NE38

Property: Rutherglen Research Institute	Paddock #: F
Australian Soil Classification: Bleached-Sodic, Eutrophic, Red CHROMOSOL	Northcote Factual Key: Dy 3.43
Great Soil Group: no suitable group	Map Unit: Type A
General Landscape Description: Higher area of plain.

NE38 Landscape

Soil Profile Morphology:

Surface Soil

A1	0-12 cm	Brown (7.5YR4/4); light fine sandy clay loam; weak coarse blocky structure; weak consistence (moist); pH 5.4; clear change to:	NE38 Profile
A2	12-30 cm	Pinkish brown (7.5YR6.5/4) conspicuously bleached (7.5YR8/2d); light fine sandy clay loam; structureless; firm consistence (dry); pH 6.0; clear change to:
Subsoil
B21	30-55 cm	Yellowish red (5YR5/8); light medium clay; weak medium polyhedral, parting to weak fine polyhedral structure; strong consistence (dry); manganese stains occur in patches; pH 6.8; gradual change to:
B22	55-80 cm	Brownish yellow (10YR6/6) with dark red (2.5YR4/6) mottles; light medium clay; moderate medium polyhedral, parting to fine polyhedral structure; strong consistence (dry); pH 6.0; clear change to:
B23	80-100 cm	Pale yellow (2.5Y7/4) [with yellowish red (5YR5/8) colours associated with root channels]; light medium clay; weakly structured; strong consistence (dry); pH 6.8; clear change to:
B24	100-140 cm	Very pale brown (10YR7/3) with brownish yellow (10YR6/8) mottles; light medium clay; moderate coarse polyhedral structure; strong consistence (dry); contains many (30%) manganese stqins along ped faces and very few nodules (up to 1 cm size); pH 7.0; clear change to:
B3	140+ cm	Light brownish grey (10YR6/2) with yellowish red (5YR5/8) mottles; light medium clay; strong coarse prismatic, parting to strong coarse blocky structure; strong consistence (dry); pH 8.0.

• Strong texture contrast between surface (A) horizons (15% clay) and subsoil (B21) horizon (38% clay).
• Conspicuously bleached subsurface (A2) horizon.

	The surface horizon is strongly acid. The upper subsoil is mainly slightly acid. The deeper subsoil is alkaline.		The level of soluble salts is very low throughout the soil profile.
	The top metre of the soil profile is non-sodic. The deeper subsoil is sodic and dispersive (Note that prismatic structure occurs below 140 cm depth).		The clay % increases sharply at the A/B horizon interface.

Horizon	Horizon Depth (cm)	Exchangeable Aluminium mg/kg	Exchangeable Acidity meq/100g	Field Capacity pF 2.5	Wilting Point pF 4.2	Coarse Sand (0.2-2.0 mm)	Fine Sand (0.02-0.2 mm)	Silt (0.002-0.02 mm)	Clay (<0.002 mm)
A1	0-12	10		27.7	7.2	2	53	22	15
A2	12-30			20.2	5	2	54	29	15
B21	30-55			25.1	12.7	1	37	25	38
B22	55-80			28.7	13.2	2	33	23	44
B23	80-100
B24	100-140
B3	140+

Management Considerations:

Whole Profile

• Plant available water capacity (PAWC) is considered to be low (estimated at 85 mm) for the top metre of the soil profile. This is based on available laboratory data.
• Exchangeable potassium levels are relatively high throughout the soil profile. According to Baker and Eldershaw (1993) levels of exchangeable potassium (relative to CEC) above 10% can result in magnesium deficiency.

• Although the surface horizons are non-sodic, slight dispersion occurs after remoulding. This indicates that some structural degradation may occur if the soil is cultivated in a moist-wet condition.
• The surface horizon has high fine sand (53%) and silt (22%) content. Organic matter is therefore important for maintaining soil aggregation and preventing slaking. The soil is likely to become 'powdery' when cultivated dry, which may result in surface sealing occurring.
• The surface soil has a low nutrient status (based on the sum of the exchangeable basic cations).

• The upper subsoil is non-sodic but disperses completely after remoulding. Deep tillage should therefore be avoided if the soil is in a moist to wet condition.
• Upper subsoil drainage should be reasonable due to the non-sodic conditions. Water movement will be restricted to some degree at the A/B horizon interface due to the reasonably large increase in clay content.
• The subsoil has a low-medium nutrient status (based on the sum of the exchangeable basic cations)
• The large amount of manganese segregations in the deep subsoil may restrict the growth of deeper rooted manganese sensitive plants.
• Deep profile drainage will be restricted by the sodic and strongly dispersive deep subsoil.

• Pasture since 1969.
• Sown to Trikkala clover (1990)