CFTT6

Site: Yinnar	Location: APP species/seedlot trial VRV 142
*Aust. Soil Class.:* Bleached-Mottled, Magnesic, Brown KUROSOL	*Great Soil Group:* yellow soloth
Tech. Class: 021-6-42/4-1-2-32	General Landscape Description: Simple 5% slope to north east.
Geology: Fault breccia? Cretaceous in origin?

Soil Profile Morphology:

Surface Soil

A1	0 – 10 cm	Brown (10YR5/3), with few, mediu m, faint, pale brown (10YR6/3) mottles; clay loam; weak medium polyhedral structure; firm consistence, moderately moist; contains few subrounded, weathered siltstone gravels; pH 5.2; clear and sharp transition to:	CFTT6 Profile
A2	10 – 40 cm	Light yellowish brown (10YR6/4), with common, medium, distinct, brownish yellow (10YR6/6) mottles, fine sandy clay loam; massive structure, very firm consistence dry; contains few subrounded, weathered siltstone gravels; pH 5.3; clear and wavy transition to:
Subsoil
B21	40 – 50 cm	Brownish yellow (10YR6/6), with distinct, strong brown (7.5YR5/6) mottles common; light clay (increasing to light medium clay with depth); weak coarse polyhedral structure; very firm consistence moist; coarse subangular and tabular, weathered siltstone gravel common; pH 5.0; clear and wavy transition to:
B22	50 – 80 cm	Brown (10YR5/3) with many, coarse, prominent, dark grey (10YR4/1) and yellowish red (5YR4/6) mottles, medium heavy clay; moderate coarse polyhedral structure; strong consistence moist; contains many weathered siltstone cobbles; diffuse and smooth transition to:
B3	80 – 130 cm	Red (2.5YR5/6), with many, coarse, prominent, dark grey (10YR4/1) and very pale brown (10YR8/3) mottles; medium heavy clay; moderate very coarse polyhedral structure; strong consistence moist; includes tongues of dark grey heavy clay extending into the decomposing red decomposing fractured rock; abundant cobbles (subangular tabular, weathered siltstone).

Key Profile Features:

Strong texture contrast between surface (A) horizons (<25% clay) and subsoil (B21) horizon (60% clay).

Soil Profile Characteristics:

	pH	Salinity Rating	Sodicity	Dispersion
Surface (A1 horizon)	Strongly Acid	Very Low	Non-Sodic	None
Subsoil (B21 horizon)	Very Strongly Acid	Very Low	Non-Sodic	None

The soil profile is strongly acid to very strongly acid throughout.

The soil profile has a very low salinity rating throughout.

The levels of exchangeable aluminium increase
in the very strongly acid subsoil to high levels.

The clay content increases markedly at the A/B horizon interface.

Horizon	Horizon Depth	pH (water)	pH CaCl2	EC 1:5	NaCl	Exchangeable Cations
						Ca	Mg	K	Na
						Meq/100g
A1	0-10	5.2	4.3	0.1		1.9	1.5	0.22	0.32
A2	10-40	5.3	4.6	<0.05		0.58	1.1	0.06	0.17
B21	40-50	5	4.2	0.1		0.63	7.2	0.11	0.63

Horizon	Horizon Depth	Ex Al mg/kg	Ex Ac meq/100g	Field pF 2.5	Wilting Point pF4.2 g/100g	Coarse Sand (0.2-2.0mm) %	Fine Sand (0.02-0.2mm) %	Silt (0.002-0.02mm) %	Clay (<0.002mm) %


A1	0-10	88	14	30.1	9.3	10.4	36.1	28.5	17.5
A2	10-40	97	9.7	29	9	9.6	37.4	25	25
B21	40-50	260	13	41.6	25	12.3	16.1	8	59.5

Management Considerations:

The high exchangeable aluminium levels in the very strongly acid subsoil may affect the growth of aluminium sensitive species.
The subsoil has a very low exchangeable calcium:magnesium ratio (<0.1). Calcium deficiency may result.

Notes:

Weathered siltstone impeding at 130 cm. Profile looks like transported material over “breccia” material similar to Cretaceous mudstone, although redder in colour. This soil does not fit the description of Boolarra loam.

Profile Sampled by: Ian Sargeant and Justin Wong (2/6/99)

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