1. Does liming affect K fertiliser requirements?

2. Does liming affect K fertiliser requirements?
Does liming increase soil K availability? OR
Does liming reduce soil K availability?

3. Depth (cm) pH Colwell K 0-10 5.2 25 10-20 4.2 15 20-30 17 30-40 4.3
Soil tests
Depth (cm) pH
Colwell K
0-10
5.2 25
10-20
4.2 15
20-30 17
30-40
4.3

4. Trial design 2011 & 2014 2011, 2012, 2013, 2014 & 2016 Lime IBS Banded
2011 & 2014
2011, 2012, 2013, 2014 & 2016
Lime
IBS
Banded
Trt
(t/ha)
(kg/ha) K 1 -
120 Agstar Extra 2
140 K-Till Extra 15 3
60 MoP 30 4
120 MoP 60 5 6 7 8

5. Yield responses
2011
2012

6. Yield responses
2013

7. The value in banding K ….. 3 years on
Photographed 3 July after a dry June (15mm).
Nil K K-Till Extra (15K ) MoP (30K)
Treatments applied in 2011, 2012 and 2013

8. Yield responses
2014
2016
2014 Lime reapplied – another 2 and a half tonnes applied…

9. Liming increased potassium uptake
Lsd lime **
Lsd K
***
Lsd lime x K ns

10. Lime had no effect on Copper or Zinc availability

11. But watch out for manganese

12. No obvious effects of liming on soil K
December 2016

13. Coorow 2013 – lime did not affect K response
Lupins
3.0 t/ha lime applied in 2012

14. Cascade 2016 – lime did not affect K response
2.5 t/ha lime applied in 2013 & 2016

15. Key Messages
Little evidence of lime affecting K requirements in the first few years following application
However, increased production will increase K requirement over the longer term
Have to test the soil (and plants) to ensure we are addressing the most limiting constraint(s).

17. Soil pH
December 2016

18. Bolgart 2016 (35 DAS) MoP (30K) K-Till Extra (15K )
MoP topdressed 12 Apr; sown 17 May.
MoP (30K) K-Till Extra (15K )

19. Bolgart 2016

20. New Norcia 2016 MoP (24K) v K-Till Plus (9K)
K topdressed 12 Apr; sown 16 May after 50mm of rain t/ha v 2.99 t/ha (ns).
Photo 7 weeks after sowing.
Soil K:30K 18K 18K
MoP (24K) v K-Till Plus (9K)
MoP topdressed 5 weeks before seeding

21. Bolgart autumn 2016 Soil Tests Plot Trt Lime K Potassium Colwell
Exc. Potassium 6 1 - 24
0.04 9 15
0.03 21 16 5 4 60 48
0.11 12 63
0.13 22 37
0.07 3 + 20
0.05 19 18 8 54
0.12 13 34 39
0.08

22. Bolgart autumn 2016 Plot Trt Lime K Potassium Colwell Exc. Potassium
Yield (t/ha) 6 1 - 24
0.04
3.08 9 15
0.03
2.98 21 16
3.81 5 4 60 48
0.11
4.37 12 63
0.13
4.02 22 37
0.07
4.80 3 + 20
0.05
4.28 19
4.11 18
4.38 8 54
0.12
5.38 13 34
5.35 39
0.08
5.56

23. NPV after 6 years

24. Adequate nutrition assisting weed control

25. - K
- K
+ K
+ K

26. K responses on high K soils?
Colwell K
Crop
Response?
Mt Ridley 2004
280
Wheat x
York 2014 90
Frankland 2016 94

27. Increased risk of Mn deficiency after liming
Manganese Concentrations

28. Coorow 2013 - lime did not affect K uptake
Potassium Uptake (55 DAS)
Lsd lime ns
Lsd K
***
Lsd lime x K

29. December January February March April Rep 1 65 48 23 30 36 Rep 2 85 44
Williams 2010/2011
December
January
February
March
April
Rep 1 65 48 23 30 36
Rep 2 85 44 37
Rep 3 27 20 24
Average 58 53 22 33

30. Beverley 2016
Costings
K-Till Extra Plus v MAP/MoP

31. Harvest results Treatment Wheat Yield Banded (t/ha) Trt (kg/ha)
Treatment
Wheat Yield
Banded
(t/ha)
Trt
(kg/ha)
Northampton
Arrino
Beverley 1
Agstar Extra
2.38
2.90 a
2.03 2
MAP / MoP
2.44
2.99 a
2.78 3
K-Till Extra Plus
2.45
3.16 b
2.90
Prob
0.18
<0.001
LSD ns
0.13
0.12*
*LSD at 10%

32. Carnamah 2015

33. Lime * P at Bindoon