After getting the basics right - drainage (2-3 main swales), front to back slope for visibility, and maximizing cupping areas with 1.5-3 percent slopes, golf course architects looking to create great greens devote endless hours to adding challenging contours within and on top of those basic parameters. There are many tools we can use. The most often used are briefly described below.
Base Grade Variations. Over 18 greens, randomly varying basic slopes on different greens from 1.5 to 2.5 percent makes green reading more interesting because none break exactly like the last one.
Planed Greens. Because most greens are a mix of swales and ridges, the occasional “tilted plywood sheet” approach provides a unique twist. A constant slope magnifies certain breaks (like downhill trailing putts). These work well on slightly uphill holes, where the constant slope often help attain complete vision of the putting surface that rolls might block. Specific features are listed below.
Long Exterior Ridges. Greens are often shaped within perimeter exterior mounds, which typically extend into the putting surface. Sometimes the mounds “die into” the green edge, but most extend into the putting surface a few feet. Some extend close to halfway across. These create visible, but gentle rolls, partially divides the green into different pin positions, and ties the green and outside contours together with natural flow.
Edge Rolls. Because pins are set back 10-12 feet from the green edge, rolling contours on the green perimeter can give the appearance of rolling contours without greatly reducing cup space or affecting putts. The rolling edge probably makes nearby recovery shots more interesting than they affect actual putts. Depending on their orientation to damaging winter or summer winds, turf type, and green exit traffic, these are subject to drying, and designers consider those factors.
Internal Contours/ Bumps. “Internal contours” are becoming more common. Loosely defined as features contained mostly/entirely inside the green, these are typically small knobs and mounds, because hollows don’t drain. Even on pure sand greens architects are reluctant to design a drainage pocket. These are usually small (from 3-15 inches high).
Subtle Change of Grade. Small, subtle and barely noticeable areas of 3-5 percent slope within areas of primarily 1.5-2 percent slopes increases green reading problems over gently rolling but fairly constant slopes. Breaks encountered midway through a putt’s roll are more unpredictable as to speed, and thus break. Like other features, it’s hard to put pins close to these areas.
Swales. While hollows don’t drain well, sharp feature swales are common. Among the best examples are Charles Blair MacDonald’s famous “Biarritz” holes, featuring deep swales through the green. Modern versions are usually shallower, with gentler side slopes and more free form for a more natural look.
Tiers. Some greens have two to four distinct areas, separated by ridges, swales or 1- to 2-foot-high “stair steps” or tiers. Some are bigger. A few two-tier greens have elevation changes of over 10 feet. The steep slopes of tiers reduce pinnable area. “Wavy” tiers typically create more unusable pockets top and bottom of the tier, and tiers following the long green axis use even more space.
Micro Contours. Older greens are often devilish to read. Their subtlety is probably less a factor of design, and more a result of years of settling and topdressing. With modern bulldozer construction, newer greens may have less future settling.
Practical Considerations. Edge rolls, swales, tiers, ridges and mounds all usually require bigger greens to ensure you get the pin locations you need given your traffic. They are less practical on high play and low budget courses, and are subject to the whims of Mother Nature even on high budget, private courses, as they tend to dry out, especially if there are also environmental, irrigation and/or traffic problems. And, they can scalp, unless there are nice transition slopes at top or bottom.