MySoil: Clays and shallow loamy duplexes (Southern Wheatbelt)

Grey red or brown loam over clay subsoils at <30 centimetres (cm). Grey and red non cracking clays.

Broad scale map (1:250 000) of the Southern Wheatbelt Agzone showing the distribution of clays and shallow loamy duplexes. Distribution is scattered with 25–50% near Cranbrook to Katanning while near Corrigin and Wickepin is 10–25%.
A stylised diagram of the soil profile showing the topsoil and subsoil layers for grey non-cracking clay (soil group 621). The soil profile is grey non-cracking clay thoughout.
Soil pit showing the profile of grey non-cracking clay in the Southern Wheatbelt region. The soil profile is grey clay thoughout.

Summary

Table 1 Clays and shallow loamy duplexes summary
Occurrence Southern Wheatbelt (13%)

Soil Groups of Western Australia (WA)

504 Grey shallow loamy duplex (Grey clay)

508 Yellow/Brown shallow loamy duplex (Moort soils)

621 Grey non-cracking clay

622 Red/brown non-cracking clay
Also known as

Grey and yellow clays, Moort soils, Hardsetting grey clays

Australian soil classifications

504 Grey or Yellow Chromosol, Grey or Yellow Sodosol

508 Yellow or Brown Chromosol, Yellow or Brown Sodosol

621 Grey or Yellow Dermosol, Grey or Yellow Kandosol

622 Red or Brown Dermosol, Red or Brown Kandosol

Distinguishing features

Topsoil

  • Surface soils are hard loams (504, 508) and clays (621, 622).

Subsoil

  • Dense poorly drained loamy to light clay subsoils.
  • Subsoils can range from mildly acidic to highly alkaline with carbonate at depth.
  • Saline and sodic subsoils common.

Constraints

The following data has been derived from actual site samples taken. These results are recorded in this Excel spreadsheet.

Table 2 Common management constraints key
Rating Implications
Not applicable (n/a)

No constraints identified
Minor

Minor constraint - reduces crop yields in some years
Major

Major constraint - reduces crop yields in most years
Severe

Severe constraint - will always reduce crop yields
Table 3 Management constraints for clays and shallow loamy duplexes

Soil Groups of WA

504 Grey shallow loamy duplex*

504 Grey shallow loamy duplex*

507 Red

508 Yellow

/Brown shallow loamy duplex*

507 Red

508 Yellow

/Brown shallow loamy duplex*

621 Hard grey clay

622 Hard Red/Brown clay*

621 Hard grey clay

622 Hard Red/Brown clay*
Constraints Topsoil Subsoil Topsoil Subsoil Topsoil Subsoil
Acidity and aluminium toxicity n/a

n/a

n/a

n/a

n/a

n/a
Salinity

n/a

 Minor

n/a

 Minor

n/a

 Major
Sodicity and alkalinity

n/a

 Minor

n/a

 Major

n/a

 Major
Boron toxicity

n/a

n/a

n/a

n/a

n/a

n/a
Poor nutrient retention

n/a

n/a

n/a

n/a

n/a

n/a
Aggregate stability

n/a

 Minor

n/a

 Major

n/a

 Minor
Compaction and hard layers

n/a

n/a

n/a

n/a

n/a

n/a
Hard setting and crusting Minor

n/a

 Minor

n/a

 Major

n/a
Water repellence

n/a

n/a

n/a

n/a

n/a

n/a
Low plant available water

n/a

n/a

 Minor Minor Minor Minor
Water-logging (seasonal)

n/a

n/a

n/a

n/a

n/a

n/a
Wind erosion (seasonal)

n/a

n/a

n/a

n/a

n/a

n/a
Water erosion (seasonal)

n/a

n/a

n/a

n/a

n/a

n/a

*Note - Data derived from site identifications (ID's).

  • Soil Group of WA - 504 Grey shallow loamy duplex site ID includes: KLC 0159, COR 1785.
  • Soil Group of WA - 507 Red shallow loamy duplex site ID includes: COR 1776, COR 2001.
  • Soil Group of WA - 508 Yellow/Brown shallow loamy duplex site ID includes: COR 1772, COR 0025, TBO 0173, TBO 1388.
  • Soil Group of WA - 621 Hard Grey Clay site ID includes: COR 0062, NYA 0648.
  • Soil Group of WA - 622 Hard Red/Brown Clay site ID includes: NYA 0727, TBO 0562.

Further information

Department of Agriculture and Food (2013) Report card on sustainable natural resource use in agriculture, Department of Agriculture and Food, Western Australia.

McArthur, WM (2004) Reference Soils of South-western Australia (Reprint). Department of Agriculture, Western Australia.

Moore, G (2004) Soil Guide: A Handbook for Understanding and Managing Agricultural Soils. Bulletin 4343. Department of Agriculture, Western Australia.

Overheu, TD (1995) Soil Information Sheets for Ravensthorpe and part of the Jerramungup Agricultural Areas. Department of Agriculture, Western Australia and Landcare Western Australia.

Percy, H (2003) Nyabing-Kukerin Area Land Resource Survey. Land Resources Series No. 18. Department of Agriculture, Western Australia.

Sawkins, D (2010) Landscapes and Soils of the Katanning District. Bulletin 4817. Department of Agriculture and Food, Western Australia.

Sawkins, D (2011) Landscapes and Soils of the Lake Grace. Bulletin 4825. Department of Agriculture and Food, Western Australia.

Stoneman, TC (1990) An Introduction to the Soils of the Lake Grace Advisory District. Bulletin 4178. Western Australian Department of Agriculture.

Stoneman, TC (1991) An Introduction to the Soils of the Narrogin Advisory District. Bulletin 4221. Western Australian Department of Agriculture.

Stoneman, TC (1991) An Introduction to the Soils of the Katanning Advisory District. Bulletin 4202.  Western Australian Department of Agriculture.

Schoknecht, N and Pathan, S (2013) Soil Groups of Western Australia. Resource Management Technical Report 380. Department of Agriculture and Food, Western Australia.

Stuart-Street, A (2005) Tonebridge-Frankland Area Land Resource Survey. Land Resources Series No. 19. Department of Agriculture, Western Australia.

Verboom, B and Galloway, P (2004) Corrigin Area Land Resource Survey. Land Resources Series No. 20. Department of Agriculture, Western Australia.

See also

MySoil

Further information

Soils

Topics

Page last updated: Wednesday, 18 November 2015 - 9:30am