WARM-SEASON In spring/summer 2013, new trials of

bermudagrass and zoysiagrass were established, with 35 entries in each trial. In addition, a unique new trial was established in conjunction with the United States Golf Association (USGA). Te trial evaluates bermudagrass (15 entries), zoysiagrass (11 entries) and seashore paspalum (2 entries) at eleven locations under putting green conditions. Te third year of data from each of these

three warm-season trials is now available from NTEP. Even though each trial features a different set of data, a common theme of all these trials is data on initial establishment from 2013. However, due to the unusually harsh winter that many locations experienced in 2013/2014, several entries were never able to establish at some locations. Data on winter injury was collected and the cooperators were consulted on the condition of their trials. Since 2013-14 was the worst winter in more than thirty years, the decision was made by NTEP to replant several or all entries at the worst winter injury sites. NTEP has never replanted so many entries and locations in our history, but we felt it was necessary to give all entries an equal opportunity to establish and perform. No more replanting will take place for these three trials. Te information on the entries replanted at each location is noted on the data tables.

Bermudagrass Te new bermuda NTEP trial contains eighteen

(18) seeded entries and seventeen (17) vegetative entries. Many of these entries are experimental cultivars or new commercial cultivars. NTEP evaluates warm-season grasses by comparing seeded and vegetative entries, and also by separately comparing seeded vs. seeded and vegetative vs. vegetative. After the 2014 replanting, we are now past the

establishment phase and have data that more reflects long-term performance. In that regard, we have ratings that show the potential of new experimental entries. In 2016, entries such as TifTuf, OKC 1131, OKC 1163, 11-T-510, JSC-2-21-1-v and JSC-2-21-18-v, all vegetative entries, performed very well finishing in the top statistical group at many locations. Tis performance compared favorably, or surpassed in some cases, previous top performers Latitude 36 and Tifway. It remains to be seen if any of these entries will eventually replace Tifway, arguably the most widely utilized turf bermudagrass in history. And as in the past, the seeded entries were often

outperformed by the best vegetative entries. However, at Jay, FL, Tucson, AZ and Lexington, KY, the seeded

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entries 12-TSB-1 and MSB 002 continued to perform well, and similar to the top vegetative entries. Additional entries, such as Princess 77, BAR C291 and JSC-2007- 13-S, have performed well at times, being statistically equal to the best vegetative entries at a few locations. Tis trial will collect its final year of data in 2017, and that will help us to determine if these new seeded experimentals can match the quality and performance of the vegetative bermudas. Several ancillary trial locations again conducted

unique tests in 2016. Some results were not significant, as in most of the nematode counts made in Gainesville, FL. Traffic tolerance differences were noted at Lexington, KY, with TifTuf, JSC-2-21-1-v, OKC 1131 and OKC 1302 topping the traffic ratings. Tese results were not seen under the traffic stress imposed on the Knoxville, TN trial, as little statistical differences among entries were noted. And in dollar spot ratings collected at Raleigh, NC, Tifway, OKC 1302, PST-R6CT and 11- T-510 showed the highest tolerance ratings. Since water use reduction is probably the

most important issue the turf industry is facing, our drought ancillary trial conducted at College Station, TX is immensely important. Performance differences evaluating drought tolerance were significant in 2016, as they were in 2015. In that trial, TifTuf and OKC 1163 were statistically superior to almost every other entry, where turf quality scores in 2016 ranged from 8.0 to 4.8 (LSD=0.4).

Zoysiagrass Meyer zoysiagrass was released in the early

1950’s and has been a standard in the industry ever since. Meyer is known for its medium leaf texture (for a zoysia japonica type) and excellent winter hardiness. Zeon is a zoysia matrella type that is finer textured than Meyer. Zeon is a standard for use on golf course fairways and tees because it can develop a dense turf at mowing heights of 0.5” or lower. Both grasses are included in this new trial as standard entries. One of the weaknesses of zoysiagrass is its rate of

establishment, especially compared to other warm-season species. Terefore, plant breeders are working to improve spread and recovery rate in zoysiagrass. For both of these traits, it appears that breeders are making considerable gains. In addition, Meyer historically has not performed particularly well in the warmer southeast and southwest locations, therefore zoysia cultivars that perform well in those regions are much needed. As with the bermuda trial, injury in the winters

of 2013-14 and 2014-15 significantly affected some locations. Winter injury was evident at Manhattan, KS, West Lafayette, IN and Columbia, MO with turfgrass quality and percent cover ratings being affected by that injury. Meyer and KSUZ 1201 suffered only a small amount of winter kill at those locations (only 1.3 and

TPI Turf News July/August 2017