Doug Karcher Associate Professor Department of Horticulture University of Arkansas

1. Selecting Cultivars Based on Specific Performance CharacteristicsSustainable Turfgrass Management in Asia 2012 Doug KarcherAssociate ProfessorDepartment of HorticultureUniversity of Arkansas karcher@uark.edu turf.uark.edu

4. Tifway hybrid bermudagrass Sod or sprigs

5. Turf-type common bermudagrass, seeded

6. Riviera bermudagrass Seeded

7. Propagation types • Seeded • Zoysia japonica • Vegetative • Zoysia japonica • Zoysia matrella var. matrella

8. Why zoysia seed? Summary of establishment methods and costs for zoysiagrass. 1193K baht/ha 375K baht/ha 225K baht/ha 84K Baht/ha

10. Zoysiagrass establishment rate LSD0.05 = 0.0047 Z. japonica Z. matrella

12. El-Toro Zoysiagras (Z. matrella)Country Club of Little Rock

13. Trinexapac-ethyl PrimoFairway Experiment • Finer, tighter, and more upright for the treated plot

14. Traffic tolerance of various bermudagrass cultivars

15. Sunsport Contessa Veracruz Sovereign Barbados Sultan From: Baldwin, C. M., H. Liu, and L. B. McCarty. 2008. Diversity of 42 bermudagrass cultivars in a reduced light environment. Acta Hort. (ISHS) 783:147-158.

16. ‘Riviera’ bermudagrass

17. Perceptions about bermuda vs. zoysia • Bermudagrass has a faster growth rate • More clippings • More scalping • Faster divot recovery • Zoysiagrass has higher density • Better ball lie

18. Bermuda vs. Zoysia Experiment

19. Bermuda vs. Zoysia Experiment

20. Bermuda vs. Zoysia Experiment • Plots evaluated over 2 growing seasons, once established. • Plots were mown at 1.3 cm (0.5 in). • 40 kg N ha-1 per growing month for bermudagrass and 25 kg N ha-1 for zoysiagrass.

21. Growth Rate (clippings) • Clippings were harvested by making two passes in the opposite direction over the same plot. • Clippings were then collected and oven dried at 80 °C for four days. • Dry weights were recorded to quantify clipping yield.

22. Scalping • Evaluated using digital image analysis • Digital photos taken under controlled lighting conditions and analyzed for % green

23. Digital image analysis used for scalping tendency • Scalping tendency (%): • [100*((percent green turf before mowing - percent green turf after mowing)/percent green turf before mowing)]. Before mowing 99.4% coverage 22.9% Scalping 76.6% coverage After mowing

24. Clipping Yield & Scalping Results • The cultivars with lowest clipping yields were Diamond , Meyer, and Patriot. • Palisades, Princess 77, and Tifway had the highest amount of clippings. • Patriot and Tifsportbermudagrass had the highest scalping across the two years of this study. • All other cultivars had minimal scalping

25. Golf Ball Lie Zorro zoysiagrass Zorro zoysiagrass: 98% ball exposed Palisades zoysiagrass Palisades zoysiagrass: 73% ball exposed

26. Ball Lie Results • When mown, no differences in ball lie. • Palisades zoysiagrass had the poorest ball lie in unmown conditions.

27. Divots ~ 0.2 ha turf removed annually per fairway by divoting.

28. Previous divot recovery research • Bermudagrass (Karcher et al., 2005a) • 2003 results: Riviera, Princess 77, and Patriot > Tifway, Tifsport. • Zoysiagrass (Karcher et al., 2005b) • Palisades, Cavalier, and Zorro had the fastest recovery times. • Meyer consistently had the slowest recovery times. • Although these (Karcher et al., 2005a,b) studies were not performed in the same experiment, they were performed at the same time and location (Fayetteville, AR). • The amount of time required to reach 50% recovery was similar between bermudagrass and zoysiagrass.

29. Our understandings of divoting • Recuperative potential • Divot recovery vs. divot resistance More susceptible to divoting Less susceptible to divoting

30. Materials and methods: divot recovery • Plots were divoted on: • 7 July 2008 • 25 August 2008 • 21 May 2009 • Three (subsamples) standardized divots (5 x 10 cm) were taken from each plot using a modified edger (Fry et al., 2008).

31. Tifwaybermudagrass at day 0 after injury (top) and at day 9 after injury (bottom) Percent recovery was calculated as: 100 * [(%coverx - %cover0) / (100% - %cover0)] day 0 after injury 0% recovery day 9 after injury 72% recovery

32. Divot Evaluations • Severity • 1 = Very small divot, little to no damage • 2 = Small divot, some injury • 3 = Moderate divot size or disruption • 4 = Large divot • 5 = Worst (very large divot) or severe injury

35. Summary – divot recovery • Those cultivars with the fastest time to 50% recovery were • Princess 77 and Riviera bermudagrass • Palisades zoysiagrass • Bermudagrasses recovered faster than zoysiagrasses • Keep in mind, these divots were created mechanically

36. Divot resistancealso differs among cultivars Riviera bermudagrass Diamond zoysiagrass

37. 17 July and 1 September 2009 results – divot severity • Severity

38. Divot Conclusions • Zoysiagrasses tended to have a greater divot resistance. • Z. matrellacultivars (Cavalier, Diamond, and Zorro) consistently had the greatest divot resistance. • Perceived increases in ball lie of zoysiagrass may be a function of greater divot resistance

39. Summary Points • Keep your eye on improved, seeded cultivars • Within species, cultivars vary in establishment, growth rate, traffic tolerance, and divot resistance and recovery • Utilize best adapted species and cultivars to minimize inputs needed to produce quality turf • Current & Future Research • Shade , drought, disease, low management inputs

40. Acknowledgements • Conference organizers • Asian Turfgrass Center • Thai GCSA • The R&A • Dr. Micah Woods