Reducing Ultradwarf Bermudagrass Putting Green Winter Injury with Covers and Wetting Agents.

Core Ideas: All cover treatments reduced winter injury of bermudagrass compared to the uncovered control.‘TifEagle’ and ‘MiniVerde’ cultivars experienced less winter injury than ‘Champion’.A late‐fall wetting agent can reduce winter injury on bermudagrass putting greens.Reducing the predicted low‐temperature threshold for placing covers had no negative impact on survival. As ultradwarf bermudagrass (Cynodon dactylon [L.] Pers. × C. transvaalensis Burtt‐Davy) is used on putting greens in more northern locations, there is increased risk of sustaining winter injury from desiccation and low‐temperature exposure. During the winter, installation and removal of protective covers can be costly and labor intensive. This research aims to define a predicted low‐temperature threshold when covering an ultradwarf bermudagrass putting green becomes necessary, and to quantify the effects of a late‐fall wetting agent application on winter survival of ultradwarf bermudagrass. Research was conducted over three winters (2015–2018) in Fayetteville, AR on a sand‐based putting green established to ‘Champion’, ‘MiniVerde’, and ‘TifEagle’ bermudagrass cultivars. Covering treatments were placed on the green at forecasted low‐temperature thresholds of 15, 18, 22, and 25 °F and were compared with an uncovered control. A single late‐fall wetting agent application was applied to each cultivar × cover treatment. The wetting agent occasionally enhanced spring green‐up, but this effect was inconsistent across seasons. Winter injury to the cultivar ‘Champion’ was greater than ‘TifEagle’ and ‘MiniVerde’. Plots receiving cover treatments, regardless of covering temperature, achieved faster spring green‐up than the uncovered control. Differences in green turf coverage between cover treatments were detected; although, those differences were not considered to be of practical importance. Therefore, it is possible to reduce the predicted low‐temperature threshold for covering greens without a significant increase in winter injury, resulting in reduced golf course labor costs and increased potential revenue with more days open for play. [ABSTRACT FROM AUTHOR]