6 Brown, yellow and grey strongly sodic and non-alkaline mottled texture contrast soils on Cretaceous sediments

These soils occur on drier and moderately moist aspects of the Southern Uplands underlain by Cretaceous sediments.

The surface soil is a moderately fine structured dark organic fine sandy loam to clay loam (5-40 cm deep) with a clear change to a massive (occasionally weak structure) bleached hardsetting subsurface sandy loam to clay loam soil (A2 horizon 30–60 cm) which clearly overlies a dark medium to heavy clay subsoil which is often mottled particularly with depth. Subsoil structure ranges from coarse to medium depending on texture and cation dominance (coarser structure indicates higher sodicity). Subsoils may be strongly acidic or sodic at depth as an intergrade to the sodic soils. Soil depth is usually greater than 100 cm before grading into weathered sandstone, often clearly. Combined with steep slopes these soils are slip prone.

Notable characteristics include: high clay content with fine sand component, weathered deep profiles with little rock fragment content, texture contrast with variable surface soil depth, pale mottled lower subsoils which can be sodic, and high nutrient capacity (magnesic) despite relatively low pH.

Soil Sites

Site Code	Soil-landform unit	Component	ASC	FK	1:100 000 mapsheet
OTR424	64	Mid slope	Bleached, Eutrophic, Grey Kurosol	Dy2.21	T7520 - Princetown
OTR735	64	Mid slope	Bleached-sodic, Magensic, Brown Kurosol	Db2.21	T7620 - Otway
SW71	92	Waxing upper slope	Bleached-Vertic (& Mottled) Magensic, Brown Chromosol	Db2.41	T7621 - Colac
SW72	92	Mid slope	Bleached-Vertic, Magnesic, Brown Chromosol	Db2.41	T7621 - Colac

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