PVI 8

Site: PVI 8	Land Unit: Monivae Basalt
*Aust. Soil Class.:* Melanic (& Ferric-Sodic), Eutrophic, Brown CHROMOSOL (thick, moderately gravelly, clay loamy surface) (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.

Site Description:

Geology: Quaternary basalt	Landform pattern: Level to gently undulating plain
Position in landscape: Upper slope of rise	Internal drainage: Moderately well drained

Soil Profile Morphology

A1	0-20 cm	Very dark greyish brown (10YR3/2), fine sandy clay loam, moderate coarse blocky, parting to moderate medium blocky structure, firm consistence (dry), many (25%) ferruginous nodules (2 - 5 mm), pH 5.5. Clear change to:
A2	20-35 cm	Brown (10YR4/3), light clay, firm consistence (dry), many (40%) ferruginous nodules (2-5 mm), common (20%) weathered basalt fragments (8-30 mm), pH 6.0. Clear change to:
	Subsoil
B21	35-50 cm	Yellowish brown (10YR5/4 and 10YR5/8), with strong brown (7.5YR5/6) mottles, medium clay, moderate to strong medium to fine polyhedral structure, strong consistence (dry), few (2-5%) iron nodules (2-5 mm), pH 6.6. Gradual change to:
B22	50-80 cm	Brownish yellow (10YR6/6) with dark red (2.5YR3/6) mottles, light clay, moderate to strong medium to fine polyhedral structure, strong consistence (dry), very few (1%) ferruginous and nodules (2 mm) and manganese stains, pH 6.7. Gradual change to:
B23	80-120 cm	Yellowish brown (10YR5/4) with strong brown (7.5YR5/6) light yellowish brown (10YR6/4) and dark red (2.5YR4/6) mottles, light clay, moderate to strong medium blocky structure, very firm consistence (dry), manganese stains, some weathered basalt, pH 6.7. Gradual change to:
BC	120+ cm	Light grey (10YR7/1) with brownish yellow (10YR6/8) and dark red (2.5YR4/8) mottles, light clay, strong consistence (moist), with weathered ferruginous basalt, pH 6.7.

Key Profile Features

Strong texture contrast between surface (A) horizons and subsoil (B21) horizon
Large amount of ferruginous nodules in surface (A) horizons

Soil Profile Characteristics

	pH	Salinity Rating	Sodicity	Dispersion
Surface soil (A1 horizon)	Strongly Acid	Low	Non-Sodic	None
Upper subsoil (35-50 cm)	Slightly Acid	Low	Non-Sodic	None
Deeper subsoil (at 80-120 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
A1	0-20	5.5	4.8	0.10		6.4	2.2	0.33	0.36	13	11	36.0	15.7	13.0	29.7	17.5	30.5
A2	20-35	6.0	5.2	0.07		5.3	3.1	0.20	0.37	<10	12	26.4	15.5	30.0	18.8	13.0	34.5
B21	35-50	6.6	6.0	0.07		4.5	6.4	0.15	0.53		11	37.6	27.0	7.0	12.4	10.5	68.5
B22	50-80	6.7	6.2	0.08		3.8	6.7	0.12	0.90			42.0	27.3	9.9	11.8	10.5	65.5
B23	80-120	6.7	6.2	0.09		3.3	7.0	0.11	1.4			43.7	31.5	4.5	9.6	11.0	73.5
BC	120+	6.7	6.3	0.14		2.1	6.3	0.07	1.8

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