As we exit the end of the first full week of July 2014 in the aftermath of the “PolarVortex” many winter-survival questions still remain. Here is what we do know… spring green-up was extremely slow and regional weather conditions continue to be suboptimal for aggressive warm-season grass growth. While individual cultural practices for a particular site combined with late-season traffic and macro and micro-environments certainly play a role, one of the overriding major factors affecting survival, however, is plain and simple superior genetics. At this point, we have a pretty good sense for what is persistent in our climate following a severe winter.
The natural question the specialists in our program have often received this spring is: “I lost a significant amount of turf from this past winter. If I replant to bermudagrass, what should I plant that will better survive winter than what we had before?” To help answer that question in 2013 we planted 42 different bermudagrass cultivars as part of the National Turfgrass Evaluation Program trial. Each cultivar was planted in early June of 2013 in a full-sun site and replicated 3 times in our study. By the middle of June 2014 a final “% green bermudagrass” was rated and there were 9 cultivars that had 40% or more green cover (averaged across the three replications). Of these nine cultivars, five are “named”/commercial cultivars (not experimental numbers). These five cultivars were (in no particular order): Yukon, Latitude 36, Patriot, Astro and Quickstand. The remaining four cultivars were “experimental” and are still under long-term evaluation. There is one additional newer cold-hardy cultivar, Northbridge, which has received some attention because of it’s winter tolerance, but was not in our version of the 2013 test. We have since replanted the cultivars that were lost in the 2013 test and this time included Northbridge. In summary… stay tuned for more updates!
For those of you still struggling with your warm-season turf and wondering if you should stick with this grass, please realize the winter of 2013-2014 was one of the most severe in the last 38 years… and is unlikely to happen again this year. Keep in mind, however, that there may be better and improved cultivar “technologies” compared to what you have been managing for decades. Give them a look, even if they are in some small test areas at your facility. And don’t forget… First, THERE IS NO PERFECT GRASS! Second, although the summer of 2012 when we endured severe drought and heat may be a distant memory, summer heat and extended drought will continue to be a chronic concern for decades to come.
Cale A. Bigelow and Aaron Patton – Purdue Turf Science