Calcarosols (often called ‘mallee loams’,‘mallee sands’ or ‘calcareous earths’) are soils formed on calcareous aeolian sediments of variable texture. They generally have a small, gradual increase in clay content with depth (ie. not as strong texture contrast between surface soil and subsoils as compared to Sodosols). Lime is abundant in subsoils in soft form, in nodules and sometimes as hard blocks. The soil profile is alkaline throughout and sodicity and salt levels are often high in the deeper subsoils.
Calcarosols are usually associated with unconsolidated, highly calcareous coarse to medium textured parent materials. They are commonly found on undulating plains and sand dunes north of Dimboola and north-east of Warracknabeal. Some minor occurences occur in the Kaniva to South Australian border area.
Calcarosols Wimmera Region
|This map presents a broad overview of the distribution of Calcarosols in the Wimmera region. A number of soil surveys have been done in this region (see Soil and Land Survey Directory) at varying scales and intensity. In some areas very little soil survey has taken place. This map therefore provides a broad indication only of the distribution of Calcarosols in the Wimmera region.|
Soils are difficult to map at this broad scale because of their diversity. Even in relatively small areas, a number of soils may occur which relate to differences in topography and landscape position. Variation in some of the major soil profile properties can also occur within these mapped areas. Any cropping enterprise should be based on a proper on-site assessment of the soil and landscape.
Calcarosol in the Kaniva region.
Soil texture has a big influence on agronomic importance of the land. Sands are easily worked but have low fertility reserves and are very prone to wind erosion. Heavier textured Calcarosols are more fertile and less erodible, but more prone to salting and to hardsetting when overcultivated.