ALRA068

Alluvial plain bordering undulating plain		Site Code	ALRA068
		Location	Moyston West Road
		Landform	Alluvial plain
		Geology	Quaternary alluvium
		Element	Plain
		Slope	2%
		Aspect	North
Horizon	Depth (cm)
A1	0–5	Very dark greyish brown (10YR3/2); loam, medium sandy; weak coarse prismatic structure parting to weak fine subangular blocky structure; rough fabric; weak consistence when moderately moist; common fine ferruginous-organic root lining segregations; pH 6.0; abrupt boundary to:		Epihypersodic, Massive, Grey VERTOSOL
B1	5–15	Dark greyish brown (10YR4/2); loamy clay; moderate coarse prismatic parting to weak fine to medium subangular blocky structure; rough fabric; very strong consistence when dry; few fine ferruginous-organic root lining segregations; pH 6.5; clear boundary to:
B21	15–70	Dark grey (5Y4/1); medium heavy clay; moderate coarse prismatic parting to weak medium to coarse polyhedral structure; very strong consistence when dry; common distinct slickensides; pH 7.0; clear boundary to:
B22	70–100	Olive grey (5Y5/2)with many medium distinct yellowish brown (10YR5/8) mottles; medium heavy clay; subplastic; strong coarse prismatic parting to fine prismatic structure; smooth fabric; firm consistence when moderately moist; common prominent slickensides; pH 7.0; gradual boundary to:
B3	100–135+	Greyish brown (2.5Y5/2) with common medium distinct dark yellowish brown (10YR3/4) mottles; heavy clay; strong coarse prismatic parting to fine prismatic structure; smooth fabric; firm consistence when moist; pH 7.0.
Management Considerations:
Acidic surface soil becoming alkaline and then neutral with depth Cracking clay profile with coarse structure, roots will follow this structure, but must cope with shrinkage properties Soil structure exhibits vertical cracking from below A1 horizon with the B22 horizon sub plastic in nature Subsoil has high inherent fertility based upon the sum of the exchangeable basic cations. Note magnesic tendency in subsoil High salinity (EC) in lower subsoil. Dispersion tests indicate moderate dispersion in upper subsoil and nil to slight dispersion in the lower subsoil due to concentration of soluble salts Sand lenses are evident within B3 and clay proportion decreases with depth

Chemical Analysis:

Horizon	Depth (cm)	pH (water)	pH (CaCl₂)	EC dS/m	NaCl %	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	NaCl %	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	5.4	5.1	0.49				140	0.77	12
A1	0-5	5.4	5.2	0.73	0.14	17.0	20			>12.0	14.0	9.5	0.6	0.7	56.6	34	13.4	10.9	22.5	30.5
B1	5-15	6.7	6.3	0.54	0.09	9.0	4.9				7.9	12.0	0.4	1.9	35.2	20.4	7.0	8.8	29.5	51.0
B21	15-70	8.0	7.6	1.1	0.21		-				6.5	17.0	0.8	4.8	37.5	19.3	2.3	11.0	29.5	57.0
B22	70-100	7.6	7.4	2.2	0.53		-				6.1	19.0	0.4	7.9	43.1	22.4	0.3	10.4	31.5	56.5
B3	100-135+	7.4	7.2	2.3	0.03		3.2				5.9	17.0	0.4	8.7	43.9	25.1	0.4	10.7	36.0	49.0

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