MySoil: Deep sandy duplexes (Southern Wheatbelt)

Grey, brown and yellow sands over sandy clay or reticulite (mottled loamy sand) at 30–80 centimetres (cm) depth.

Broad scale map (1:250 000) of the Southern Wheatbelt Agzone showing the distribution of deep sandy duplexes. Distribution is mainly 25–50%, with scattered areas of 10–25% and 3–10% deep sandy duplexes from Cranbrook to Hyden and Hyden to Lake King.
A stylised diagram of the soil profile showing the topsoil and subsoil layers for reticulite deep sandy duplex. The soil profile is grey to yellow sand over (reticulite) mottled loamy sand to sandy clay loam at 30–80cm.
Soil pit showing the profile of reticulite deep sandy duplex in the Southern Wheatbelt region. Grey to yellow sand over mottled loamy subsoil at 80cm.

Summary

Table 1 Deep sandy duplexes summary
Occurrence Southern Wheatbelt (18%)

Soil Groups of Western Australia (WA)

401 Alkaline Grey Deep Sandy Duplex

403 Grey Deep Sandy Duplex

407 Yellow /Brown Deep Sandy Duplex

409 Reticulite Deep Sandy Duplex
Also known as

Blue Mallee soil, Mallee Broombush soil, Mallee soil, WhiteGum soil
Australian soil classifications

Dystrophic Yellow Chromosol

Sodic Eutrophic Brown Chromosol

401, 403, 407 - Calcic Grey, Grey, Yellow or Brown Sodosol, Grey, Yellow or Brown Chromosol

409 - Reticulate Kandosol, Reticulate Chromosol, Tenosol

Distinguishing features

Topsoil

  • Pale brown, yellow or white acidic to neutral sands between depths of 30-80 cm.
  • Gravel (<20%) can be present usually at the base of the topsoil (sand) layer.

Subsoil

  • Bleached sand layer commonly occurs above clay layer.
  • Abrupt boundary between sand and clay layers or mottled reticulite.
  • Clays often sodic, mottled and appear as polyhedral columns.
  • Clay pH mildly acidic to neutral (403, 407, 409) through to alkaline (401).

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 deep sandy duplexes

Soil Groups of WA

401

Alkaline grey deep sandy duplex*

401

Alkaline grey deep sandy duplex*

401

 Alkaline grey deep

sandy duplex*

  

403 Grey deep sandy duplex*

403 Grey deep sandy duplex*

403 Grey deep sandy duplex*

  

407 Yellow /Brown deep sandy duplex*

407 Yellow /Brown deep sandy duplex*

407 Yellow /Brown deep sandy duplex*

  

409 Reticulite deep sandy duplex*

409 Reticulite deep sandy duplex*

409 Reticulite deep sandy duplex*
Constraints

Topsoil (0-10cm)

Subsurface (10cm - clay)

Subsoil (clay)

  

Topsoil (0-10cm)

Subsurface (10cm - clay)

Subsoil (clay)

  

Topsoil (0-10cm)

Subsurface (10cm - clay)

Subsoil (clay)

  

Topsoil (0-10cm)

Subsurface (10cm - clay)

Subsoil (clay)

Acidity and aluminium toxicity

 Minor

Minor

 n/a  

Minor

 Major

n/a

  

Minor

Minor

Minor

   Major

Major

Minor
Salinity n/a n/a Major  

n/a

n/a

 Minor  

n/a

n/a

 Minor  

n/a

n/a

n/a
Sodicity and alkalinity

n/a

n/a

 Minor  

n/a

n/a

 Minor  

n/a

 Minor Major  

n/a

n/a

 Minor
Boron toxicity

n/a

n/a

 Minor  

n/a

n/a

 Minor  

n/a

n/a

n/a

  

n/a

n/a

n/a
Poor nutrient retention

Minor

 Severe

n/a

  

Major

 Severe

n/a

  

Minor

 Minor

n/a

  

Minor

 Minor

n/a
Aggregate stability

n/a

 n/a Minor  

n/a

 n/a Minor  

n/a

 Minor Major  

n/a

 n/a

n/a
Compaction and hard layers

n/a

 n/a Minor  

n/a

 n/a Minor  

n/a

 n/a Minor  

n/a

 n/a Minor
Hard setting and crusting

n/a

 n/a

n/a

  

n/a

 n/a

n/a

  

n/a

 n/a

n/a

  

n/a

 n/a

n/a
Water repellence

Minor

 n/a

n/a

   Major n/a

n/a

   Minor n/a

n/a

   Major n/a

n/a
Low plant available water

Minor

 Major

n/a

  

Minor

 Major

n/a

  

Minor

 Minor

n/a

   Major

Major

 Minor
Water-logging (seasonal) n/a n/a

n/a

  

n/a

 n/a

n/a

  

n/a

 n/a

n/a

  

n/a

 n/a

n/a
Wind erosion (seasonal) Minor n/a

n/a

   Minor n/a

n/a

   Minor n/a

n/a

   Minor n/a

n/a
Water erosion (seasonal)

n/a

 n/a

n/a

  

n/a

 n/a

n/a

  

n/a

 n/a

n/a

  

n/a

 n/a

n/a

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

  • Soil Group of WA - 401 Alkaline grey deep sandy duplex site ID includes: JSI 1038, JSI 1063, COR 0099.
  • Soil Group of WA - 403 Grey deep sandy duplex site ID includes: COR 0091, COR 0093, COR 1773, COR 1637.
  • Soil Group of WA - 407 Yellow/Brown deep sandy duplex site ID includes: JSI 0137, JSI 01444, TBO 0191, COR 0088, COR 0090, COR 1771, COR 1487, COR 1486.
  • Soil Group of WA - 409 Reticulite deep sandy suplex site ID includes: COR 0095.

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 - 9:29am