IS10

Location: Murtoa

Australian Soil Classification: Endocalcareous-Endohypersodic, Self-Mulching, Grey VERTOSOL

Northcote Factual Key: Ug5.24
Great Soil Group: grey clay
Soil Type: Kalkee Clay.

General Landscape Description: Valley flat of a gently undulating plain.
Geology: Quaternary Woorinen Formation: aeolian dune sand, calcareous clay.

IS10 landscape

Soil Profile Morphology:

Surface Soil

A1	0-15 cm	Dark greyish brown (2.5Y4/2); medium clay; cracking and self-mulching surface condition; weak fine subangular blocky structure; weak consistence dry; slightly sticky consistence wet; pH 8.4; sharp boundary to:
Subsoil
B21	15-45 cm	Dark grey (10YR4/1); light medium clay; subplastic; weak fine subangular blocky structure; strong consistence dry; slightly sticky consistence wet; pH 9.0:
B22	45-90 cm	Dark grey (10YR4/1); medium heavy clay; subplastic; weak fine subangular blocky structure; weak consistence dry; slightly sticky consistence wet; very few (<2%) soft carbonate segregations; pH 9.2; gradual boundary to:
B231	90-115 cm	Dark grey (10YR4/1); medium heavy clay; plastic; weak coarse subangular blocky structure; strong consistence dry; slightly sticky consistence wet; very few (<2%) hard carbonate segregations; pH 9.2:
B232	115-125 cm	Dark grey (10YR4/1); medium heavy clay; plastic; weak coarse subangular blocky structure; strong consistence dry; slightly sticky consistence wet; very few (<2%) hard carbonate segregations; pH 9.1; gradual boundary to:
B31	125-150	Greyish brown (2.5YR5/2); light medium clay; plastic; weak subangular blocky structure; strong consistence dry; moderately sticky consistence wet; pH 9.2; gradual boundary to:
B32	150-185	Greyish brown (2.5YR5/2); light medium clay; plastic; weak subangular blocky structure; strong consistence dry; moderately sticky consistence wet; pH 9.0; gradual boundary to:
B33k	185-210	Light grey (2.5Y7/2) with pale brown (10YR6/3) mottles; light clay; plastic; weak subangular blocky structure; strong consistence dry; slightly sticky consistence wet; common (10-20%) soft and hard carbonate segregations; pH 9.2; gradual boundary to:
B34k	210-220	Light grey (2.5Y7/2) with brownish yellow (10YR6/6) mottles; light clay; plastic; moderate coarse subangular blocky structure; strong consistence dry; slightly sticky consistence wet; common (1020%) soft carbonate segregations; pH 9.0.

Chemical and Physical Analysis:

Horizon	Sample Depth cm	pH H₂O	EC dS/m	Sodium Chloride %	Exchangeable Calcium cmol-/kg	Exchangeable Magnesium cmol-/kg	Exchangeable Potassium cmol-/kg	Exchangeable Sodium cmol-/kg	Organic Carbon %	Total Nitrogen %	Permanent Wilting Point -1500^okPa	Coarse Sand %	Fine Sand %	Silt %	Clay %
Horizon	Sample Depth cm	pH H₂O	EC dS/m	Sodium Chloride %	Exchangeable Calcium cmol-/kg	Exchangeable Magnesium cmol-/kg	Exchangeable Potassium cmol-/kg	Exchangeable Sodium cmol-/kg	Organic Carbon %	Total Nitrogen %	Permanent Wilting Point -1500^okPa	Coarse Sand %	Fine Sand %	Silt %	Clay %
A1	0–15	8.4	0.19	0.01	27.4	6.2	3.1	0.3	1.04	0.11	24.4	12	13	8	63
B21	15–45	9.0	0.18	0.02	26.7	8.1	2.0	2.6	0.52	0.06	27.6	10	15	9	65
B22	45–90	9.2	0.48	0.06	19.8	10.6	1.9	7.0	0.24	0.05	29.3	10	14	9	64
B231	90–115	9.2	0.91	0.14	14.3	11.4	2.0	13.1	0.18	0.04	33.5	7	13	9	66
B232	115–125	9.1	1.11	0.17					0.29	0.05		7	13	9	63
B31	125–150	9.2		0.19						0.03		7	11	7	63
B32	150–185	9.0	1.35	0.21							30.5	12	14	8	56
B33k	185–210	9.2	1.31	0.22							28.3	11	12	7	53
B34k	210–220	9.0		0.23							26.0	15	8	9	54

Management Considerations:

Cracking clay profile, high clay percentage but deceases in deep subsoil.
Friable self mulching surface.
Very high calcium percentage in surface and upper and mid subsoil (to 90cm).
Lighter coloured deep subsoil, poorer internal drainage.
Subsoil is strongly sodic and salinity increases at depth, particularly below 90cm.
Poor site drainage.

Profile Described By: John Martin, Nabil Badawy, Ron Cawood, Geoff Pope, John Galea, John Turner (1970).

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