LP49

LP49 Landscape

Soil Profile Morphology

Surface Soil

A11	0-5 cm	Dark brown (7.5YR3/4); clay loam (fine sandy); moderate fine granular structure; firm consistence dry; pH 7.4; clear change to:	LP49 Profile
A12	5-20 cm	Dark brown (7.5YR3/4); clay loam (fine sandy) grading to light clay with depth; strong coarse blocky structure; strong consistence dry; pH 8.0; clear and wavy change to:
Subsoil
B21	20-30 cm	Reddish brown (5YR4/4); light medium clay; moderate medium prismatic, parting to moderate coarse blocky structure; very firm consistence dry; pH 8.2; clear and wavy change to:
B22k	30-60 cm	Reddish yellow (5YR6/6); clay loam (fine sandy); weak prismatic structure; contains many (30%) hard calcareous nodules and (20%) fine-earth carbonates; firm consistence dry; pH 8.8; gradual change to:
B23k	60-90 cm	Reddish yellow (7.5YR6/6); light clay; weakly structured; contains very many (60%) fine-earth carbonates; very firm consistence dry; gradual and wavy change to:
B24	90+ cm	Reddish yellow (7.5YR6/6); medium clay; strong coarse polyhedral structure; very firm consistence dry; pH 9.4.
NOTE: This site corresponds to the Type K soil as described by Skene (1971).

• No major texture contrasts within the profile (i.e. gradational change).
• Calcareous throughout profile.

	pH	Salinity Rating	Sodicity	Dispersion
Surface (A1 horizon)	slightly alkaline	medium	non-sodic	none1
Subsoil (B21 horizon)	moderately alkaline	low	non-sodic	none
	very strongly alkaline	high	strongly sodic	strong
1 Slight dispersion after remoulding

Horizon	Horizon Depth	pH (water)	EC 1:5	NaCl	Exchangeable Cations
					Ca	Mg	K	Na
					meq/100g
A11	0-5	7.4	0.21		14	2.6	2.2	0.2
A12	5-20	8	0.07		17	2.8	1.5	0.3
B21	20-30	8.2	0.08		20	3.8	1.5	0.3
B22K	30-60	8.8	0.12		12	3.3	0.4	0.4
B24	90+	9.4	0.95	0.13	3.7	10	1.2	7.4

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)
A11	0-5			25.4	17.3	15	33	12	35
A12	5-20			28.1	19.4	16	31	10	40
B21	20-30			33.4	23.9	14	25	8	50
B22K	30-60
B24	90+

• In general, management strategies for all soils should aim to increase organic matter levels in the surface soil; minimise the degradation of soil aggregates and porosity; promote the development of stable biopores; improve the calcium status of the ion exchange complex (particularly when sodium is a significant part), and break up any hardpans. Less frequent tillage; using less aggressive implements, and working the soil at optimum moisture conditions can all assist in maintaining soil aggregation and porosity as well as reducing the breakdown of organic matter.

• The surface soil organic matter content and total nitrogen level is relatively high for a cropping soil. The overall nutrient status is also high.
• The relatively high wilting point value (17%) for the surface soil means that plants will not be able to fully utilise light rains falling on relatively dry soil as there will be insufficient moisture to wet the soil above the wilting point value.
• The surface horizons are relatively deep and well structured providing a suitable establishment and rooting environment for plants

• The subsoil is very strongly alkaline from 30 cm depth. This indicates that phosphorus and some trace elements such as iron, manganese, zinc and copper may be poorly available to plants and deficiencies may occur. Deficiencies can be determined by plant tissue analysis. Boron toxicity can also occur in strongly alkaline soils.
• The upper subsoil is non-sodic and non-dispersive. It is therefore likely to present fewer limitations to rot and water movement into the subsoil compared to more sodic subsoils that occur in the region.

• Lupins not grown successfully.
• Barley has been grown.