Fundamentals of Turfgrass Maintenance

I spoke at a seminar in Tokyo about the fundamentals of turfgrass maintenance. First I explained how I would define turfgrass maintenance. Then I discussed temperature, leaf nitrogen, plant water status, and photosynthetically active radiation, and explained how these factors influence growth. Temperature data from Tokyo in 2014 and year-to-date in 2015 were used to discuss the influence of temperature on warm and cool season turfgrass growth.

Transcript

1. Fundamentals of Turfgrass Maintenance Micah Woods Chief Scientist Asian Turfgrass Center www.asianturfgrass.com 15 July 2015
2. Today’s topics Four main things 1. My definition of greenkeeping 2. Temperature, nitrogen, water, light: the 4 factors that influence growth 3. Specific challenges for bent and bermuda in Japan 4. US Open discussion
3. Greenkeeping definition At the most basic level, greenkeeping involves controlling the growth rate of the grass.
4. Greenkeeping definition, expanded Greenkeeping involves modifying the growing environment of turfgrass to create the desired playing surface for golf. This involves controlling the growth rate, along with modifications to: ▶ The amount of light reaching the turf
5. Greenkeeping definition, expanded Greenkeeping involves modifying the growing environment of turfgrass to create the desired playing surface for golf. This involves controlling the growth rate, along with modifications to: ▶ The amount of light reaching the turf ▶ The amount of air in the soil
6. Greenkeeping definition, expanded Greenkeeping involves modifying the growing environment of turfgrass to create the desired playing surface for golf. This involves controlling the growth rate, along with modifications to: ▶ The amount of light reaching the turf ▶ The amount of air in the soil ▶ The amount of water in the soil
7. Greenkeeping definition, expanded Greenkeeping involves modifying the growing environment of turfgrass to create the desired playing surface for golf. This involves controlling the growth rate, along with modifications to: ▶ The amount of light reaching the turf ▶ The amount of air in the soil ▶ The amount of water in the soil ▶ The nutrients supplied to the turf
8. Greenkeeping definition, expanded Greenkeeping involves modifying the growing environment of turfgrass to create the desired playing surface for golf. This involves controlling the growth rate, along with modifications to: ▶ The amount of light reaching the turf ▶ The amount of air in the soil ▶ The amount of water in the soil ▶ The nutrients supplied to the turf ▶ Pest control
9. Greenkeeping definition, expanded Greenkeeping involves modifying the growing environment of turfgrass to create the desired playing surface for golf. This involves controlling the growth rate, along with modifications to: ▶ The amount of light reaching the turf ▶ The amount of air in the soil ▶ The amount of water in the soil ▶ The nutrients supplied to the turf ▶ Pest control ▶ Mowing
10. Greenkeeping definition, expanded Greenkeeping involves modifying the growing environment of turfgrass to create the desired playing surface for golf. This involves controlling the growth rate, along with modifications to: ▶ The amount of light reaching the turf ▶ The amount of air in the soil ▶ The amount of water in the soil ▶ The nutrients supplied to the turf ▶ Pest control ▶ Mowing ▶ Surface refinement – rolling, bunker raking, cup cuing, etc
11. Factors that influence growth These are temperature, nitrogen, water, and light. All have the potential to completely stop growth when they are limiting. In practice, temperature is oen the controlling factor.
12. Iceland, May
13. Temperature-based growth potential PACE Turf developed the temperature-based growth potential (GP) to express the actual temperature in terms of its proximity to optimum temperatures for shoot growth. GP = e−0.5(t−to var )2 where, GP = growth potential, on a scale of 0 to 1 e = 2.71828, a mathematical constant t = average temperature for a location, in ℃ to = optimum temperature, 20 for C3 grass, 31 for C4 grass var = adjusts the change in GP as temperature moves away from to ; I suggest 5.5 for C3 and 7 for C4
14. 0 5 10 15 20 25 30 35 2014-01 2014-04 2014-07 2014-10 2015-01 2015-04 2015-07 Date Temperature (ÂřC) Tokyo daily high and low temperature
15. 0 5 10 15 20 25 30 35 2014-01 2014-04 2014-07 2014-10 2015-01 2015-04 2015-07 Date Temperature (ÂřC) Tokyo average temperature
16. 0.00 0.25 0.50 0.75 1.00 2014-01 2014-04 2014-07 2014-10 2015-01 2015-04 2015-07 Date C3 growth potential (GP) Tokyo
17. 0.00 0.25 0.50 0.75 1.00 2014-01 2014-04 2014-07 2014-10 2015-01 2015-04 2015-07 Date C4 growth potential (GP) Tokyo
18. 0 20 40 60 Jan 2014 Apr 2014 Jul 2014 Oct 2014 Jan 2015 Date Cumulative sum of C3 - C4 GP Tokyo 2014
19. 0 20 40 Jan Feb Mar Apr May Jun Jul Date Cumulative sum of C3 - C4 GP Tokyo 2015
20. No fertilizer since 1855, Rothamsted, England
21. Cascade Head prairie, no fertilizer, Oregon
22. 0 10 20 30 40 N K P Ca Mg S Element Amount in bentgrass leaves (g/kg)
23. St. Andrews Old Course, Scotland
24. Kashima Soccer Stadium, Ibaraki
25. 0 5 10 15 20 25 30 35 2014-01 2014-04 2014-07 2014-10 2015-01 2015-04 2015-07 Date Temperature (ÂřC) Tokyo average temperature
26. 0 3 6 9 12 15 18 Jan 2014 Apr 2014 Jul 2014 Oct 2014 Jan 2015 Date Cumulative sum of expected N use (g m-2) Tokyo 2014
27. 0 3 6 9 Jan Feb Mar Apr May Jun Jul Date Cumulative sum of expected N use (g m-2) Tokyo 2015
28. Adjust N supply to get the desired growth rate
29. Plant water status can control growth
30. Hayling, England
31. Measuring soil moisture has become a standard practice
32. 0 250 500 750 Jan Feb Mar Apr May Jun Jul Date Cumulative sum of precipitation (mm) Tokyo 2015
33. Photosynthetically active radiation (PAR)
34. Photosynthetic photon flux density (PPFD), Iceland, May
35. Clouds and PPFD, Saitama, July
36. PAR, PPFD, and DLI What do these mean? ▶ PAR is photsynthetically active radiation. It is the light with wavelengths from 400 to 700 nm. ▶ PAR is measured instantaneously as a flux of photons within those wavelengths on a surface of 1 m2. ▶ Instantaneous PAR is the photosynthetic photon flux density, (PPFD). ▶ Adding together all the PAR from each second of the day gives the daily light integral, DLI.
37. PPFD by hour in 1 day at Ishigaki 0 500 1000 1500 2000 09:00 12:00 15:00 18:00 Time of Day Photosynthetic Irradiance
38. PPFD by hour in 1 month at Ishigaki 0 500 1000 1500 2000 06:00 09:00 12:00 15:00 18:00 Time of Day Photosynthetic Irradiance
39. 0 10 20 30 40 50 60 Jan 2014 Apr 2014 Jul 2014 Oct 2014 Jan 2015 Date Daily light integral (DLI),mol m-2 d-1 Tokyo 2014
40. 0 10 20 30 40 50 60 May Jun Jul Aug Sep Oct Nov Date Daily light integral (DLI),mol m-2 d-1 Tokyo 2014 when mean temperature >= 20
41. Histogram of DLI in Tokyo 2014 when mean temp >= 20 Daily light integral (DLI),mol m-2 d-1 Frequency 10 20 30 40 50 60 0 5 10 15
42. 0 10 20 30 40 50 60 May Jun Jul Aug Sep Oct Nov Date Daily light integral (DLI),mol m-2 d-1 Tokyo 2014 when mean temperature >= 20
43. 0 10 20 30 40 50 60 May Jun Jul Aug Sep Oct Nov Date Daily light integral (DLI),mol m-2 d-1 Tokyo 2014 when mean temperature >= 20
44. 0 5 10 15 20 25 30 35 2014-01 2014-04 2014-07 2014-10 2015-01 2015-04 2015-07 Date Temperature (ÂřC) Tokyo average temperature
45. estions and discussion