In the North-Central Regional Update dated December 16, 2004, Bob Vavrek discusses a common problem that we, as the Green Section staff, are experiencing across the country (http://www.usga.org/turf/regional_updates/regional_reports/northcentral/12-16-2004.html). Bob outlines how a sound topdressing and core cultivation program is the best way to manage organic matter build up.

The evolution of the spin-type topdresser has had a major impact on fine tuning putting green performance. Moreover, without this equipment, it is impossible to manage the newer bentgrasses and bermudagrasses because of their aggressive thatch accumulation tendencies. This equipment allows superintendents to balance sand introduction with thatch accumulation so the mat layer remains porous and open to air and water movement.

Superintendents have experienced a learning curve with topdressing applications. They have found that the light, frequent topdressings should not be as "light" as first thought. Over the past 12 to 18 months, superintendents commonly are increasing application rates by an average of 10% to 15% to better balance the sand:organic matter ratio in the upper profile. The results have improved turf health and performance, especially when a well-planned aerification schedule is blended into the program.

This winter is an excellent time to pull profiles of several greens and carefully weigh the sand:organic matter ratio in the upper 2". An accredited lab can assist with this process by providing physical characteristics of this layer. This in-depth evaluation will provide answers that allow light topdressing rates to be properly gauged to your conditions. You might very well find that a slight increase in the rate is just what you need.

Source: Bud White, budwhite@usga.org or (972) 662-1138.