Creeping Bentgrass Golf Ballmark Recovery as Affected by Various Tools, and Varying Rootzone Surface Firmness and Moisture Content.

Putting green surface smoothness and uniformity is often disrupted by unrepaired ballmarks. Unrepaired ballmarks leave localized necrotic spots, raised locations prone to mower scalping, loss of surface smoothness and potential weed encroachment.  The traditional method for repairing ballmarks employs a metal pronged tool (≈ 2 cm) and a knit and twist method intended to pull healthy turf from the perimeter.  It has been hypothesized that this method may not be the best for repair because the process may severely damage roots. Several new repair tools have been introduced for improved ballmark repair. This field study was conducted in June-July, 2007, on a mature, actively growing bentgrass (Agrostis stolonifera L. cult. ‘Pennlinks’) stand cultivated on a sand-based research putting green in West Lafayette, IN.  Two adjacent study areas were prepared to create “firm” and “soft” study areas.  The firm area was rolled routinely for one week prior to the study and the soft area was not rolled but heavily hand-watered until ponding occurred.  All ballmarks were naturally created by golf balls struck with a pitching wedge from 100 m.  Four ball mark repair tools (Traditional long-tong tool, angled long-tong tool, GreenFix Wizard, standard length wooden golf tee) plus an unrepaired ballmark were randomly assigned to the marks within each location.  Ballmark scars were largest on day 0, with scar areas ranging from to 205 to 640 mm².  Unrepaired scars in the soft area were substantially larger 640 vs. 459 mm² than those in the firm area.  Scar diameter decreased over time and by day 28 all tools resulted in equivalent scar areas.  For both areas the lowest numerical scar area was measured for the GreenFix Wizard, which was not statistically different from the traditional long-tong tool.  One of the worst performing tools in this study was the traditional wooden golf tee.