Principles of Turfgrass Nutrition: why some nutrients are required as fertiliser and others are not

There are 17 essential elements, but not all of those are required as fertilizer. The primary nutrients, macronutrients, secondary nutrients, and micronutrients will be explained, not much in terms of function, but in terms of how the turf manager should think about adjusting their supply. The primary elements are never applied as fertilizer because the grass gets them from air and water. Of the macronutrients, those most often required as fertilizer are nitrogen and potassium. Secondary nutrients and micronutrients are rarely required by the grass, but are sometimes applied to ensure they are present in adequate amounts.

Transcript

1. Principles of Turfgrass Nutrition: why some nutrients are required as fertiliser and others are not Micah Woods January 22, 2018 Chief Scientist Asian Turfgrass Center www.asianturfgrass.com
2. Today’s schedule • 13:30 to 15:00, set 1 • 15:00 to 15:30, coffee break • 15:30 to 17:00, set 2
3. Today’s key points 1. 17 essential elements
4. Today’s key points 1. 17 essential elements 2. Our real objective – good grass
5. Today’s key points 1. 17 essential elements 2. Our real objective – good grass 3. Nutrient deficiencies are avoidable disasters.
6. Today’s key points 1. 17 essential elements 2. Our real objective – good grass 3. Nutrient deficiencies are avoidable disasters. 4. Easy 3 step process to prevent deficiencies
7. 17 essential elements
8. Good grass – what’s it made of? manilagrass, seashore paspalum, and bermudagrass, Thailand
9. 4 classifications of nutrients • Primary nutrients • Macronutrients • Secondary nutrients • Micronutrients
10. 4 classifications of nutrients • Primary nutrients – never required as fertilizer • Macronutrients – often required as fertilizer • Secondary nutrients – sometimes required as fertilizer • Micronutrients – rarely required as fertilizer
11. Primary (or basic) nutrients C Carbon H Hydrogen O Oxygen
12. Macronutrients N Nitrogen K Potassium P Phosphorus
13. Secondary nutrients Ca Calcium Mg Magnesium S Sulfur
14. Micronutrients Fe Iron Mn Manganese Cu Copper Zn Zinc B Boron Mo Molybdenum Cl Chlorine Ni Nickel
15. Our real objective – good grass
16. Has enough nutrients zoysiagrass, Japan
17. Doesn’t have enough nutrients bermudagrass, Vietnam
18. Has enough nutrients zoysiagrass, Japan
19. Doesn’t have enough nutrients zoysiagrass, Japan
20. Has enough nutrients bentgrass and ryegrass, USA
21. Nutrient deficiencies are avoidable disasters
22. Penn A-1 creeping bentgrass, K deficiency
23. I looked through my photo collection to find pictures of other (non-nitrogen) nutrient deficiencies. Then I made this slide.
24. Easy 3 step process to prevent deficiencies
25. Step 1: Healthy grass – and we only care about healthy grass – has a known nutrient concentration.
27. Should we worry about micronutrients? I don’t.
29. Step 2: The amount of nitrogen supplied to the grass controls growth and uptake of the other nutrients
31. “N supply was the primary determinant of turfgrass growth rate, plant nutrient demand, and nutrient uptake. Nitrogen uptake accounted for over 88% of uptake of all other nutrients. Uptake of P and K were strongly related to tissue N content irrespective of soil test levels.” Kussow et al., 2012
32. “The fundamental principle of successful greenkeeping is the recognition of the fact that the finest golfing grasses flourish on poor soil and that more harm is done by over-, rather than underfertilizing.” Alister MacKenzie
33. Old Course at St. Andrews, Scotland
34. Kashima Stadium, Japan
35. manilagrass putting green, Thailand
36. seashore paspalum and bermudagrass, Thailand
37. creeping bentgrass, PGA Catalunya
38. Step 3: Either ensure that soil nutrient levels remain high enough – MLSN works exceptionally well for this – to produce excellent turf conditions, or supply 100% of what the grass uses.
39. For more, please see www.asianturfgrass.com or @asianturfgrass on Twitter.
40. ATC newsletter: www.subscribepage.com/atcupdate MLSN newsletter: www.subscribepage.com/mlsn