Turfgrass Winterkill Observations from the Transition Zone

T HE winter of 2013–2014 will be remembered by many turfgrass managers in the transition zone as one of the most severe and devastating in the past two decades. Although we experienced a similar winter in 2000–2001, we have only seen mild examples of winter injury since that period. Extended low temperatures were common throughout the 2013–2014 winter (Fig. 1) and the region experienced several prolonged periods where single digit low temperatures occurred for three or four consecutive days. Although there was variable precipitation throughout the region (Fig. 1), it was not an excessively dry winter, which suggests that most of the injury observed in the region was likely the result of direct low temperature kill rather than desiccation-related problems. he winter injury observed in the transition zone extended from golf courses to athletic ields and home lawns and included damage to bermudagrass (Cyndon spp.), St. Augustinegrass (Stenotaphrum secundatum), and even zoysiagrass (Zoysia spp.). In the research plots at Fayetteville, AR, the principal story regarding survival against low temperature remains improved genetics. he new National Turfgrass Evaluation Program (NTEP) bermudagrass and zoysiagrass trials were planted in Fayetteville in early July 2013 and many cultivars and experimental varieties experienced moderate to signiicant winter injury (Fig. 2). Equally, there were many cultivars that survived the winter without problems. A full reporting of the data from those trials will be available through NTEP in the early part of 2015, but some of the commerciallyavailable bermudagrass cultivars that had the greatest winter survival included Northshore SLT, Latitude 36, Astro, Riviera, and Patriot. In the zoysiagrass trial, cultivars with good survival included Zeon, Empire, Meyer, and Cavalier. As has been documented in the past, warm-season grasses are most susceptible to winter injury in the irst year of planting (Richardson et al., 2004), so some of the injury observed in the research trials may have been partially due to the late plantings in 2013. Published in Applied Turfgrass Science DOI 10.2134/ATS-2014-0049-BR © 2014 American Society of Agronomy and Crop Science Society of America 5585 Guilford Rd., Madison, WI 53711