PVI 9

Site: PVI 9	Land Unit: Monivae Basalt
*Aust. Soil Class.:* Bleached-Vertic (& Ferric-Sodic), Eutrophic, Brown CHROMOSOL (thick, 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: Valley flat below rises	Internal drainage: Moderately well drained

Soil Profile Morphology

A1	0-15 cm	Dark brown (10YR3/3), very fine sandy clay loam, weak coarse blocky structure, very firm consistence (dry), pH 5.3. Clear change to:
A2	15-40 cm	Brown (10YR5/3), conspicuously bleached (10YR7/1 dry), light fine sandy clay loam, massive structure, very firm consistence (dry), pH 5.9. Abrupt change to:
	Subsoil
B1	40-50 cm	Brown (10YR5/3), light medium clay, weakly structured, very strong consistence (dry), pH 6.6. Clear change to:
B21	50-65 cm	Brown (10YR5/3) with brownish yellow (10YR6/6 and 6/8) mottles, medium clay, very strong consistence (dry), many (30%) ferruginous nodules (2-4 mm), pH 6.6. Gradual change to:
B22	65-100 cm	Yellowish brown (10YR5/4) with brownish yellow (10YR6/6 and 6/8) mottles, medium heavy clay, moderate coarse blocky, parting to lenticular structure, very strong consistence (moist), many (20-40%) ferruginous nodules (2-6 mm), some manganese stains, pH 6.7. Transition to:
B23	100+ cm	Light brownish grey (10YR6/2) with many (40%) brownish yellow (10YR6/8) and dark red (2.5YR4/8) mottles, weak coarse prismatic, parting to moderate lenticular structure, rigid consistence (moist), few (5%) ferruginous nodules (2-6 mm), pH 6.7.

Key Profile Features

Strong texture contrast between surface (A) horizons and subsoil (B21) horizon
Conspicuously bleached subsurface (A2) horizon
Vertic (cracking) properties in deeper subsoil (i.e. lenticular structure)

Soil Profile Characteristics

	pH	Salinity Rating	Sodicity	Dispersion
Surface soil (A1 horizon)	Strongly Acid	Low	-	None
Upper subsoil (40-50 cm)	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
A1	0-15	5.3	4.8	0.10		4.8	1.5	0.12	0.18	10		38.1	9.3	3.1	40.2	31.0	17.5
A2	15-40	5.9	5.2	<0.05		2.7	0.77	<0.05	0.08	<10		24.3	4.2	3.2	50.1	31.5	11.0
B21	50-65	6.6	5.7	0.06	<0.01	3.6	4.2	0.12	0.45		6.7	27.0	12.7	6.7	38.2	22.5	34.0
B22	65-100	6.6	6.0	0.13		4.9	7.7	0.22	1.3		8.9	34.6	20.8	12.1	19.0	14.5	50.0
B23	100+	6.7	6.0	0.12		4.4	7.7	0.17	1.7

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