SFS15

Site: SFS 15	Land Unit: Monivae Basalt
*Aust. Soil Class.:* Ferric-Sodic, Eutrophic, Brown CHROMOSOL (confidence level 1)

General Land Unit Description:
The level to gently undulating basalt plains between Branxholm and Glenthompson consist of an association of Vertic or Ferric Brown Chromosols and Ferric Brown Sodosols. The Chromosols typically occur on the upper slopes and crests of very slight rises that may have scattered surface boulders, and Sodosols on the lower slopes and depressions. Sodosols or Vertosols, occasionally with a sporadic bleached subsurface horizon, are usually found in open depressions or drainage lines.

The soil at this site indicates the presence of gilgai microrelief. The face of pit shows features of ‘puff’, while sides and rear of pit shows features associated with ‘hollow’. The thick A2 horizon in the hollow is very high (>80%) with buckshot (3-10 mm), mostly magnetic, irregular rounded or subrounded (pitted).

Site Description:

Geology: Quaternary basalt	Landform pattern: Level to gently undulating plain
Position in landscape: Elevated plain	Internal drainage: Moderately well drained

Soil Profile Morphology

A1 (Ap)	0-20 cm	Very dark greyish brown (10YR 3/2 moist), greyish brown (10YR 5/2 dry) fine sandy clay loam. weakly to moderately pedal, sub-angular blocky to polyhedral (2–25 mm), firm (dry) to weak (moist) consistence. Clear change to:
A2c	20-35/37 cm	Very dark greyish brown (10YR 3/2 moist), (10YR 5/2 dry) to light greyish brown (10YR 6/2) dry, gravelly loam with hard magnetic ferromanganiferous concretions (3-10 mm), pH 5.6. Clear change (smooth and wavy, up to 50 cm in hollow) to:
	Subsoil
B21t	35-37-100 cm	Yellowish brown (10YR 5/4) with fine yellowish brown (10YR 5/8) and brown (10YR 4/3) mottles, light medium clay, fine buckshot (>10%), pH 6.6. Clear change to:
B22t (ss)	100+ cm	Mottled (fine – medium) grey (N6/) and brownish yellow (10YR 6/8), light olive brown (2.5Y 5/3) and yellowish brown (10YR 5/8), medium heavy to heavy clay, no buckshot, horizon cracked to base of pit and fissure traceable through B21 above, stress cutans (slickensides) on ped faces, pH 6.6.

Puff and Hollow

Subsoil mottling

Key Profile Features

Variation in soil profile features association with gilgai microrelief
Strong texture contrast between surface (A) horizon and subsoils (B21 horizon)

Soil Profile Characteristics

	pH	Salinity Rating	Sodicity	Dispersion
Surface soil (A1 horizon)	-	-	-	-
Upper subsoil (B21 horizon)	Slightly Acid	Low	Non-Sodic	None
Deeper subsoil (at 100+ cm)	Slightly Acid	Low	Sodic	None

Horizon	Horizon Depth	pH (water)	pH CaCl2	EC dS/m	NaCl %	Exchangeable Cations				Ex Al mg/kg	Ex Ac meq/100g	Field pF2.5	Wilting Point pF4.2	Coarse Sand (0.02-0.2mm)	Fine Sand (0.02-0.2mm)	Silt (0.02-0.02mm)	Clay (<0.002mm)
						Ca	Mg	K	Na
						meq/100g
A2	20-35	5.6	5.0	0.14		3.1	1.6	0.11	0.27	<10	9.6	27.5	10.2	19.8	33.5	22.0	21.0
B21	40-60	6.6	6.0	0.20		8.1	9.4	0.25	1.4		14	49.5	32.5	2.2	7.6	7.0	80.5
B21	60-80	6.7	6.1	0.18		6.5	9.1	0.23	1.7		14	48.8	31.1	3.4	8.7	6.5	7.8
B22	100+	6.6	6.0	0.27		6.5	12	0.1	2.7		13			3.4	9.0	11.5	72.5

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