LP39

Soil Site LP 39 Landscape

Soil Profile Morphology

Surface Soil

A1	0-10 cm	Dark reddish brown (5YR3/3); fine sandy loam; hardsetting surface condition; moderate coarse granular structure; firm consistence dry; contains a few (10%) shale fragments and very few (1%) quartz fragments; pH 5.7; clear and wavy change to:	Soil Site LP39 Profile
Subsoil
B21	10-30 cm	Red (2.5YR5/8); fine sandy clay loam; weak coarse blocky structure; strong consistence dry; contains a few (10%) shale fragments (3-5 mm size); pH 5.3; clear and wavy change to:
B22	30-40 cm	Reddish yellow (5YR6/8); fine sandy clay loam; moderate medium blocky structure; very firm consistence dry; pH 5.0; wavy change to:
C	40 cm +	Weathered rock.

• Lack of strong texture contrast between surface (A) and subsoil (B) horizons.
• Shallow soil profile depth.
  

	pH	Salinity Rating	Sodicity	Dispersion
Surface (A1 horizon)	moderately acid	very low	non-sodic	none
Subsoil (10 - 30 cm)	strongly acid	very low	non-sodic	slight1
Deeper subsoil (30 - 40 cm)	strongly acid	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	5.7	4.7	0.08		2.4	1.3	0.4	0.1
B21	10-430	5.3	4.4	<0.05		0.6	0.7	0.2	0.1
B22	30-40	5	4.2	0.05		0.4	0.7	0.2	0.1
C	40

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			26.5	11.7
B21	10-430	38	3.8	24.2	14.2	7.7	46.7	23.5	23
B22	30-40	96	6	25.4	14.2
C	40

• Plant available water capacity (PAWC) will be low due to the shallow effective rooting depth. Plants are likely to suffer moisture stress during dry periods.

• The surface soil has a low inherent fertility (based on the sum of the exchangeable basic cations).
• The surface soil is relatively shallow and should be protected from sheet erosion by maintaining adequate surface cover. Organic carbon levels are reasonable at this site. Organic matter is important for enhancing soil fertility, water holding capacity and aggregate stability.
• The surface soil is moderately acid which indicates that aluminium toxicity should not be a problem. Ideally, however, a pH/aluminium test is best performed on a bulked sample taken from across the paddock. Lime may have been used on this paddock.

• The subsoil is strongly acid. As a result exchangeable aluminium levels are reasonably high – which may affect sensitive species (e.g. lucerne, phalaris).
• The inherent fertility of the subsoil is very low (based on the sum of the exchangeable basic cations).

• Profile described by Mark Imhof, Paul Rampant and Karen De Plater (21/3/95)