MM548

Site: MM548	Land Unit: Glenthompson Granites
*Aust. Soil Class.:* Ferric, Mottled-Subnatric, Brown SODOSOL (confidence level 2)

General Land Unit Description:
This land unit comprises a small area of Cambrian granites south of Glenthompson. The soils tend to have a strong texture contrast with a sodic subsoil. There are many ferromangaiferous nodules above the clay, which is common to many soils in the study area. The mottled subsoil and the bleached A2 horizon indicate that the soil is imperfectly drained. This feature, together with the ferric horizon, would be the major restriction for land use.

Site Description:

Geology: Cambrian granite	Landform pattern: Gently undulating plain
Position in landscape: Low crest	Internal drainage: Imperfectly drained

Soil Profile Morphology

A1	0-25 cm	Very dark greyish brown (10YR3/2) sandy loam, very weak consistence, a few fine segregations, pH 5.3. Clear transition to:
A2	25-40 cm	Brown (10YR5/3) sandy loam, conspicuously bleached light grey (10YR7/2), many ferromanganiferous nodules. Sharp transition to:
	Subsoil
B21	40-55 cm	Yellowish brown (10YR5/4) medium heavy clay, red (2.5YR4/6) mottles, strong blocky structure (5-10 mm), pH 7. Transition to:
B22	55+ cm	Yellowish brown (10YR5/4), medium heavy clay, red (2.5YR4/6) mottles, strong blocky structure (5-10 mm), pH 7.

Key profile features:

Strongly acidic topsoil
Bleached A2 horizon
Strong texture contrast between topsoil and subsoil
Many ferromanganiferious nodules in A2 horizon
Topsoil dispersive when worked when wet
Top of the subsoil dispersive when worked when wet
Deeper subsoil strongly sodic

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