SE Soils A snapshot of some projectsfocusing on acid soils and soil focusing on acid soils and soil modification

Brian Hughes and Mel Fraser, Rural Solutions SA

ContentSoil Acidity in the SE• extent• extent• precision pH testing• acidity and nutrient auditing on SE grazingacidity and nutrient auditing on SE grazing

properties

Soil Modification projects• introduction to New Horizons• improving P retention on leaching soils• demonstration with sub-soiler

Extent of Soil Acidity in the SE

• In acid prone areas, 40% f t il d 50%40% of topsoils and 50% of subsurface layers (10-20cms) < pHCa 5 020cms) < pHCa 5.0

• Should be targeting g gpHCa 5.5 when liming in topsoil and pHca 5.0 in

b fsubsurface

Location of 2009 sites

0-10cm Commercial Soil Test Results

• Sites across all SE soils, 2006-2013, 1048 sitesSites across all SE soils, 2006 2013, 1048 sites

Summary ‐ SE pHCa 0‐10cm soil samplesSource: Back Paddock 2006‐2013

Number of samples

min_pH max_pH % <5.5

Cropping 418 3 62 8 48 22Cropping 418 3.62 8.48 22

Pasture  630 3.8 8.6 33

Rates of Acidification by prone area d i A l A idifi i used to give Annual Acidification target

Mean Annual Acidification RateLand Use

Mean Annual Acidification Rate

Kg lime/ha/y

Low Intensity Grazing 50

Medium Intensity Grazing‐ some hay cuts 100

High Intensity Grazing 150

Cropping Pasture Rotation 100

Intensive Cropping‐ some pasture, high N inputs 200

Continuous Cropping‐ high N inputs 250

Dryland Grazed Lucerne 80Dryland Grazed Lucerne  80

Horticulture‐ high N acidifying forms Up to 500

Lime Use by Acidification in the SE

Why don’t farmers lime more???

• Comments from farmers - snails, difficulty tti li d tgetting lime, need to see a response, over-

liming issues with traces

• Not recommended by some merchants

• Competition for $$Competition for $$

• Need to investigate this issue more!

Any Comments??

Summary SE Soil Acidity• approximately 29% (637,000ha) of the region’s agricultural 

land is susceptible to soil acidity

• in acid prone areas, 40% of topsoils and 50% of subsurface layers (10‐20cms) < pHCa 5.0

• subsurface acidity is a developing issue which is harder to treat than topsoil acidity

l dh ld h i di t d i l fi i l f t• landholders have indicated mainly financial reasons for not liming 

• PA approached to liming treatment may assist with $$PA approached to liming treatment may assist with $$

• soil acidity is treated by other neutralising inputs such as alkaline irrigation water and clay ‐ spreading in the SE

Whole Farm Acidity and Nutrient yAuditing in the SE

Sustainable Dryland Agriculture Initiative St t NRM P 2013 14State NRM Program 2013-14Funded through SENRMB

Brian Hughes and Mel Fraser, Rural Solutions SA

12-13 project highlights

Via the Enhancing Soil Health project developedVia the Enhancing Soil Health project developed • methodology for undertaking whole farm

nutrient and acidity balances on grazing/ y g gmixed properties

• demonstrated this on 3 of the demonstration farms

• highlight areas where data is limited or further g gwork maybe required to improve these models

12-13 project highlights - methodInformation Sourcing• Ag Vic with the dairy industry• Ag Vic with the dairy industry• livestock products. Reuter, D and Judson, G

(www potash info com)(www.potash-info.com)• fertiliser and plant nutrient contents • estimated rates of nitrogen fixation and

leaching• some information on P fixation is available• ball park acidification rates available

12-13 project highlights - methodp j g g

Farmer Survey and Interviewy

Nutrient Balance Calculations

Acidity Balance calculationsd l t f idit diti t l b d• development of an acidity auditing tool based on areas of acid prone soils, lime applied and ball park acidification rates based on land useball park acidification rates based on land use

12-13 project highlights - examples of acidity balance calculationsProperty 1 small grazingProperty 1 – small grazing

P1 Acidity Balance ha AARAcidification 

P1 Acidity Balance ha AARRate t lime

Area Acid Prone 190Moderate Grazing 150 100 15Hay 40 200 8

Total acidification 12‐13 t 23Lime applied 12‐13 t 400Balance  tonnes 377

12-13 project highlights - examples of acidity balance calculationsProperty 3 – mixed cropping/seeds/grazingProperty 3 mixed cropping/seeds/grazing

p3 Acidity Balance ha AARAcidificationRate t limeRate t lime

Area Acid Prone 394Moderate  intensity grazing 214 100 21.4Hay 0 0Hay 0 0Intensively cropped 180 200 36Total acidification 12‐13 t 57.4Lime applied 12‐13 t 156Balance  tonnes 98.6

12-13 project highlights - examples of i b l l l i nutrient balance calculations

Property 2 – mixed cropping/grazingNutrient Removed kgs

P2 Property N P K Mg S CaNutrients OutLivestock Products 16747 2587 1371 156 2333 5348Livestock Products 16747 2587 1371 156 2333 5348leached or fixed 925 12940 175 nd 325 ndHay/ grain sold 64394 6982 14742 2120 3346 1593Total Out 82066 22509 16288 2276 6004 6941

Nutrients InFertiliser/soil amendments 19880 26900 0 0 17550 28500N fixation legumes 31000Ha /grain bro ght inHay/grain brought inTotal in 50880 26900 0 0 17550 28500

P2 BALANCE kgs per farm ‐31186 4391 ‐16288 ‐2276 11546 21559

13-14 Issues identified with 12-13 model• N fixation rates, leaching rates, P fixation are based on 

"Hughes' rough estimates from limited data and investigation Large seasonal differences can occur in all these losses and inputs

• P fixation rates have assumed soil is at reasonable fertility• P fixation rates have assumed soil is at reasonable fertility levels

• no estimates have been made of internal movement of nutrients by livestock to camps, etc 

• nutrient levels for livestock products from limited data and lacking many of the nutrients. Need to discuss with an animal physiologist about this to see what else is available or can use blood, etc,

13-14 project to improve this auditing tool 13-14 project to improve this auditing tool • undertake a desk top study focussed on areas 

where the previous model was deficient 

• collecting more locally based data

• develop these into an improved excel spreadsheet based model 

• undertaken 5 case studies, and 

• present this at the regional NRM/Sustainablepresent this at the regional NRM/Sustainable Agriculture workshop

Precision pH testing p gdemonstrations

SE NRMB – Enhancing Soil Health ProjectAg Bureaus of SA – Innovative Solutions to Ag Bureaus of SA Innovative Solutions to Soil Acidity

Brian Hughes and Mel Fraser, Rural Solutions SA

Precision pH testing - 2 machines being trialed

At Marrabel of Verist d mounted

• only yellow to red needs liming

Saddleworth Comparisonl d d li i (20% f dd k)• only orange to red needs liming (20% of paddock)

12-13 SE project highlightsp j g gVia the SENRMB Enhancing Soil Health project

• trialed the use of a pH precision mapping machine to map the soil pH across paddocksmachine to map the soil pH across paddocks

• demonstrated this on 5 paddocks and trialed/ verified on 2 paddocks in the SEverified on 2 paddocks in the SE

• results were good in one trial and poor in the otherother

Trial Paddocks SE 12-13Trial Paddocks SE 12 13

L dh ld P dd kLandholderName

PaddockName

Area Ha (Est) Soil type

David Paltridge Shed 26 SandDavid Paltridge Shed 26 Sand

Richard Kirkland Ryan’s 45Alkaline clay to SCL/C inplacesplaces

Kirkland’s Comparisoni bl H dd k• variable pH paddock

• machine about 0.5 unit higher

Paltridge Comparisond il • sandy soil

• large difference between lab and machine data

Effect of pH on soil trace element tests

13-14 Issues and directions13 14 Issues and directions• pH machine measure between pHCa and pH w - needs further

correlation• issues with sandy site at Paltridge needs investigation• further investigation/ validation required under different soil types,

moisture content and management practices• to determine the optimum number of samples per hectare to produce

the best mapsthe best maps• has the ability to allow targeted lime applications if confident in the

results• may have the ability to allow targeting of trace elements• more trials planned this year

Sub-soil amelioration trials and demonstrations – 2012/13NR SE – Enhancing Soil Health Project and Mil LelNR SE Enhancing Soil Health Project and Mil LelAgricultural land management project MacKillop Farm Management Group sitesAg Bureaus of SA Lochaber Branch soil health Ag Bureaus of SA – Lochaber Branch soil health project

Mel Fraser and Brian Hughes, Rural Solutions SA

Sites Location Soil Type Treatments Comments

Clothier 1Clothier 2

Woolumbool Deep sand / sand over clay

Subsoiler and spading ‐lucerne straw, 

MFMG

manures, composts

Jaeschke(wheat)

Sherwood Sand over clay Subsoiler and spading ‐lucerne straw, 

tmanures, composts

Lillecrapp(pasture)

Joanna Sand over clay Subsoiler ‐ chickenmanure, gypsum and lucerne pellets

NR SE

uce e pe ets

Schinckel(oats)

Cadgee Shallow Sandy Loam over sodicclay

Subsoiler ‐chicken/sheep manure, gypsum and lucerne

NR SE

pellets

Humphrey Mil Lel Thick sand over clay

Delving and spading and fertiliser

MFMG / NR SE

‘Sub-soiler’

Incorporator type Treatment Yield t/ha

October 2012 November 2013mbo

ol

ControlNo treatment (average of 6 plots)

11.2 8.9

No OM (average of 3 plots) 5.3 7.6

10 t/ha lucerne Silage 5.0 7.5

Pasture ‐W

oolum

Spaded

/ g(average of 2 plots) 20 t/ha Pig Manure 3.6 9.6

20 t/ha Grapemark 5.4 8.7

20 t/ha Sheep Manure 12.2 12.8P / p

Sub‐soiler

No OM 9.2 9.7

20 t/ha Pig Manure 11.9 7.5

20 t/ha Grapemark 10.7 10.0

20 t/ha Sheep Manure 10.6 13.2/ p10 t/ha Gypsum 9.2 9.7

od

ControlNo treatment (average of 3 plots)

‐ 3.1

No OM ‐ 4.1

Grain –Sherwoo

Spaded Hay ‐ 4.2

Grapemark ‐ 3.8

b l

No OM ‐ 3.6

Pig Manure ‐ 4.1Sub ‐ soiler

gGrapemark ‐ 3.7

Gypsum ‐ 3.6

Woolumbool ‐ Spaded treatments

12

14

8

10

d t/ha

6

Pasture yiel

2

4

0Control No OM 10 t/ha lucerne 

Silage20 t/ha Pig Manure

20 t/ha Grapemark

20 t/ha Sheep Manure

2012 2013

Woolumbool ‐ Sub soil treatments

12

14

8

10

t/ha

6

8

Pasture yield t

2

4

P

0

2

Control No OM 20 t/ha Pig Manure 20 t/ha Grapemark 20 t/ha Sheep Manure 10 t/ha Gypsum

2012 2013

4.5

Sherwood ‐ 2012

3.5

4

2.5

3

yield t/ha

1.5

2

Whe

at grain y

0.5

1

W

0

Control Spaded ‐ No OM

Spaded ‐ Hay Spaded ‐Grapemark

SS ‐ No OM  SS ‐ Pig Manure

SS ‐Grapemark

SS ‐ Gypsum

30

Mil Lel ‐ Soil P (Colwell) 0 ‐10 cm

25

20

/kg

10

15

P mg/

5

0

Control Fert Fert + Delve Delve

Treatment

2013 2014

9 0

Mil Lel pasture yield in yr 2

7.0

8.0

9.0

5.0

6.0

ha

3.0

4.0Yield t/

1.0

2.0

0.0

Control Fert Fert + delve Delve

• ‘Spaded’ lucerne hay at Sherwood in wheat: • control 3.1t/ha v’s SLH 4.2t/ha

• ‘Sub – soiler’ treatment of chicken manure at Lillecrapp’s – ryegrass pasture Nov 2013: control 4.1t/ha v’s CM 5.3 t/haLillecrapp s ryegrass pasture Nov 2013: control 4.1t/ha v s CM 5.3 t/ha

Where to from here?

• Continue to monitor the established sites at Clothier’s• Establish a new site at Lochaber on a heavy clay soil

that is acid at the surface and alkaline at depthC ti t k ith A B MFMG NR SE d • Continue to work with Ag Bureau, MFMG, NR SE and others to source funding to extend this work and continue monitoring at established sitescontinue monitoring at established sites

• However, these demonstrations have their limitations and challengesand challenges

• New Horizons…

13-14 Issues and directionsNew Horizons

• pH machine measure between pHCa and pH w‐ needs further

New HorizonspH machine measure between pHCa and pH w needs further correlation

• Issues with sandy site at Paltridge needs investigationF th i ti ti / lid ti i d d diff t il

Releasing the productive potential across 40% of SA

• Further investigation/ validation required under different soil types, moisture content and management practices

• To determine the optimum number of samples per hectare to produce the best maps

• Has the ability to allow targeted lime applications if confident in the results

Mel Fraser and Brian Hughes, Rural Solutions SA

• May have the ability to allow targeting of trace elements• More trials planned this year

Release Productive PotentialRelease Productive PotentialPotential• Overcome soil limitations across 40% of SA cropping• Would achieve $1 billion increase in food production• and 200 M tonnes of CO2e• and reduced long term soil erosion risk

Roadblocks• Proven, consistent methods to address soil constraints profitably

N H iNew Horizons• Science to understand the processes leading to effective soil modification• Trials to understand how to achieve results consistently• Engineering to improve machinery design• Engineering to improve machinery design• Demonstration and extension• Aim for broad‐scale, rapid change in investment and practice

Sub-soil constraintsSub soil constraints

• Poorly structured low fertility sandy soilsPoorly structured, low fertility sandy soils 

• Poorly structured clay sub‐soils 

lk li il• Alkaline soils

• Acid soils

• Boron toxicity

• SalinitySalinity

Sandy soilsy• 2.8 million ha in SA 

• 40% to 50% WUE

• Low technical risk – we know the problem and can• Low technical risk – we know the problem and can demonstrate solutions (albeit not consistently)

P t ti l f d t i ld i f 70%• Potential for crop and pasture yield increases of 70% on average

• Potential for 200 Mt CO2e storage

• Big opportunity is to improve root exploration further down the soil profile and increase pwater use efficiency

Clay mixingClay mixing

• Average 70% yield increases – improved water penetration and root growth and explorationpenetration and root growth and exploration

Deep fertilisationDeep fertilisation

• Average 70% yield increase – improved root growth and exploration

Poorly structured sodic subsoilsPoorly structured sodic subsoils

• 1 7M ha1.7M ha

• We know that gypsum and organic matter can help overcome this issue but how do wehelp overcome this issue, but how do we implement profitably?

E i d h i ld i ld b• Estimated that yield increases would be similar to those demonstrated on sandy soils b d WUEbased on WUE

Road blocks to adoptionRoad blocks to adoption

• Trialability – trials in all key cropping areasTrialability trials in all key cropping areas

• Observability – multiple demos in each area

l i d i k li bili• Relative Advantage – cost + risk vs reliability

• Compatability – engineering + demonstration

• Complexity ‐ demonstration

ADOPT model

Establishment Phase 2014Establishment Phase 2014

• $952,000 in year one$95 ,000 yea o e• Proof of concept

– Show we can double yieldy– Identify the key knowledge gaps for larger program– Build community interest

• Three sites– SE (MacKillop), Mallee (MSF), EP (LEADA)

• Social survey of current practice and what it would take for farmers to change practice

Cadgee Road Site –15 km North of Naracoorte15 km North of Naracoorte

1 clayed + deep nutrition 25 spaded2 clayed + spading + OM + nutrition 26 clayed  + spading + OM3 spaded + OM 27 deep nutrition4 spaded + nutrition 28 clayed + deep nutrition

d d 29 l

Trial Plan

5 spaded 29 control6 control 30 spaded + nutrition7 clayed + spading +nutrition 31 clayed8 clayed + spading 32 clayed + spading +nutrition9 spaded + OM + nutrition 33 spaded + OM10 clayed 34 spaded + OM + nutrition11 deep nutrition 35 clayed + spading + OM + nutrition

Rep 1

Rep 3

12 clayed  + spading + OM 36 clayed + spading13 clayed  + spading + OM 37 spaded + nutrition14 clayed 38 clayed15 spaded + nutrition 39 spaded16 clayed + spading 40 control17 spaded + OM 41 clayed + deep nutrition18 control 42 clayed + spadingp 

2

p 4

Treatments1 control

19 clayed + spading +nutrition 43 clayed + spading + OM + nutrition20 spaded + OM + nutrition 44 spaded + OM21 deep nutrition 45 deep nutrition22 spaded 46 spaded + OM + nutrition23 clayed + spading + OM + nutrition 47 clayed + spading +nutrition24 clayed + deep nutrition 48 clayed  + spading + OM

49 clayed + spading +nutritionRep

Rep

2 clayed + spading + OM + nutrition3 spaded + OM + nutrition4 clayed + spading +nutrition5 clayed  + spading + OM6 clayed + spading 49 clayed + spading +nutrition

50 clayed  + spading + OM51 spaded52 control53 spaded + OM54 clayed + deep nutrition55 clayed56 clayed + spading

Rep 5

6 clayed + spading7 spaded + nutrition8 clayed + deep nutrition9 deep nutrition10 spaded + OM

56 clayed + spading57 spaded + OM + nutrition58 deep nutrition59 spaded + nutrition60 clayed + spading + OM + nutrition

11 spaded12 clayed

Clay application

OM applicationOM application

Spading - incorporationSpading incorporation

• Soil sampling, crop establishment, monitoring

New Horizon Project Collaborators • PIRSA (Trial management and extension)

• University of Adelaide (Soil Science)

• University of SA (Engineering)

• Ag Ex Alliance and Farming Systems Groups (Demonstrations and extension)

• NRM Boards (Communication)

• Private consultants (Extension)

• Private industry (Demonstration)

• GRDC (co‐investment and complementary investment)

• Seeking Federal funding

Over to you…Over to you…

• Questions• Questions• Comments• Ideas for future work?• Got a site we could use?

Thank you