COURSE CARE

USGA Putting Green Construction Resources October 15, 2021 By USGA Green Section

Since 1960, the USGA has published recommendations for a method of putting green construction. These recommendations have been successfully used by thousands of golf courses around the world. To ensure their integrity, the recommendations are regularly reviewed by scientists, industry experts and USGA Agronomists. The latest science-proven technologies and techniques are added with each new revision. 

Once the architect marks off the shape and contours of the new putting green, the construction process begins. Builders use a variety of heavy equipment to construct putting greens, relying on skilled operators to carefully follow the architect’s design. Specialized surveying equipment and digital mapping technology helps builders implement the putting green design with precision and efficiency. 

Proper construction of the subgrade is critical to the success of a USGA putting green. The subgrade should be shaped to match the general slope of the finished grade and must be smooth and firm, with no water-holding depressions. Often, shaping the subgrade is the most difficult part of putting green construction because the soils may be very difficult to grade smoothly.

Subsurface drainage systems quickly remove excess water from putting greens. Place main drain pipes along the lines of maximum fall. Extend lateral drain pipes, spaced not more than 15 feet apart, to the putting green perimeter. All drain pipes should have a minimum continuous slope of 0.5 percent. Install perimeter drains immediately adjacent the cavity wall in low-lying areas.

The gravel layer in a USGA putting green allows the rapid movement of excess water out of the rootzone mix and into the drainage pipes. The gravel layer must be installed to a minimum depth of 4 inches, but the depth can vary above that to create the desired contours. The final surface of the gravel layer must conform to the proposed finished grade of the putting green.

In rare cases, an intermediate layer is needed to prevent the rootzone mix from migrating into the gravel layer. This situation can be avoided by selecting properly-sized gravel in relation to the rootzone mix. The proper gravel size can only be determined by laboratory testing. If an intermediate layer is needed, it should be spread to a consistent depth of 2-4 inches.

Rootzone blending can occur at the production facility or at the golf course, the best choice for each project depends on various factors. Regardless of where the mix is blended, a homogenous mixture must be achieved for success. Mechanical blending equipment must be used, and appropriate quality control procedures should be followed throughout the project to ensure consistency.

The rootzone mix is installed to a uniform depth of 12 inches, plus or minus 1 inch. Heavy equipment is used to spread and compact the mixture, ensuring a firm, smooth surface. Builders probe the rootzone mix throughout installation to ensure a consistent depth. The final firming and smoothing is accomplished with smaller equipment and careful raking.

Before establishing turf on a new putting green, the irrigation system must be installed and properly adjusted. Once the irrigation system is fully operational, and after the final floating, turfgrass can be planted. Key considerations during establishment are early disease control, frequent and light fertilization, and allowing young turfgrass time to mature before it is subjected to the stresses of play.

The USGA would like to thank the following for their help during the production of this video series.