ALRA066

Colluvial slopes leading to Mt William Creek		Site Code	ALRA066
		Location	Long Gully Road, Pomonal
		Landform	Scarp-footslope
		Geology	Grampians colluvium
		Element	Hillslope
		Slope	5%
		Aspect	North

Horizon	Depth (cm)
A11	0–10	Very dark grey (7.5YR2.5/1); loamy sand; massive (structureless); very weak consistence when moderately moist; many fine roots; pH 5.5; clear and wavy boundary to:		Parapanic, Humosesquic, Aeric PODOSOL
A12	10–30	Dark greyish brown (7.5YR4/1); loamy sand; massive (structureless); very weak consistence when dry; common very fine roots; pH 5.0; clear and smooth boundary to:
A2	30–55	Pinkish grey (7.5YR6/2); sporadically bleached (7.5YR7/1 dry); loamy sand; massive (structureless); very weak consistence when dry; common very fine roots; pH 5.5; abrupt and tongued boundary to:
Bhs	55–95	Olive yellow (2.5Y6/6); "coffee rock layer"; massive (structureless); very firm consistence when dry; moderately cemented discontinuous massive orstein pan; common very fine roots; pH 6.0; clear and wavy boundary to:
B2	95–120+	Light brownish grey (10YR6/2) with many very coarse prominent brownish yellow mottles; medium clay; massive (structureless); very firm consistence when dry; common prominent slickensides; common very fine roots; pH 6.5.
Management Considerations:
A horizon has been leached, particularly subsurface soil. High permeability and water drainage capacity through the A horizon. Coffee rock formed at the boundary of the A and B horizons from the accumulated deposits of organic matter and sesquioxides. Many fine roots are observed to the top of the B horizon where the orstein pan "coffee rock" provides an impediment to root growth (especially perennial and annual grasses). Old former tree roots penetrating the B horizon give effect of horizon tonguing. Lateral flow of water along the top of the B horizon is evident. Strongly acidic profile, low nutrient status with a low base nutrient status.

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	5.3	4.7	0.05			29	0.16	3.1
A11	0-10	5.5	4.9	0.05	<10	7.1			3.5	5.3	0.75	0.22	0.1	4.5	5.7	44.3	43.6	5.0	1.5
A12	10-30	4.3	3.9	<0.05	33	3.7			0.99	0.48	0.07	0.07	<0.05	4.3	1.1	45.2	46.8	4.0	2.5
A2	30-55	4.3	4	<0.05	19	1.6				0.19	<0.05	0.05	<0.05	7.4	0.7	45.2	47	5.5	2.5
Bhs	55-95	5.6	5.2	<0.05	19	8.5				0.55	0.12	0.06	0.07	21.3	2.4	37.1	49.1	6.5	2.5
B2	95-120+	5.3	4.5	<0.05	150					0.8	3.4	0.44	0.12	22.1	12.1	25.1	37.7	5.0	31.5

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