SW91

Location: Batesford

Australian Soil Classification: Vertic, Hypercalcic, Black CHROMOSOL (moderate profile depth)

General Landscape Description: Gently undulating plain.
Site Description: Flat.
Geology: Newer volcanics

Soil Profile Morphology:

Surface Soil

Ap	0-10 cm	Brown (10YR4/3 moist); loam; weak consistence dry; pH 6.8; abrupt change to:	SW91 Profile
A12	10-30 cm	Very dark grey (10YR3/1 moist); clay loam, fine sandy; very firm consistence dry; medium to coarse (10-30 mm) granular to polyhedral structure; rough faced peds; pH 6.6; clear change to:
Subsoil
B21tg	30-50/70 cm	Very dark grey (10YR3/1 moist) to very dark grayish brown (10YR3/2 moist) with dark greyish brown (2.5Y4/2 moist) and reddish brown (5YR4/4 moist) mottles; medium to heavy clay; smooth faced peds; moderate medium (<50 mm) prismatic, parting to coarse (20-50 mm) angular blocky/polyhedral structure; moderately vertic with prominent slickensides at base; strong consistence dry; pH 7.3; sharp and wavy change to:
B22k/R	50/70-80 cm	Soft whitish carbonate; rounded weathered and fractured basalt; sharp and wavy change to:
R	80+ cm	Fractured basalt.

• Strong texture contrast between surface (A) horizons and subsoil (B21) horizon.
• Vertic features (slickensides) in subsoil.
• Calcium carbonate segregations in deeper subsoil.
• Moderate soil profile depth (overlying fractured basalt).

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

The surface is slightly acid. The subsoil is slightly alkaline.

Salinity rating is low in the surface and very low in the subsoil.

The soil is non sodic throughout the profile.

The clay content increases markedly at the A/B boundary.

Horizon	Sample Depth (cm)	Organic Carbon %	Nitrogen %	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	0-10	2.4	0.20	28.3	12.4	16	36	16	25
A12	10-25			32	15.9	8	38	18	31
Btg	35-50			51.2	28.4	4	20	9	60

Notes:

• Between this site and the Barwon River crossing the soil varies across the plain with small changes in elevation and slope. Calcium carbonate (CaCO₃) is ubiquitous and prominent. Soil surface horizons range from nearly black (usually very dark grey) through to dark grey to brown. Sometimes crusting and self-mulching. Soil depth is generally <1.0 m but some small pockets of grey clay >2.0 m, which are strongly vertic, but these are rare occurrences and associated with lower spots, probably silted drainage lines or depressions.