Location: Irrewillipe
Australian Soil Classification: Ferric-Sodic, Mesotrophic, Grey CHROMOSOL
Map Unit: Map Unit 157 (Maher and Martin, 1987).
General Landscape Description: Gently undulating plain.
Site Description: Grazing paddock (dairy).
Geology: Tertiary - Moorabool Viaduct Formation.
SW38 Landscape |
A1 | 0-15 cm | Very dark brown (10YR2/2); light fine sandy clay loam; moderate coarse polyhedral, parting to moderate medium polyhedral structure; weak consistence moist; pH 6.1: | SW38 Profile |
A21 | 15-45 cm | Dark brown (10YR3/3), sporadically bleached; rusty root channel mottling; light fine sandy clay loam; weak medium blocky, parting to moderate medium blocky structure; weak consistence moist; pH 5.7: | |
A22 | 45-55 cm | Dark brown (10YR4/3); fine sandy clay loam; contains very many (80%) ferruginous nodules (4-20 mm in size); pH 6.4: | |
Subsoil | |||
B21 | 55-90 cm | Dark brown (7.5YR4/2) with many strong brown (7.5YR5/8) mottles; light medium clay; strong medium blocky, parting to strong fine polyhedral structure; firm to strong consistence moist; contains a few (5-10 %) ferruginous nodules (4-20 mm in size); pH 6.7: | |
B22 | 90+ cm | Light brownish grey (10YR6/2) with reddish yellow (7.5YR6/8) and red (2.5YR4/8) mottles; medium clay; strong medium blocky, parting to strong fine polyhedral structure; firm consistence moist; contains a few (5-10 %) ferruginous nodules; pH 6.8. |
pH | Salinity Rating | |||
Surface (A1 horizon) | Slightly Acid | Very Low-Low | Non-Sodic | None |
Subsoil (B21 horizon) | Slightly Acid | Very Low | Non-Sodic | None |
Deeper subsoil (at 90+ cm) | Slightly Acid | Very Low | Non-Sodic | None |
The surface is slightly acid, becoming moderately acid at 30 cm. The subsoil is slightly acid. | The salinity rating is very low throughout. | The clay content increases markedly at 55 cm depth. |
Horizon | Horizon Depth (cm) | pH (water) | pH (CaCl2) | EC (dS/m) | Exchangeable Cations | |||
Ca | Mg | K | Na | |||||
meq/100g | ||||||||
A1 | 0-15 | 6.1 | 5.4 | 0.08 | 6 | 0.4 | 0.2 | 0.05 |
A21 | 15-45 | 5.7 | 4.9 | 0.07 | 2.9 | 0.3 | 0.05 | 0.05 |
A22 | 45-55 | 6.4 | 5.6 | 0.05 | 1.4 | 0.9 | 0.05 | 0.05 |
B21 | 55-90 | 6.7 | 6 | 0.08 | 4.6 | 6 | 0.2 | 0.6 |
B22 | 90+ | 6.8 | 6 | 0.07 | 3.9 | 5.8 | 0.1 | 0.6 |
Horizon | Horizon Depth (cm) | Acidity meq/100g | Oxidisable Organic Carbon % | Total Nitrogen % | Field Capacity pF2.5 | Wilting Point pF4.2 | 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 | 0-15 | 3.6 | 0.24 | 29 | 9.3 | 7 | 54 | 17 | 14 | |
A21 | 15-45 | 27.4 | 6.7 | 9 | 55 | 18 | 14 | |||
A22 | 45-55 | 25.9 | 9.1 | 17 | 47 | 15 | 21 | |||
B21 | 55-90 | 10 | 52.8 | 31.4 | 2 | 12 | 5 | 78 | ||
B22 | 90+ | 48.4 | 27.5 | 3 | 18 | 9 | 72 |