Wednesday, November 7, 2007
268-26

Low Impact Conversion of Cool-Season Turf to 'Patriot' Bermudagrass.

James M. Goatley Jr.1, Shawn D. Askew2, and Kevin Hensler1. (1) Crop and Soil Environmental Sciences, Virginia Tech, 424 Smyth Hall, Blacksburg, VA 24061, (2) Plant Pathology, Physiology, and Weed Science, Virginia Tech, 203 PMB Glade Road Research Center, Blacksburg, VA 24061

High quality bermudagrasses with improved cold tolerance are replacing traditional cool-season turfs for golf and sports turf uses in the transition zone of the United States. However, renovation programs to convert from cool-season to bermudagrass turf can prevent site use for up to 10 weeks. This research was conducted to evaluate pre-plant cool-season turf control treatments as they affect the establishment of row-planted ‘Patriot' bermudagrass. Four pre-plant treatments (an untreated check, strip-kill vegetation control with glyphosate using 5-cm bands on 15-cm centers, total vegetation control with glyphosate, and trinexapac-ethyl) were applied to mixed stand cool-season turfgrasses at the Turfgrass Research Center in Blacksburg, VA and Bridgewater College in Bridgewater, VA approximately 10 days prior to row-planting Patriot bermudagrass at 430 stems per sq meter on 29 May 2006. Following intensive irrigation for 2 weeks after planting (WAP), clipping height and summer fertility programs that promoted bermudagrass development were employed. Total vegetation kill resulted in 100% Patriot coverage by 10 WAP at both sites, but visual turf quality ratings were unacceptable through 6 WAP. The strip-kill treatment resulted in ≥ 80% total ground cover ratings by 6 WAP and ≥ 75% Patriot coverage by 10 WAP at both locations. However, orientation when rating the plots was an important consideration because the ratings were deemed acceptable at 6 WAP when viewing the plots perpendicular to the spray band. Primo Maxx and the untreated control provided ≥ 90% vegetation coverage at any time during the trials. These treatments achieved 70 to 80% Patriot coverage by 10 WAP, indicating the possibility that the playing surface might only need to be completely removed from use for a 2 week initial sprig establishment period.