MFS Soils Club - 2017 test results Richard Simpson (CSIRO) Todays - - PowerPoint PPT Presentation

• 1. Highlights from the 2017 soil test results
• 3. Results from this year’s P-response experiments
• 2. Sulphur-management experiments beginning 2018
• 5. Overview of the RnD4Profit: P efficient pastures project

………. and MFS’s role in it

MFS Soils Club - 2017 test results

Richard Simpson (CSIRO)

• 4. New thoughts on soil sampling strategies

Todays agenda:

5 10 15 20 25 30 35 2009 2011 2013 2015 2017 2019

Phosphorus (Colwell) mg/kg

Colwell Phosphorus

Phosphorus (Colwell) Critical Colwell P (estimated)

“Erratic” critical Colwell P estimates

• an artefact created when PBI tests are not done (ignore!)

Highlights from the 2017 soil test results

critical P

Colwell P

Basalts soils: ave = 76 (range: 36-117) Granite soils: = 76 (45-119) Shale/slate soils: = 25 (14-44)

Annual numbers of soil tests “attributed’ to soil type in the MFS soil database:

• There are also many “transition” soils that sit

between basalt and granite or shale soils and, most importantly, many soils with no attributed origin.

• Some effort to record the origin of more of the soils in

the database will improve our ability to probe the data.

• Todays talk focuses mainly on basalt & granite soil results because
• f the strength of the data that is available to us.

(Shale soil results are usually similar in nature to those from the granite soils.)

5 10 15 20 25 30 1 2 3 4 5 6

KCl40 -S

(mg/kg) P fertility index

All data - basalt soils

2010 2011 2012 2013 2014 2015 2016 2017

P deficient S deficient

(2) Critical Colwell P is estimated from the PBI of the soil (1) P fertility index = current Colwell P critical Colwell P

How we interpret the data:

5 10 15 20 25 30 1 2 3 4 5 6

KCl40 -S (mg/kg) P (Colwell) fertility index

All data - basalt soils

2010 2011 2012 2013 2014 2015 2016 2017

0% 20% 40% 60% 80% 100% 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

% deficient pdks

Basalt soils (ave 76 paddocks tested)

P

5 10 15 20 25 30 1 2 3 4 5 6

KCl40 -S (mg/kg) P (Colwell) fertility index

All data - basalt soils

2010 2011 2012 2013 2014 2015 2016 2017

0% 20% 40% 60% 80% 100% 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

% deficient pdks

Basalt soils (ave 76 paddocks tested)

P S

5 10 15 20 25 30 1 2 3 4 5 6

KCl40 -S (mg/kg)

P (Colwell) fertility index

2016 data - Basalt soils

5 10 15 20 25 30 1 2 3 4 5 6

P (Colwell) fertility index

2017 data - Basalt soils Note the dramatic shift in S results between 2016 and 2017:

0% 20% 40% 60% 80% 100% 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

% deficient pdks

Basalt soils (ave 76 paddocks tested)

P S K

0% 20% 40% 60% 80% 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

% deficient pdks

Granite soils (76) 5 10 15 20 25 30 1 2 3

KCl40 -S (mg/kg) P (Colwell) fertility index

All data - granite soils

2010 2011 2012 2013 2014 2015 2016 2017

P

0% 20% 40% 60% 80% 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018

% deficient pdks

Granite soils (76)

P S

5 10 15 20 25 30 1 2 3

KCl40 -S (mg/kg) P (Colwell) fertility index

All data - granite soils

2010 2011 2012 2013 2014 2015 2016 2017

0% 20% 40% 60% 80% 2008 2010 2012 2014 2016 2018

% deficient pdks

Granite soils (76)

P S K

‘Available K’ test in use

(with conversion factor applied)

‘Colwell K’ test

• Similar trends I P and S results to tse for the basalt soils.
• Big change in potassium (K) result associated with a change to the Colwell K test

(With MFS help, we will investigate this further as it does alter perceptions of the incidence of K deficiency.)

2 4 6 8 10 12

1/01/2010 1/01/2011 1/01/201231/12/20121/01/2014 1/01/2015 1/01/2016 1/01/2017 1/01/2018 1/01/2019

Soil test result (mg/kg) "How Good" - granite soil

2 4 6 8 10 12 14

1/01/2010 1/01/2011 1/01/201231/12/20121/01/2014 1/01/2015 1/01/2016 1/01/2017 1/01/2018 1/01/2019

"How Good" - basalt soil

KCl40 -S

2010 2011 2012 2013 2014 2015 2016 2017 2018

KCl40 -S

2010 2011 2012 2013 2014 2015 2016 2017 2018

? ? What has happened to SULPHUR in 2017 ? The options:

(1) Was the lab having a “bad day”?

The ‘control’ soils we resend to the lab every year indicate there was probably a big change in methodology in 2012, but they do not indicate that the 2017 result is due to measurement error.

What has happened to SULPHUR in 2017 ? The options:

(1) The lab was having a “bad day”  (2) There was a lot of S-fertiliser applied on the Monaro in 2017?

• 20
• 10

10 20 30 40 10 20 30 40 Change in S test value (mg/kg)

S applied (kg/ha) Bibbenluke (John Murdoch)

Response of soil test: pre- & post- S application

2015/16 maintenance application = 16 kg S/ha ????

What has happened to SULPHUR in 2017 ? The options:

(1) The lab was having a “bad day”  (2) There was a lot of S-fertiliser applied on the Monaro in 2017?

• 20
• 10

10 20 30 40 10 20 30 40 Change in S test value (mg/kg)

S applied (kg/ha) Bibbenluke (John Murdoch)

Response of soil test: pre- & post- S application

2017 2015/16

What has happened to SULPHUR in 2017 ? The options:

(1) The lab was having a “bad day”  (2) There was a lot of S-fertiliser applied in 2017



(3) Environmental conditions in 2017 have favoured S-mineralisation, conservation and/or retention ?

2010 2011 2012 2013 2014 2015 2016 2017

0% 20% 40% 60% 80% 100% 300 400 500 600 700

% of paddocks that were S-defic’nt

(0-10 cm topsoil)

Total Jan-Aug rainfall (mm, Nimmitabel)

Basalt soils

2010 2011 2012 2013 2014 2015 2016 2017

0% 20% 40% 60% 80% 100% 200 300 400 500 600 700

Total Jan-Aug rainfall (mm, Bombala)

Granite soils

New sulphur management experiments planned for 2018

• 1. Deep soil nutrient profiles will be measured during autumn at 15 sites,

 particularly aiming to determine where S is ending up in soil profiles. (5 sites on each of the basalt, granite and shale-based soils) Granite-based soil

Erosion paddock (1999) (Connemara, via Tarcutta)

• 100
• 90
• 80
• 70
• 60
• 50
• 40
• 30
• 20
• 10

10 20 mg/kg Soil depth (cm)

MCP-sulphur Colwell P

Potassium 0.5 1

meq K/100 g

• 2. Pasture response to S-fertiliser at all 15 nutrient profile sites

 Does the 0-10 cm S soil test adequately indicate S responsiveness?  What value should we place in deep S?

• 3. Soil test response to gypsum at 6 nutrient profile sites

 How much gypsum is required to raise KCl40-S test by 1 unit? … to assist fertiliser rate planning and calculations

Potential experiment sites will initially be identified using the Soils Club database. Nancy will follow up (probably Feb 2018) to ask if people with the right soil types wish to participate. Soil sampling begins AUTUMN, ….after it has rained and the soil is ‘soft’.

Where to next with this study?

Initial results from this year’s P-response expts

5 10 15 20 25 30 35 2009 2010 2011 2012 2013 2014 2015 2016 2017

Phosphorus (Colwell) mg/kg

Figure 1: Colwell Phosphorus, "Ring-a-bells", Quinburra

Critical Colwell P (estimate Phosphoru (Colwell)

2010 2011 2012 2013 2014 2015 2016 2017

100 kg super/ha every year Fertiliser application reverts to 100 kg super/ha 200 kg super/ha CASE STUDY: “Ring-a-bells” paddock, Quinburra (Ron & Mandy Horton)

critical Colwell P Colwell P

100 kg super/ha 200 kg/ha Colwell P mg/kg

Underpinning philosophy:

soil tests should assist pasture management …. NOT ….“stamp collecting”

• Quinburra

PBI = 85 (Ron & Mandy Horton),

• Redcliff PBI = 100

(Ned & Annie Kater),

• Bibbenluke PBI = 200 (John & Kate Murdoch & family)
• Shirley PBI = 330 (John & Sally-Anne Cottle)

Soil test response to P application: 4 sites laid out in autumn 2017 P-fertiliser experiment, Quinburra

Shirley: PBI = 330 y = 0.47x + 108.3 Bibbenluke: PBI = 200 y = 0.33x + 48.9 Red Cliff: PBI = 100 y = 0.31x + 20.8 Quinburra: PBI = 85 y = 0.33x + 28.5 20 40 60 80 100 120 140 160 180 20 40 60 80

Colwell P

(late spring) (mg/kg)

P applied (kg/ha)

Soil test response to P application 2017

3kg P/ha to raise Colwell P by 1 unit

Shirley: PBI = 330 y = 0.47x + 108.3 Bibbenluke: PBI = 200 y = 0.33x + 48.9 Red Cliff: PBI = 100 y = 0.31x + 20.8 Quinburra: PBI = 85 y = 0.33x + 28.5 20 40 60 80 100 120 140 160 180 20 40 60 80

Colwell P

(late spring) (mg/kg)

P applied (kg/ha)

Soil test response to P application 2017

3kg P/ha to raise Colwell P by 1 unit

Table 1. from “Five Easy Steps…….” PBI value of topsoil *EXTRA kg P/ha to raise Colwell by 1 unit

50 200 100 300 2.7 2.9 2.7 3.0 * P in excess of maintenance amount which must also be applied

Back to the case study: 2014: Colwell P = 20 mg/kg, 100 kg super (9 kg P)/ha maintained this critical Colwell P = 32 mg/kg 3 kg P/ha must be applied to raise Colwell P by 1 unit Fertiliser rate was increased to 200 kg super/ha/yr i.e. 9 kg P (maintenance) + 9 kg P for increase Therefore – expected Colwell P to increase by 3 units/yr …..and it should take 4 years to reach critical P.

40 30 20 10

Colwell P

mg/kg

2010 2011 2012 2013 2014 2015 2016 2017 2018

100 100 100 200 200 100 100 kg super/ha critical P Colwell P

expected actual

40 30 20 10

Colwell P

mg/kg

2010 2011 2012 2013 2014 2015 2016 2017 2018

100 100 100 200 200 100 100 kg super/ha critical P Colwell P Conclude: 2 more years at 200 kg super/ha is needed to reach critical P;

then maintenance applics will be a little >100 kg super/ha, because will be running more stock and attempting to maintain a higher Colwell P target level.

40 30 20 10

Colwell P

mg/kg

2010 2011 2012 2013 2014 2015 2016 2017 2018

10 20 30 40

1/01/2010 1/01/2011 1/01/2012 31/12/2012 1/01/2014 1/01/2015 1/01/2016 1/01/2017 1/01/2018 1/01/2019

Soil test result (mg/kg)

"How Good" - granite soil

2010 2011 2012 2013 2014 2015 2016 2017 2018

Colwell P

100 100 100 200 200 100 100 kg super/ha

The difference in soil test P between the expected result and the actual result sits within the ability of the lab to retest an identical sample every year. Scientifically this is called “experimental error”. The “actual result” will also include variability associated with soil sampling (sampling error). So it was most probably just by ‘chance’ that the soil test P results did not reflect the two years of additional P investment during 2014-15.

critical P Colwell P

expected actual

New thoughts on soil sampling strategies

Whole-of-farm soil P testing (53 NSW tablelands farms, 2016)

Source: Jim Virgona (Graminus Consulting)

Deviation from “critical P” (Colwell, mg/kg)

Crit P

Courtesy of Jim Virgona (Graminus Consulting)

P-holiday ? Re-target P for more effective use Opportunity to lift carrying capacity

Courtesy of Jim Virgona (Graminus Consulting)

• 19 paddocks (546 ha); each receiving 125 kg super /ha /year
• ~ 68 tonnes super/year; approx cost spread = $27,200 /year
• Whole of farm soil testing cost: ~ $1,000 - $1,600 /year

15 30 45 60 75 90 105 A B C D E F G H I J K L M N O P Q R S

Colwell P (mg/kg) Paddock ID

Soil P fertility today

Critical Colwell P

Critical+20 Colwell units

OPTION 1 – Apply less fertiliser to high P paddocks

• High-P paddocks receive less P; optimum-P paddocks maintained;

low-P paddocks receive 125 kg super/ha/year over the next 3 years

• Superphosphate use reduced by 16.5 tonnes/year (total saving $19.8K over 3 yrs)

15 30 45 60 75 90 105 A B C D E F G H I J K L M N O P Q R S

Colwell P (mg/kg)

Paddock ID

3-years later

Soil test P at initial survey OPTION 1: Business as usual OPTION 2: "Europen vacation" OPTION 3: Re-targeted P use

Soil test P levels at initial survey OPTION 1: “European vacation”

OPTION 2 – Re-targeted use of P fertiliser

• High P paddocks receive less P; optimum P paddocks maintained;

low P paddocks receive more super/ha each year over the next 3 years

• No extra cost  increased potential carrying capacity

15 30 45 60 75 90 105 A B C D E F G H I J K L M N O P Q R S

Colwell P (mg/kg)

Paddock ID

3-years later

Soil test P at initial survey OPTION 1: Business as usual OPTION 2: "Europen vacation" OPTION 3: Re-targeted P use

Soil test P levels at initial survey OPTION 2: Re-targeted use of P

1 2 3 4 5 6

5 10

P- fertility index Farm Whole-of-farm P testing (2017)

F MP K M

Data from the 2017 MFS soil testing dataset

1 2 3 4 5 6

5 10

P- fertility index Farm

Whole-of-farm P testing (2017)

F MP K M 10 20 30 40 50 60 70 80

5 10

KCl40

• S

Farm

Whole-of-farm S testing (2017)

F MP K M

?

1 2 3 4 5 6

5 10

P- fertility index Farm

Whole-of-farm P testing (2017)

F MP K M 5 10 15 20 25 30 35

5 10

KCl40

• S

Farm

Whole-of-farm S testing (2017)

F MP K M

‘Grid-testing’ for zonal fertiliser management of paddocks

Delegate Station Grid Soil Maps (2016): Rob Sth Paddock (32.4 ha)

Source: John Jeffreys, Delegate Station

pH CEC Lime recommendation Ca Mg Potassium (K)

Cost: $17-20+ /ha i.e. this test in this paddock: $640

• 8 soil cores combined for a single soil test per 2 ha grid
• compromises on soil test precision (importance??);

some “replication” as a result of the grid sampling

• some mapping “licence” is taken due to large grid size

Potassium fertility map

Potassium fertility map

Available K soil test based on transect = 156 mg/kg; CONCLUDE - not K deficient Map-based available K soil test CONCLUDE: (1) 37% of paddock is K-deficient (2) Estd cost to production = ~20% (3) K-fertiliser to be applied to the RED & PURPLE zones only

100 200 300 400 500 600 700

1/01/20101/01/20111/01/2012 31/12/2012 1/01/20141/01/20151/01/20161/01/20171/01/20181/01/2019

Soil test result

(mg/kg)

"How Good" - granite soil

2010 2011 2012 2013 2014 2015 2016 2017 2018

100 200 300 400 500 600 700

1/01/20101/01/20111/01/2012 31/12/2012 1/01/20141/01/20151/01/20161/01/20171/01/20181/01/2019

"How Good" - basalt soil

Available K Available K

2010 2011 2012 2013 2014 2015 2016 2017 2018

Colwell K Colwell K

Another potential issue?:

We need another “How Good” control soil  one more suitable for checking K-test proficiency?

yellow serradella

subterranean clover

0 5 9 21 41 75

P applied (mg/pot)

0 5 9 21 41 75

RnD4P Project: P-efficient pastures

Monaro sites: Red Cliff (via Bombala) & Glen Finnan (via Cooma)

1 2 3 4 20 40 60 80

yellow serradella French serradella subterranean clover biserrula rose clover

Shoot dry weight (g/pot) P applied (mg/pot) yellow serradella French serradella subterranean clover

2,000 4,000 6,000 8,000 10,000 12,000 20 40 60 80 100

Rate of P application (kg/ha) Herbage yield (spring harvest)

Burrinjuck 2013

2000 4000 6000

sub clover French serradella yellow serradella

20 40 60 80

(kg DM/ha)

French serradella yellow serradella sub clover Burrinjuck 2014 French serradella yellow serradella sub clover

2 1 0 100 200

Western Australia (Bolland and Paynter 1992) yellow serradella subterranean clover

P applied (kg/ha) Herbage yield (t DM/ha)

95% max grth

Yellow serradella

Ornithopus compressis

Subterranean clover

Trifolium subterraneum

Important things we don’t know yet !

• Except in a few districts…

serradella yield, persistence, disease susceptibility in permanent pastures is unknown.

• serradella adaptation range & persistence

across variable paddock landscapes is untested.

current project

is addressing these issues

Project - main themes

Serradella systems

• Very P efficient (~30% less P fertiliser?)
• Yield & adaptation to HRZ unknown
• Insufficient persistence suspected

(relative to sub clover) P-efficient sub.clover systems

• Very well adapted to HRZ
• Low P efficiency (cf serradella)

Development of productive HRZ pasture system system(s) that require substantially less P fertiliser than is presently needed

Focus (areas where serradella is not used): Yield & persistence in HRZ pastures Focus (areas where serradella is used): Proof that less P fertiliser can be used Focus: Identifying the most P-effic. cultivars Focus: Can we develop sub.clovers with “serradella-like” root systems?

THANKYOU

All welcome at the Farm Walk to inspect the serradella plots

• n ‘Red Cliff’

20 December 2017

National

‘P-efficient pastures’

project team:

Richard Simpson, Graeme Sandral, Richard Hayes, Suzanne Boschma, Megan Ryan, John Howieson, Tim McLaren, Ron Smernik, Mike McLaughlin, Therese McBeath, Hans Lambers, Chris Guppy, Alan Richardson

Acknowledgements:

Current research funded by: Dept of Agriculture and Water Resources

(Rural R&D for Profit program)

Meat and Livestock Australia,

Dairy Australia

Australian Wool Innovation Ltd, & collaborating research and farmer organisations.

The University

• f Adelaide