SW111

Location: Mt Gellibrand.

Australian Soil Classification: Vertic (& Calcic), Black DERMOSOL (clayey surface).

General Landscape Description: Flat crest of Mt Gellibrand.
Site Description: Grazing paddock.
Geology: Late Quaternary basaltic scoria.
Soil Type: “Mountain Soil” Leeper et al. (1936)

SW111 Landscape

Soil Profile Morphology:

Surface Soil

A1	0-15 cm	Very dark grey (10YR3/1); medium clay; strong medium to fine polyhedral structure; strong consistence dry; abundant roots; pH 6.4; clear change to:	SW111 Profile
Subsoil
B21	15-30 cm	Black (10YR2/1); heavy clay; strong medium to fine sub-angular blocky structure; strong consistence dry; pH 6.7; clear change to:
B22	30-55 cm	Black (10YR2/1) with few dusky red (2.5YR3/4) and reddish brown (5YR4/3) mottles; heavy clay; strong coarse to medium sub-angular blocky structure; strong consistence dry; slickensides present; shiny faced peds; pH 7.5; clear change to:
B23	55-70/80 cm	Black (10YR2/1) with few brown (7.5YR5/4 and 4/4) mottles; heavy clay; strong coarse to medium sub-angular blocky structure; strong consistence dry; slickensides present; shiny faced peds; includes some weathered scoria; pH 8.8; clear change to:
B24k	70/80-85 cm	Very dark grey (10YR3/1) with brown (7.5YR4/4) mottles; medium clay; many (20%) semi-hard calcareous nodules; abrupt and wavy change to; pH 9:
C1	85-100/105 cm	Mainly (>90%) weathered scoria with narrow bands of structured clay:
2B1	100/105-110 cm	Strong brown (7.5YR5/6); strong medium sub-angular blocky structure; clay; dark stains along ped faces:
2B2k	110-115 cm	Many fine-earth carbonates and structured clay material:
2BC2	115+ cm	Successive layers of scoria with sometimes interceding layers of structured clay material.

Scoria - Vesicular glassy fragments of basaltic composition, partly cemented, generally permeable and readily weathered can be seen exposed in a small excavation west of soil pit.

Key Profile Features:

Gradual increase in clay content in the upper soil profile.
Vertic features i.e. slickensides in subsoil.
Well structured subsoil.

Soil Profile Characteristics:

	pH	Salinity Rating	Sodicity	Dispersion
Surface (A1 horizon)	Slightly Acid	Low	Non-Sodic	None¹
Subsoil (B21 horizon)	Slightly Acid	Very Low	Non-Sodic	Moderate²
Deeper subsoil (at 55-80 cm)	Strongly Alkaline	Low-Medium	Sodic	None³

¹Strong dispersion after remoulding. ²Complete dispersion after remoulding. ²Slight dispersion after remoulding.

Graph: Soil Site SW111

The surface (A) horizon and upper subsoil are slightly acid. The deeper subsoil is strongly alkaline.

The salinity rating is low in the surface. The subsoil is very low becoming moderate at depth.

The surface and upper subsoil is non sodic. The deeper subsoil at 55-80 cm becomes sodic and strongly sodic at 1 m.

The clay percentage is moderate throughout.

Horizon	Horizon Depth (cm)	pH (water)	pH (CaCl₂)	EC dS/m	NaCl %	Total Nitrogen %	Organic Carbon %	Exchangeable Cations
								Ca	Mg	K	Na
								meq/100g
A1	0-15	6.4	5.7	0.16		0.45	5.5	18	14	3	1.4
B21	15-30	6.7	5.8	0.15		0.25	3.1	19	17	2.8	1.9
B22	30-55	7.5	6.6	0.17		0.20	2.5	21	21	2.2	3
B23	55-80	8.8	8.2	0.55	0.04			21	28	1.6	6.1
B24k	100-105	9	8.9	0.86	0.07			18	41	1.4	12

Horizon	Horizon Depth (cm)	Extractable Iron %	Extractable Aluminium %	Exchangeable Aluminium mg/kg	Exchangeable Acidity meq/100g	Field Capacity pF2.5	Wilting Point pF4.2	Coarse Sand (0.2-2.0 mm)	Fine Sand (0.02-0.2 mm)	Silt (0.002-0.02 mm)	Clay (<0.002 mm)


A1	0-15	2.2	0.23	15	16	44.9	33.5	11	11	14	54
B21	15-30	2.3	0.26		15	48.4	35.8	7	10	10	66
B22	30-55	2.3	0.25		11	57.9	37.9	6	10	10	69
B23	55-80					57.9	41.2	4	9	11	63
B24k	100-105							4	12	31	44

Notes: Geology and landform described by Bernie Joyce.

Profile Described By: Mark Imhof, John Martin, Jack Holland and Bernie Joyce (October 2004).

Reference:

Leeper GW, Nicholls A and Wadham SM (1936). Soil and Pasture Studies in the Mount Gellibrand area, Western District of Victoria. Proceedings Royal Society Victoria, 49.

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