Assessment of Topdressing Sands and Associated Cultural Practices Used to Manage Ultradwarf Bermudagrass Greens.

Ultradwarf bermudagrasses on golf greens produce a dense canopy that traps some of the sand particles used in topdressing. Larger sand grains appear to be more resistant to falling or being worked through the canopy. Sand trapped in the canopy produces a less desirable playing surface and can be picked up by and damage mowers. Given such, it is becoming common practice to topdress ultradwarf bermudagrass greens with sand having finer particles (i.e. with less fraction of large particles) than those of the sand that the course was originally constructed. Finer sand can produce favorable playing properties of the surface, but they can also produce unfavorable properties with excessive use, such as those problems associated with excess water retention and reduced aeration. To develop recommendations for acceptable properties of topdressing sand, this project seeks to characterize the interaction of physical properties of finer topdressing sand with sand used to backfill after aeration, and the consequential effects on putting green surfaces. A range of golf courses with ultradwarf bermudagrass greens will be identified. For each course, topdressing sand, sand picked up by mowers, and sand used to manage organic matter and to aerate will be examined. Cumulative annual amounts of sands used and geometries of placement will be estimated from measurements and management records. Recommendations for tolerable fineness of topdressing sands will be developed