In Principles of Golf Course Maintenance with PGA Professional Gary Balliet, we recently discussed the mowing techniques used on tees and greens. That was last week. Today, the conversation shifted to fairways and the rough. This is an excerpt from our PowerPoint lecture.
In the 1950s and the 1960s, fairways were wide open – about 50 yards wide. Now, they’re more like 25 yards wide, and the striping or contouring mowing patterns that are commonplace today didn’t become customary until years later. When fairway cutting units became lighter in the 60s, superintendents got a pleasant surprise during the cutting process. In northern regions where poa annua grass was encroaching into the bentgrass turf, they noticed it becoming less of a problem. That’s because the fairways were being cut with triplex riding mowers, and the grass clippings were being removed.
Because the triplex mowers were more lightweight and because the clippings were being removed, the bentgrass was outgrowing and killing the poa annua turf. The reason: less compaction. Poa annua is one of the few grasses that can survive on tight, compact soils.
Poa annua is both a grass and a weed. Pebble Beach and Torrey Pines in California are both 100% poa. Poa annua (annual bluegrass) is unique because there’s probably no other grass that’s so widely adapted to variations in mowing height, site conditions, and cultural practices.
Another type of poa is called poa trivialis. Often called “winter play,” it’s a newer, darker cultivar more closely complimenting the color of perennial ryegrass and creeping bentgrass when overseeding bermudagrass greens across the southern part of the United States.
Poa trivialis outperformed other commercial, rough-stalk bluegrasses during winter overseeding trials in Scottsdale in the early 90s. Outstanding color, density, and texture give it an edge. After a week or two of summer-like conditions, poa annua greens and fairways start to thin-out and die in small patches. Poa trivialis in the fairways will also start to brown and eventually goes dormant. Both strains of grass like moisture and prefer temperatures around 70 degrees.
On courses in the south that have bermudagrass, newer cutting units, as opposed to the five and seven-gang mowers, make for extraordinary turf because it’s cut to 1/2″ or lower. Lower, more tightly-cut fairways make for more roll. On courses in the north where Kentucky bluegrass, perennial rye, and other fragile grass plant cultivars like bentgrass are more common, the grass must be mowed higher, at 1/2″ or higher.
As a general rule, fairways should rarely be cut to less than 1/2.” The length of the cut is determined by the amount of growth, the weather, the type of turf, and the number of rounds played. As with a putting surface, if the grass is growing faster than the mowers can control it, a retardant like Roundup can be used to slow down the growth of the grass.
Prior to mowing a fairway, any dew should be removed. Heavy dew impedes the quality of the cut and breeds fungus. Heavy rubber hoses or drag mats can be used to remove it, but some superintendents like to turn on the irrigation system to make the water already on the course even wetter. Dew is thick and heavy, and the water acts as a wetting agent. This process also helps with frost delays, provided that the temperature is already above freezing.
The rough is a different story. Rough makes up the largest mowable portion of any traditional, 150-acre golf course and provides an opportunity to frame the course in a natural manner. The rough makes up approximately 60% of that or 80-100 acres. Here’s a more detailed course breakdown:
* Greens = 2-3 acres (2%)
* Tees = 3-4 acres (3%)
* Water = 0-10 acres (0-6.7%)
* Trees = 10-20 acres (10%)
* Fairways = 30-40 acres (23%)
* Rough = 80-100 acres (60%)
I never would have guessed that the grass on greens grew so fast. It almost makes me want to plant that grass in my yard. However, what is really shocking is that round up is used on the grass to make it grow more slowly. How much does it have to be diluted to keep it from just killing the grass?