LP14

LP14 Landscape

Soil Profile Morphology

Surface Soil

A1	0-10 cm	Very dark greyish brown (10YR3/2); light medium clay; moderate coarse polyhedral structure; very strong consistence dry; pH 6.3; clear and wavy change to:	LP14 Profile
Subsoil
B21	10-30 cm	Very dark brown (10YR2/2) [with patches of red (2.5YR5/8)]; medium heavy clay; moderate coarse prismatic, breaking down to strong coarse blocky structure; very strong consistence dry; contains a few (2%) basalt fragments; pH 7.2; sharp and irregular change to:
B22	30-55 cm	Reddish brown (2.5YR4/4) with yellowish red (5YR4/6) and dark grey (10YR3/1) mottles; heavy clay; moderate coarse prismatic, breaking down to strong coarse blocky structure; firm consistence moist; contains a few (2%) basalt fragments; pH 7.9:
B3k	55-80 cm	Grey (10YR5/1) with brownish yellow (10YR6/8) mottles; medium heavy clay; strong consistence moist; contains many soft calcium carbonates and 50% of the horizon consists of basalt coarse fragments:
C	80+ cm	Weathered basalt.

• Lack of strong texture contrast between surface and subsoil horizons.

	pH	Salinity Rating	Sodicity	Dispersion
Surface (A1 horizon)	slightly acid	very low	non-sodic	water-stable
Subsoil (B21 horizon)	slightly alkaline	very low	non-sodic	none

Horizon	Horizon Depth	pH (water)	pH CaCl2	EC 1:5	NaCl	Exchangeable Cations
						Ca	Mg	K	Na
						meq/100g
A1	0-10	6.3	5.8	0.21		15.8	7.4	1.1	0.1
B21	10-30	7.2	6.3	0.05		17.4	9.4	0.8	0.5
B22	30-55	7.9	6.9	0.07		22.4	13.3	0.7	0.8
B3k	55-80
C	80+

Horizon	Horizon Depth	Ex Al mg/kg	Ex Ac meq/100g	Field pF2.5	Wilting Point pF4.2	Coarse Sand (0.2-2.0mm)	Fine Sand (0.02-0.2mm)	Silt (0.002-0.02mm)	Clay (<0.002mm)
A1	0-10	<10		34.6	20.6	4	32	18	43
B21	10-30			39.8	26.3	3	25	15	54
B22	30-55
B3k	55-80
C	80+

• The surface horizon has relatively moderate to high levels of organic carbon and total nitrogen.
• The overall nutrient status of the surface soil is high.

• The upper subsoil horizons are non-sodic and exchangeable calcium values are high in relation to other cations. This indicates that root and water movement will not be significantly restricted by poor subsoil chemistry. Root and water movement will be most restricted by the relatively shallow depth to weathered basalt.
• At depths greater than 55 cm, the pH levels will be high (ie. >8).

• Profile described by Mark Imhof (22/4/94)