Dromana

Dromana - Symbol: Dr

This mapping unit delineates the gently sloping alluvial fans and colluvial deposits that were deposited as a result of erosion of steep adjoining hills, mainly north of Arthurs Seat, south of Mount Martha and north of Baxter. Originally these slopes supported a grassy woodland.

The surface soils are grey sandy loams to fine sandy loams about 150 mm thick, overlying a bleached but similarly textured subsurface horizon. Mottled yellowish brown and pale grey medium clays abruptly occur from about 450 mm depth. The bleached subsurface layer, generally pale brownish grey in colour, sets very hard when dry and becomes dilatant or “spewy” when wet, resulting in trafficability problems during wet periods. Small pellets of ferruginous nodules (i.e. “buckshot”) often occur just above the clay subsoil. The surface soil pH’s are around 5.5 to 6.0, with the subsoil pH’s about 5.5 to 6.5. It is likely that the subsoils are sodic and may require gypsum and lime if they are to support orchards or viticulture. These soils are best described as Yellow or Grey Sodosols using the Australian Soil Classification.