Anthracnose Disease and Ball Roll Distance Influenced by Light-Weight Rolling and Equipment Traffic.

Anthracnose, caused by Colletotrichum cereale Manns, is a serious disease of annual bluegrass [ABG; Poa annua L. f. reptans (Hausskn) T. Koyama] putting green turf that is influenced by management practices.  Light-weight vibratory rolling, a common practice used to increase ball roll distance (BRD) on golf course putting greens, has been previously shown to reduce anthracnose severity on ABG, but the impact of other roller types or location of equipment traffic on this disease is unknown.  A 3-yr field trial was established in New Brunswick, NJ to evaluate the influence of roller type (i.e., sidewinder, vibratory and non-rolled) and location (center or perimeter) of equipment traffic on anthracnose severity and BRD of ABG turf maintained at 3.2 mm.  The study was established as a strip-plot design with eight replications.  Rolling was performed every other day after daily mowing and all turning of equipment (i.e., mower and roller) occurred in perimeter plots.  In 2007 and 2008, both roller types reduced disease severity 2 to 13% compared to non-rolled turf under moderate disease pressure.  The heavier sidewinder roller had less disease than the vibratory roller on 4 of 13 rating dates throughout the study.  Perimeter plots, which received increased equipment traffic, had less disease compared to center plots on 6 of 13 rating dates during this period.  Both roller types increased BRD and improved turfgrass quality in center plots compared to non-rolled turf.  Results indicate that rolling is an effective practice to increase BRD and improve turf quality without intensifying, and in some cases slightly reducing, anthracnose severity on ABG putting green turf under moderate disease pressure.