IS3

Location: Coromby


Australian Soil Classification: Calcic, Subnatric, Red SODOSOL

Northcote Factual Key: Dr2.33
Great Soil Group: red-brown earth
Soil Type: Drung Sandy clay Loam


General Description: Eroded crest within a plain.
Geology: Quaternary Woorinen Formation: aeolian dune sand, calcareous clay


Soil Profile Morphology:


Surface Soil

A1	0-5 cm	Brown (7.5YR4/4); sandy clay loam; hardsetting surface condition; weak coarse friable granular structure; pH 7.1; sharp and wavy boundary to:	IS3 Profile
A2j	5–15 cm	Brown (7.5YR4/4) sporadically bleached (10YR7/2d); sandy clay loam; weak coarse friable granular structure; pH 6.2; sharp and wavy boundary to:
Subsoil
B21	15–45 cm	Reddish brown (5YR4/4); light clay; plastic; moderate very coarse prismatic structure; strong consistence dry; slightly sticky consistence wet; very few (<2%) hard carbonate segregations; pH 7.7; clear and smooth boundary to:
B22	45–65 cm	Yellowish brown (10YR5/8); medium clay; plastic; moderate coarse subangular blocky structure; strong consistence dry; sticky consistence wet; very few (<2%) hard carbonate segregations; pH 8.9; sharp and broken boundary to:
B23	65–75 cm	Yellowish brown (10YR5/8); medium clay; plastic; very large lenticular structure (slickensides); strong consistence dry; sticky consistence wet; few (2-10%) soft carbonate segregations; rock fragments; pH 9.0:
C	75+ cm	Impenetrable rock.

Horizon	Sample Depth cm	pH		EC dS/m	Sodium Chloride %	Bulk Density	Exchangeable Calcium cmol-/kg	Exchangeable Magnesium cmol-/kg	Exchangeable Potassium cmol-/kg	Exchangeable Sodium cmol-/kg	Total Nitrogen %	Organic Carbon %	Exchangeable Acidity cmol-/kg	Field Capacity -30okPa	Permanent Wilting Point -1500okPa	Coarse Sand %	Fine Sand %	Silt %	Clay %
		H2O	CaCl2
A1	0–5	7.1	6.4	0.06	0.01	1.47	3.1	0.4	0.6		0.08	1.01	2.9		4.7	45	23	13	14
A2j	5–15	6.2		0.07	0.01	1.54	2.4	0.8	0.4	0.1	0.04	0.54	3.3	13.1	4.8	43	24	15	16
B21	15–45	7.7	6.7	0.3	0.02	1.22	11.8	12	2.5	3.3	0.09	0.58	7.1		30	10	6	3	79
B22	45–65	8.9		0.46	0.02		10.5	12.4	2.2	3.3	0.05	0.27	1.5		24	20	12	6	62
B23	65–75	9.0		0.33	0.02		6.8	9	1.6	2.6	0.03	0.17	1.0		15.9	32	15	8	44

• Strong texture contrasts (16% to 79% clay).
• Neutral upper soil becoming alkaline at depth, high level of nutrients in upper subsoil (B21, B22 horizons).
• Thin surface and subsurface horizon with, poor structure and high coarse sand component.
• Subsurface soil is leached with fewer nutrients than above or below.
• Subsoil is sodic, with sodicity and salinity higher in upper and mid subsoil (B21 and B22 horizons).
• Subsoil is reddish in upper subsoil, indicating relatively free drainage and air movement (oxidising conditions), despite clay percentage.
• Moderate site drainage.