Soil/Landform Unit 28

Remnant forest stand at the Sheoaks

Area:

1635

0.12% of CMA region

Undulating rises on

marine shale and sandstone, and Neogene marine sands occur in the Sheoaks-Steiglitz area in the east of the Corangamite catchment. As part of the Midlands of the Western Uplands, a wide variety of vegetation classes are found across this unit including Lowland Forest, Heathy Dry Forest, Grassy Dry Forest and Sand Heathland. The dominant species include

Eucalyptus viminalis, E. obliqua, E. radiata, E. rubidia, E. ovata

and

E. pauciflora

. The unconsolidated gravel, sand and clay have a low inherent fertility and low water holding capacity. Land use is mainly grazing. Soils include sandy

mottled

texture contrast soils with

massive

subsoils. Structured subsoil equivalents may occur and there are minor occurrences of neutral mottled texture contrast soils. These soils tend to have shallow topsoils that are prone to sheet erosion, while the deeper soils in the drainage depressions suffer from gully erosion and soil salting.

Heathy dry forest

Component	1	2	3	4	5
Proportion of soil-landform unit	18%	4%	4%	37%	37%
CLIMATE Rainfall (mm)	Annual: 680
Temperature (^oC)	Minimum 8, Maximum 18
Precipitation less than potential evapotranspiration	October-March
GEOLOGY Age and lithology	Ordovician marine shale and sandstone, Neogene marine sand
Geomorphology	2.1.3 Dissected uplands associated with Cainozoic gravel and sediments of the Western Uplands
LANDUSE	Uncleared: Nature conservation; water supply Cleared: Sheep and cattle grazing; cropping (cereal)
TOPOGRAPHY Landscape	Undulating rises
Elevation range (m)	226-371
Local relief (m)	3
Drainage pattern	Dendritic
Drainage density (km/km²)	2.9
Landform	Hill		Drainage lines	Undulating plain	Flat plain
Landform element	Dry exposed slopes	Crest	Low lying areas	Well drained non-sandy areas	Poorly drained non-sandy areas
Slope and range (%)	15 (10-35)	3 (1-6)	1 (1-3)	1 (1-3)	0 (0-2)
Slope shape	Straight	Convex	Concave	Convex	Flat
NATIVE VEGETATION Ecological Vegetation Class	Lowland Forest (54.5%), Heathy Dry Forest (19.7%), Grassy Dry Forest (2.6%), Sand Heathland (1.6%), Other (1.2%)
Dominant species	E. obliqua, E. dives, E. radiata, E. viminalis		E. ovata, E. radiata, E. viminalis	E. viminalis, E. obliqua, E. radiata, E. rubidia, E. ovata, E. pauciflora	E. ovata
SOIL Parent material	In situ weathered sandstone and shale	In situ weathered sandstone and shale	Alluvium, clay, silt, sand, gravel	Unconsolidated gravel, sand and clay	Unconsolidated gravel, sand and clay
Description (Corangamite Soil Group)	Red mottled brown, grey or yellow gradational or texture contrast soils, fine structure (25)	Shallow stony red and brown, grey or yellow gradational soil (25)	Black gradational soil - variable (34)	Red mottled brown, grey or yellow texture contraast soil, fine structure (15)	Brown, grey or yellow sodic texture contrast soil, coarse structure (14)
Soil type sites	CLRA53, CLRA54, BD10	CLRA53, CLRA54, BD10	CLRA1, SW39, CLRA15	MM5109, SW63, OTR499	SW99, SW93, MM204
Surface texture	Fine sandy loam	Gravelly loam	Clay loam	Sandy clay loam to loamy sand	Clay loam
Permeability	High	High	Moderate to low	Moderate	Low
Depth (m)	2	0.5	>1	2	2
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS	Steep slopes and hardsetting surfaces result in significant overland flow. Sheet and rill erosion also occur from this overland flow. Soil compaction is also a limitation for soils with shallow topsoils.	Moderate slopes and hardsetting surfaces result in significant overland flow. Sheet and rill erosion also occur from this overland flow. Soil compaction is also a limitation for soils with shallow topsoils.	Moderate permeability subsoils and hardsetting surfaces result in significant overland flow. Sheet and rill erosion also occur from this overland flow. Soil compaction is also a limitation for soils with shallow topsoils. Gully erosion is also common in lower depressions.	Steep slopes and hardsetting surfaces result in significant overland flow. Sheet and rill erosion also occur from this overland flow. Gully erosion is also common in lower depressions.	Steep slopes and hardsetting surfaces result in significant overland flow. Sheet and rill erosion also occur from this overland flow. Soil compaction is also a limitation for soils with shallow topsoils.

Page top