Wednesday, November 15, 2006

Incorporation of sand or inorganic amendments into poorly performing putting greens using deep-tine cultivation practices.

Freddie C. Waltz Jr., The University of Georgia, C&SS - Redding Building, 1109 Experiment Street, Griffin, GA 30223-1797 and Elizabeth Guertal, Auburn Univ.-Agron.& Soils Dep, 202 Funchess Hall, 202 Funchess Hall, Auburn University, AL 36849-5412, United States of America.

The use of inorganic amendments in putting green renovation has become increasingly popular.  Varying widely in composition, the amendments are typically either a silicate clay or a diatomaceous earth, most of which are fired at a high temperature to promote hardness.  Our research objective was to evaluate amendments incorporated into poorly performing putting green root zones, with incorporation via injection into aerification holes.  Two established hybrid bermudagrass (C. dactylon x C. transvaalensis) putting greens located on golf courses were used, one in Griffin, GA, and the other in Auburn, AL.  Amendments were mixed so that they comprised 25 or 50% of each mix, with the remainder sand (v/v).  Amendments were injected either twice (GA) or once (AL) a year in 2004, 2005, and 2006.  One hundred percent sand, aerified-no amendment, and non-aerified contol plots were also included in the studies.  Data collection included quarterly soil tests for nutrients, double-ring infiltrometer readings, laboratory saturated hydraulic conductivity determination, and shoot and root-length measurements.  To date, there have been few measureable improvements in drainage or nutrient holding capacity as affected by the incorporation of various amendments.  Agronomic data (shoot and root) has also not shown a response, with none of the incorporated amendments producing an improved root length or shoot density, as compared to the aerified, sand-incorporated control (AL location).