MySoil: Deep loamy duplexes and earths (Mullewa to Morawa)

Brown or Red loams grading to clay.

Broad scale map (1:250 000) of the Mullewa to Morawa Agzone showing the distribution of deep loamy duplexes and earths. The majority of the Agzone has 10–25% deep loam duplexes and earths. There are areas with 3–10% near Mullewa and from Wubin to Morawa.
A stylised diagram of the soil profile showing the topsoil and subsoil layers for deep loamy duplexes and earths. Red loam throughout or may grade to clay.
Soil pit showing the profile of red loamy earth in the Mullewa to Morawa region.

Summary

Table 1 Deep loamy duplexes and earths summary
Occurrence

Mullewa to Morawa (15%)

Soil Groups of Western Australia (WA)

505 Brown deep loamy duplex

506 Red deep loamy duplex (York Gum soil)

541 Brown loamy earth

544 Red loamy earth (Red loam)
Also known as

York Gum soil, Red loam
Australian soil classifications

Mesotrophic Red or Brown Kandosol, Mesotrophic Red or Brown Dermosol

505, 506 – Yellow, Brown or Red Chromosol, Yellow, Brown or Red Sodosol

541, 543, 544, 545 – Brown, Red or Yellow Kandosol, Brown or Red Dermosol, Red or Brown Ferrosol

Distinguishing features

Topsoil

Red or brown hard-setting loam.
Acid to neutral pH.

Subsoil

  • Neutral (505,506,541) to alkaline (542) pH.
  • Loams (505,506) grading to clays (541, 542).
  • Calcareous nodules (506, 542) or Ironstone gravels may be present (541).

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 loamy duplexes and earths

Soil Group of WA

541 Brown loamy earth*

541 Brown loamy earth*

544 Red loamy earth*

544 Red loamy earth*
Constraints Topsoil Subsoil Topsoil Subsoil
Acidity and aluminium toxicity Minor Minor n/a

n/a
Salinity n/a Minor

n/a

n/a
Sodicity and alkalinity

n/a

 Minor

n/a

 Minor
Boron toxicity

n/a

n/a

n/a

n/a
Poor nutrient retention

n/a

n/a

n/a

n/a
Aggregate stability

n/a

 Minor

n/a

 Minor
Compaction and hard layers

Minor

Minor

Minor

Minor
Hard setting and crusting Minor

n/a

 Minor

n/a
Water repellence

n/a

n/a

n/a

n/a
Low plant available water

n/a

 Minor

n/a

n/a
Water-logging (seasonal)

n/a

Minor

n/a

Minor
Wind erosion (seasonal)

n/a

n/a

n/a

n/a
Water erosion (seasonal)

Minor

n/a

Minor

n/a

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

  • Soil Group of WA - 541 Brown loamy earth site ID includes: TSL 0321, GTN 1416.
  • Soil Group of WA - 544 Red loamy earth site ID includes: GTN 2002, GTN 1407.

Further information

Agriculture Western Australia (1997) Soil Information Sheets for the Northern Agricultural Areas. Miscellaneous Publication 13/97. Agriculture Western Australia.

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.

Rogers, LG (1996) Geraldton Region Land Resource Survey. Land Resources Series No. 13. Agriculture Western Australia.

Stoneman, TC (1990) An Introduction to the Soils of the Geraldton Advisory District. Bulletin 4181. 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.

See also

MySoil

Further information

Soils

Topics

Page last updated: Wednesday, 18 November 2015 - 9:17am