Investigation of Soil Amendments for Use in USGA Putting Greens

1. Investigation of Soil Amendments for Use in USGA Putting Greens T.W. Shaddox

2. Problem Assessment • Droughts from 1997 to 2000 have brought about consumptive use permits for many superintendents • Superintendents have less water to maintain the same quality turfgrass

3. Case Study • Colbert Hills GC – Manhattan, KS (Fry, 2002) • 120 million gallons year-1 = 374 acre feet • 374 / 365 days ≈ 1 acre foot day-1 • 1 acre foot / 150 acres = 0.08 inches day-1 !!

4. Problem Assessment • Greens receive 2-3 X more N than Fairways • Greens typically receive daily irrigation • Low nutrient retention in sand-based greens • 27% of applied P may leach (Shuman, 2001) • 56% of applied N may leach (Snyder, 1984)

5. Literature Review

7. Surfactant • HDTMA CH3(CH2)15N(CH3)3

8. 26-28 Å Sorption Process

9. Objective:To determine the influence of soil amendments and incorporation method on water use efficiency (WUE) of Tifdwarf bermudagrass Ho: Soil amendments and incorporation method do not increase Tifdwarf WUE above sand:peat

10. Objective:To determine the influence of surfactant-modified amendments (SMSAs) on N and P leaching in a simulated USGA putting green Ho: SMSAs do not reduce N and P leaching in USGA putting greens

11. Materials and Methods Water Use

12. Methods • All pots in each study were maintained at 90% pot capacity • Sprigged with Tifdwarf • Pots were havested and weighed weekly for 18 weeks • WUE = dry matter / applied water • Turf Quality taken weekly (1 to 9) • 10 trts 4 reps RCBD • Duncans MRT α = 0.05

13. Treatments

14. Incorporation Method Mixed Profile (85:15) • Aerification (50:50) • 9 Cores • 4 Cores Sand + Amendment Sand + Peat

16. Materials and Methods N and P leaching

17. PUMP H2O 30 cm 5 cm 2.54 cm Materials and Methods • Columns • Pb = 1.5 g cm-3 • pH = 7.1 • Injection Solution • pH = 2.5 • NO3-N = 2300 ppm • NH4-N = 2480 ppm • P = 4400 ppm • 10 mL Pump H2O 30 cm Sand/Peat Treatment Layer 5 cm 2.5 cm

18. Materials and Methods • Treatments: • Sand • Sand/Peat • Ecosand • Soil Master • Profile • HDTMA Ecosand • HDTMA Soil Master • HDTMA Profile • Treatment = 8 • Rep = 3 • Duncans MRT α = 0.05

19. SMSA Characteristics

20. Results Water Use

21. Rootzone Chemical and Physical Characteristics

22. ANOVA Turf Quality

23. Turf Quality Full Incorporation a minimum acceptable quality b b c c c c d d e CV = 4.3

24. Turf Quality 9 Tine Aerification minimum acceptable quality a b bc bc cd de de de ef f CV = 1.9

25. Turf Quality 4 Tine Aerification minimum acceptable quality a b bc bc bcd d d cd d d CV = 1.8

26. ANOVA Turf WUE

27. WUE Full Incorporation a a ab ab b b c c d d CV = 6.8

28. WUE 9 Tine Aerification a b bc bc bc bc bc bc c c CV = 8.3

29. WUE 4 Tine Aerification a b b b b b b b b b CV = 9.2

30. WUE by Incorporation Method CV = 3.5

31. WUE Summary • Only CCs and Fe Humate increased turf quality • Individually, PAW and CEC are not good indicators of an amendment’s influence on WUE • Fe Humate, CCs, and diatomaceous earths increased WUE above peat • Fe Humate produced the greatest increase in WUE • Amendment influence was decreased after aerification

32. WUE Conclusion • WUE • Reject Ho and conclude: • Calcined clays, Diat. Earths, smectite, and Fe Humate increased Tifdwarf WUE above sand:peat • Quality • Reject Ho and conclude: • Calcined clays and Fe Humate increased Tifdwarf quality above sand:peat

33. Practical Implications • When WUE and turf quality are of concern, calcined clays and fe humate are plausible options to peat

34. Results N and P Leaching

35. NO3--N Breakthrough Curves Sand Sand/Peat HDTMA-Soil Master AEC = 11.3 Soil Master HDTMA-Profile AEC = 9.7 Profile HDTMA-Clinoptilolite AEC = 4.1 Clinoptilolite

36. Total NO3-N Leached CV = 9.8 Columns with same letter are not significantly different according to DMRT > 0.05

37. NH4+-N Breakthrough Curves Sand Sand/Peat HDTMA-Soil Master AEC = 11.3 Soil Master HDTMA-Profile AEC = 9.7 Profile HDTMA-Clinoptilolite AEC = 4.1 Clinoptilolite

38. Total NH4-N Leached CV = 12.9 Columns with same letter are not significantly different according to DMRT > 0.05

39. P Breakthrough Curves Sand Sand/Peat HDTMA-Soil Master AEC = 11.3 Soil Master HDTMA-Profile AEC = 9.7 Profile HDTMA-Clinoptilolite AEC = 4.1 Clinoptilolite

40. Total Phosphorous Leached CV = 6.9 Columns with same letter are not significantly different according to DMRT > 0.05

41. Leaching Summary • Uncoated amendments: • did not retard or decrease NO3- leaching • eliminated NH4+ leaching • retarded but did not decrease P leaching. • SMSAs reduced NO3-, NH4+, and P leaching

42. Leaching Conclusion • Reject Ho and conclude: • SMSAs reduce N and P leaching

43. Future Research • Long-term influence on leaching and stability • Microbial degradation • Influence on turf growth

44. Acknowledgments • Committee • Jerry Sartain (Chair) • Donald Graetz • Peter Nkedi-Kizza • James Bonczek • Grady Miller • SWSD Grad Students • E. Brown, R. Snyder, K. Makris • Lab Personnel • Ed Hopwood, Nahid Varshovi, Shawron Weingarten, Brian Owens, Martin Sandquist • Florida Turfgrass Association

45. Questions