Light and frequent topdressing is one of the most important programs for producing healthy and smooth putting greens. However, when putting green turf is extremely dense, incorporating sand into the turf canopy can be a difficult task. Sam Sprague, superintendent at Rainier Golf and Country Club in Seattle, shared the two to three week method he uses to successfully topdress greens while minimizing mower damage:
1. The process begins with a light, double verticutting to remove organic matter near the surface and create openings for sand in the dense Poa annua canopy.
2. Sand topdressing is lightly applied along the long length of the green.
3. The sand-covered putting surface is then vented with needle tines or a deep slicing machine. Vibrations from the aerator will incorporate some of the sand into the canopy, provided the sand is dry.
4. The putting surface is brushed with a double, reverse-rotation brush. The first two passes are made around the perimeter to work sand into the collars and cleanup pass.
5. After the perimeter passes, the green is brushed in clockwise circles moving from front to back. If the green is especially large it is brushed in halves. Sprague reports that the first pass leaves windrows of sand at every turn, which is desired.
6. Once the entire green has been brushed in a circular pattern, lengthwise passes are made perpendicular to the windrows. As the brush reaches the end of the green, it is raised, turned counterclockwise, and another lengthwise pass is made. This process is repeated four or five times.
7. Following the lengthwise passes, the green is brushed in counterclockwise circles, working sand into the turf canopy from the opposite direction of the initial clockwise passes. Any sand that remains on the putting surface after counterclockwise brushing is removed.
8. Finally, a backpack blower is used to remove any small amounts of sand that remain.
If you are having difficulty getting topdressing sand to disappear below your bedknives, you may wish to give this method a try. After all, less topdressing sand on the putting surface is a winner for turf, mowers, golfers and especially mechanics.
West Region Agronomists:
Patrick J. Gross, regional director – pgross@usga.org
Larry W. Gilhuly, agronomist – lgilhuly@usga.org
Brian S. Whitlark, agronomist – bwhitlark@usga.org
Blake Meentemeyer, agronomist – bmeentemeyer@usga.org
Information on the USGA’s Course Consulting Service