WARM SEASON GRASSES FOR STATE-OF-ART GOLF GREENS (P1)
The Best Grass for Golf Putting Greens
While many opinions about the cool season and warm season grasses for use on golf putting greens may be found, there is little doubt that the majority of golfers world-wide would prefer to putt on bent grass greens. Bent grass (classified as a cool season species) certainly is the Cadillac of putting green grasses and makes for the smoothest, truest and firmest surfaces. This is especially true with the many new and emerging modern cultivars that have been developed in the last several decades.
It is for these above reasons that most of my previous writings on golf putting green management has focused a good deal on managing bent grass greens. However, there are circumstances and climatic regions where the shear practically of using creeping bent grass becomes formidable.
Grasses are distinguished genetically into two large groups:
- Cool Season
- Warm Season
The growth characteristics of these two groups are obvious from the nomenclature, but the groups coincide into two distinct types of photosynthesis as to their processing of carbon (C). This processing of carbon via photosynthesis light reactions is referred to as the Calvin Cycle as related to carbon dioxide utilization. Without going into a detailed chemistry lesson, cool season grasses are classified as C3 type photosynthesis and have limitations on how much light they can utilize, whereas warm season grasses are classified as C4 type photosynthesis and can utilize light intensity to a linear degree.
Most usually due to the extremes of constant high temperatures, higher humidity / rainfall as well as high intensities and duration of light often encountered in dessert, tropical and equatorial regions, species other than bent grass are often employed for golf putting greens. There are a number of species of warm season, C4 warm season grasses that have been developed for golf putting greens to include cultivars or hybrids of Bermuda grass, Zoysia and Paspalum.
While a few other warm season species are found in use on golf greens around the world, these three species predominate in warm season usage.
The Equatorial Tropics
The equatorial regions of the tropics are increasingly important to the future of the game of golf. Currently about forty percent (40%) of the world’s population lives in these regions and it is estimated that this percentage will increase to around sixty percent (60%) in the next fifty (50) years. Obviously the population shift will also bring changes in golf course management as more golf courses are developed in the tropics. And, of course, hotter climes are not limited to the torrid zones of the equator.
Warm Season Grasses–Management
Generally the development of what I have previously termed the 4Ps of golf greens management evolved toward perfecting consistent creeping bent grass golf greens. Being a seasonal cool season species, bents have a different annual cycle of growth than do the warm season species that are used on greens. However, utilizing the 4Ps on warm season grasses is also highly effective with thoughtful consideration of the seasonal cycle and needs of these species.
The management of warm season grasses on greens should also be systematized into the 4Ps of:
- Rootzone Management
- Surface Management
- Nutrient Management
- Water Management
Furthermore, warm season grass species especially respond best when all cultural practices are employed in light, frequent application methods and regimes, just as with cool season bent.
While there are numerous genus and species of warm season grasses used for turf purposes, primarily hybrid Bermuda grass, Zoysia and Paspalum are commonly used for golf putting surfaces.