There is a common misperception that putting greens gain speed throughout the day. Anyone who watches televised golf regularly is familiar with comments about greens speeding up as the day goes on and surfaces become drier. While putting greens will certainly become firmer throughout the day if they are not irrigated, most of the time their speeds do not increase.
Collecting green speed data at USGA championships is a responsibility of USGA agronomists. This data is used to monitor trends throughout the day and work with the host course superintendent to determine which combination of surface management practices needs to be performed to achieve the desired playing conditions. Results from years of data collection consistently show that green speeds slow down throughout the day. An exception is when widespread moisture stress exists and irrigation is not performed. As the grass wilts, green speed can increase because there is less resistance on a ball rolling across the surface – but this scenario should be avoided due to the potentially negative impact on turf health.
Putting green speeds decrease throughout the day because the turf is growing. Ideally, the agronomic program is designed so that turf is growing enough to recover from environmental stress, golfer traffic and maintenance traffic, but not so much that growth is excessive. By managing fertilizer inputs and plant growth regulator applications, the growth rate can be managed to minimize how much speed is lost throughout the day.
How much the turf grows will vary throughout the year and depends on the weather. We are seeing more superintendents incorporating growth potential in their agronomic programs to better predict growth and make adjustments as needed. The “Turf GvX” approach is a related concept that combines growth potential and clipping yield data.
While there are other equally (if not more) important putting green performance metrics beyond green speed, it is not likely that golfers and television commentators will lose their fascination with this metric. No matter what they might claim, the reality is that healthy putting greens slow down as the day progresses.
Central Region Agronomists:
Zach Nicoludis, regional director, Central Region – znicoludis@usga.org
Tom Gould, agronomist – tgould@usga.org
Information on the USGA’s Course Consulting Service
Contact the Green Section Staff