out of non-pure stands of fescue is very difficult resulting in errant shots and slow play.

The strategy to accomplish the goal of pure stands is varied. When it comes to growing pure creeping bentgrass there are some basic rules. The timing of aerification is very important. Both SCC and SMC greens were both recently aerated because late August and early September is the best time for this. The reason for this is that Poa annua will not germinate when the soil temperatures are warm. Aerating in April and October is avoided due to the cool soil temps and the possibility of increasing the Poa annua populations when the putting surface is opened up due to aeration. The aeration is necessary to maintain proper organic matter and thatch levels. When bentgrass gets too thatchy it can begin to thin and weeds will encroach into the stand. Specific growth regulators are used to promote bentgrass growth and discourage Poa annua growth.

Creeping Bentgrass Turning White On #12 Tees at SMC
Maintaining pure stands of Kentucky bluegrass/fescue is accomplished through the used of different herbicides. The broadleaved and crabgrass weeds can be easily controlled on an annual basis. The more difficult "weed" is creeping bentgrass. The same characteristics that make bentgrass a desirable grass in some areas is the same reason why it is difficult to remove from bluegrass/fescue stands. The aggressive and resilient characteristics of the bentgrass calls for multiple herbicide applications to remove this grass. Currently, at SMC we are in the process of removing the bentgrass from the back nine tees. The product used to remove bentgrass attacks the chlorophyll producing mechanisms of the plant causing it to turn white and eventually starve to death. Ultimately, to maintain a pure bluegrass/ fescue stand we need to produce healthy turf that will crowd out any undesirable weeds.

A Pasture Grass Plant Amongst a Pure Stand of Fescue
It is challenging to maintain pure fescue stands because of the fact we only mow these areas once per year and mowing itself is a method of weed control. The best way to maintain pure fescue is to burn these areas every year. Unfortunately, open field burning is banned in the Stowe, VT area. As a result of not being able to burn we apply herbicides that reduce the weed and pasture grass populations. Often times we will hand pull weeds if the populations are small.

Maintaining pure stands of desirable grasses is our goal. How we get there is multi faceted and often challenging. Once this goal is obtained the playability of the golf courses is improved and the enjoyment of the game is increased.