These soils occur extensively on the basic volcanic plains, generally in the less stony areas. The organic surface soils (10–15 cm) overlie a weakly pedal to massive subsurface (A2) horizon (to 20–50 cm) with some ferruginous (or ferromanganiferous) gravel, which abruptly overlies a brown coarse structured hardsetting mottled (red, orange) medium to heavy clay with some ferromanganiferous) gravel, which may overlie a highly calcareous clay horizon (90 cm or greater), which will overly parent material, usually with a clear boundary (>150 cm). Depth for the particular boundaries may vary due to the swelling nature of the soil, so that a subsurface horizon may not exist with clay close to the surface, but appear and be quite deep (and hence a greater depth to the heavy clay subsoil within metres). This is called gilgai or crabhole terrain; the components are called puffs and shelves. The lower subsoil may be more olive/yellow-brown at depth, indicating anaerobic conditions. Notable features include: texture contrast, coarse structure (columnar), very hard when dry, strong sodicity in the subsoil and possibly the surface soil, variable vertical depth and horizontal distance characteristics of surface soil, free carbonate (calcareous) at depth, deep profiles, and some ferromanganiferous gravel. |
Site Code | Soil-landform unit | Component | ASC | FK | 1:100 000 mapsheet |
Lower slope | Eutrophic, Mesonatric, Brown Sodosol | Dy3.43, Dg2.43 | T7621 - Colac | ||
Flat | Eutrophic, Mottled-Mesonatric, Brown Sodosol | Db2.42 | T7622 - Ballarat | ||
MM414 | Flat | Vertic, Mottled-Mesonatric, Brown Sodosol | Dy3.32 | T7522 - Skipton | |
MM432 | Upper slope | Ferric, Mottled-Mesonatric, Brown Sodosol | Dy3.33 | T7522 - Skipton | |
MM5011 | Mid slope | Hypercalcic, Mottled-Mesonatric, Brown Sodosol | Db2.13 | T7721 - Geelong | |
Flat | Eutrophic, Mottled-Hypernatric, Brown Sodosol | Dy3.43 | T7721 - Geelong | ||
MM5085 | Flat | Ferric, Mottled-Hypernatric, Brown Sodosol | Dy3.43 | T7721 - Geelong | |
Plain | Manganic, Mottled-Mesonatric, Yellow Sodosol | Dy3.42 | T7622 - Ballarat | ||
SFS11 | Lower slope | Vertic, Mottled-Mesonatric, Grey Sodosol | Dy3.43 | T7522 - Skipton |