GL87

Site: GL87	Land Unit: Digby
*Aust. Soil Class.:* Melanic, Natric, Black CHROMOSOL (confidence level 1)

Soil pit GL87 auger

General Land Unit Description:
As with the Merino Tablelands land unit, the Digby land unit also occurs on the Cretaceous nonmarine sandstone of the Merino Tablelands. The soils on the Digby land unit differ from the Merino Tablelands land unit as they tend to be slightly more acidic in the top of the subsoil and have more ferruginous nodules (Ferric Brown Chromosols). The division between the two land units is highlighted in recent radiometric imagery. Black Chromosols, Dermosols and Vertosols, similar to the Merino land unit also occur.

Site Description:

Slope: 12%	Geology: Cretaceous non-marine sandstone
Landform pattern: Undulating rises	Position in landscape: Lower slope
Internal drainage: Moderately well drained

Soil Profile Morphology

A1	0-20 cm	Very dark grey (10YR3/1) loam, medium subangular blocky structure (2-5 mm), weak consistence when dry to moderately moist, pH 5.6; transition to:
A31	20-35 cm	Very dark greyish brown (10YR3/2) light clay, massive structure, firm consistence when dry to moderately moist, very few small ferruginous nodules (2-5 mm), pH 5.6; transition to:
A32	35-50 cm	Dark greyish brown (10YR4/2) light clay, massive structure, firm consistence when dry to moderately moist, pH 6.1; transition to:
	Subsoil
B21	50-80 cm	Very dark greyish brown (10YR3/2) medium clay, weak to moderate subangular blocky structure (5-10 mm), very firm consistence when moderately moist, pH 6.7; transition to:
B22	80-105 cm	Very dark greyish brown (2.5Y3/2) light medium clay, few faint yellow mottles, medium angular blocky structure, very firm consistence when moderately moist, pH 8; transition to:
B23	105-120 cm	Light olive brown (2.5Y5/4) light medium clay, many distinct yellow and orange mottles, weak structure, very firm consistence when moderately moist, pH 7; transition to:
B24	120-140 cm	Light olive brown (2.5Y5/4) medium clay, medium structure, very firm consistence when moderately moist, pH 7.5; transition to:
B3	140+ cm	Light yellowish brown (2.5Y6/4) medium clay, many prominent orange mottles, very firm consistence when moderately moist, pH 8.

Key profile features:

Strong texture contrast between topsoil and subsoil
Mottled subsoil
Sodic subsoil
Deeper topsoil dispersive when worked when wet
Subsoil dispersive when worked when wet

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