Kentucky Bluegrass Response to Wear and Traffic during Autumn.

Tolerance to wear and trampling stresses is important on recreational and sports turf. The objective of this field trial was to evaluate the effects of the Rutgers Wear Simulator (RWS) and the Cady Traffic Simulator (CTS, trampling stress) on entries in the 2011 NTEP Kentucky bluegrass (Poa pratensis L.) trial seeded October 2011 on a loam in North Brunswick, NJ. Three traffic strips (RWS, CTS, and non-treated) were applied using a strip-plot design with three replications across 92 Kentucky bluegrass entries. Twenty-four passes of the RWS and CTS were made from 30 Sep. to 4 Nov. 2015 (4 passes wk^-1 for 6 wk). Uniformity of turf cover was visually assessed and green turf cover was determined by digital image analysis. After 24 passes, green turf cover averaged 93%, 92%, and 58% for the non-treated, CTS and RWS strips, respectively; the uniformity and green turf cover of entries depended on the traffic level. After trampling with the CTS, 79 and 83 entries were in the top statistical group for uniformity and green turf cover, respectively. After RWS treatment, only 12 and 7 entries ranked within the top statistical group for uniformity and green turf cover, respectively. ‘Barvette HGT’, ‘Rubix’, A06-46, SRX 2758, and ‘Nu Chicago’ ranked among entries with both the best uniformity and greatest green cover after RWS traffic. ‘Arrowhead’, SRX 5321, ‘Bewitched’, ‘Midnight’, ‘Bluebank’, J-1853, PST-T10-18, H99-1653 and ‘Aramintha’ were among entries with either the best uniformity or greatest green turf cover after RWS treatment. Thus, Kentucky bluegrass was more tolerant of trampling stress than wear, and wear (RWS) was more effective at distinguishing entries.