ALRA067

Colluvial fan leading to Mount William Creek		Site Code	ALRA067
		Location	Moyston West Road
		Landform	Gently undulating plain
		Geology	Quaternary alluvium
		Element	Plain
		Slope	1%
		Aspect	South
Horizon	Depth (cm)
A1	0–5	Dark greyish brown (7.5YR3/1); coarse sand; massive (structureless); very weak consistence when moderately moist; pH 6.5; clear and smooth boundary to:		Eutrophic, Mottled-Subnatric, Grey SODOSOL
A21	5–30	Light grey (10YR7/2); sporadically bleached (7.5YR6/3 dry); loamy sand; massive structure(structureless); very weak consistence when dry; pH 6.5; clear and wavy boundary to:
A22	30–45	Pinkish grey (7.5YR7/2); sporadically bleached (7.5YR7/3 dry); loamy sand; massive (structureless); weak consistence when moderately moist; pH 6.5; gradual and wavy boundary to:
A23	45–60	White (10YR8/2) with few coarse faint brownish yellow mottles; sporadically bleached (10YR7/3 dry); clay loam; massive (structureless); weak consistence when dry; pH 5.5; sharp and wavy boundary to:
B21	60–75	Greyish brown (10YR5/2) with many medium to coarse distinct brownish yellow (10YR6/6) mottles; medium clay, coarse sandy; moderate fine angular blocky structure; rough ped-fabric; firm to very firm consistence when moist; common prominent clay skins; pH 5.5; clear and wavy boundary to:
B22	75–140+	Greyish brown (2.5Y5/2) with many very coarse distinct yellowish brown (10YR5/6) mottles; light medium clay; weak medium subangular blocky structure; rough ped-fabric; weak consistence when moist; pH 7.0.
Management Considerations:
High permeability and water drainage capacity through the A horizon Texture contrast soil with clay percentage decreasing with subsoil depth Lateral flow of water along the top of the B horizon and little organic matter evident in the pale bleached A2 horizon Acidic to neutral surface and subsurface soil, strongly acidic subsoil. Less nutrient availability Many fine roots are observed to the top of the B horizon where higher clay content (35.5%) and sodic nature of B21 restricts root growth Distinct mottling and clayey subsoils indicate limitations to drainage Subsoil dispersion is very high, while there is insufficient aggregation in the upper soil (loose or very weak consistence)

Chemical Analysis:

Horizon	Depth (cm)	pH (water)	pH (CaCl₂)	EC dS/m	Exchangeable Aluminium cmol-/kg	Exchangeable Acidity cmol-/kg	Phosporus (Olsen) mg/kg	Total Nitrogen	Organic Carbon %	Exchangeable Cations cmol-/kg				Field Capacity (pF2.5)	Wilting Point (pF4.2)	Coarse Sand %	Fine Sand %	Silt %	Clay %
Horizon	Depth (cm)	pH (water)	pH (CaCl₂)	EC dS/m	Exchangeable Aluminium cmol-/kg	Exchangeable Acidity cmol-/kg	Phosporus (Olsen) mg/kg	Total Nitrogen	Organic Carbon %	Ca	Mg	K	Na	Field Capacity (pF2.5)	Wilting Point (pF4.2)	Coarse Sand %	Fine Sand %	Silt %	Clay %
Bulk sample	0–10	5.6	5.2	0.16			14	0.18	2.8
A1	0-5	5.6	5.2	0.18	<10	8.2			4.7	7.3	2.1	0.41	0.35	14	10.5	48.6	39.4	5.5	1.0
A21	5-30	5.9	5.5	<0.05	<10	<1.0				0.58	0.16	0.05	0.05	4.7	0.6	48.8	43.5	7.0	0.5
A22	30-45	6.4	6.1	<0.05	<10	<1.0				0.41	0.13	<0.05	0.05	4.7	0.7	51.8	40.8	5.5	0
A23	45-60	6.2	5.8	<0.05	<10	<1.0				0.23	0.12	<0.05	0.06	4.2	0.4	46.3	43.0	8.5	1.0
B21	60-75	5.1	4.2	0.17	280	12				0.79	4	0.32	1.7	23.7	13.2	37.1	21.8	2.0	36.5
B22	75-140+	5.5	4.5	0.16	95	4.5				0.64	2.5	0.14	1.5	14.5	6.4	48.3	32.2	3.5	14.5

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