Site 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.

General Landscape Description: Higher area of plain.
Soil Mapping Unit: Type A.

Site NE38 Landscape

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:	Site 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 stains 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, breaking 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 top metre of the soil profile is non-sodic. The deeper subsoil is sodic and dispersive. Note: prismatic structure occurs below 140 cm depth.
	The level of soluble salts is very low throughout the soil profile.		The clay % increases sharply at the A/B horizon interface.

• 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 Cation Exchange Capacity) 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 deep rooted manganese sensitive plants.
• Deep profile drainage will be restricted by the sodic and strongly dispersive deeper subsoil.

• Pasture since 1969.
• Sown to Trikkala clover in 1990.