Soil/Landform Unit - Joel south hills

The cleared hills of this landscape are extremely vulnerable to gully and tunnel erosion

Area: 4258 ha

0.18% of CMA region

As part of the Dissected Western Uplands, this group of hills is slightly lower in elevation and has slightly less steep slopes than those of the Pyrenees Ranges. These hills have been largely cleared which makes them distinct from the predominantly uncleared remainder of the Pyrenees Ranges. Hillslopes, colluvial footslopes and drainage depressions are well defined on these hills where gully and tunnel erosions are major limitations and threats. Subsoils are extremely prone to gullying where exposed due to the poor aggregate stability of subsoils. Land use is mainly grazing however dryland cropping and recently viticulture are more common especially on footslopes. Remnant native vegetation communities recorded include Heathy Dry Forest, Grassy Forest, Box Ironbark Forest, Hillcrest Herb-rich Woodland and Grassy Woodland.

Looking south from Landsborough West
	Erosion control works on extremely erosive hillslopes

Component	1	2	3	4	5
Proportion of soil-landform unit	15%	20%	30%	20%	15%
CLIMATE Rainfall (mm)	Annual: 620
CLIMATE Rainfall (mm)	Annual: 620
Temperature (^oC)	Minimum 8, Maximum 19
Precipitation less than potential evapotranspiration	October–April
GEOLOGY Age and lithology	Quaternary fluvial gravel, sand and silt; Cambrian marine sandstone, siltstone and biotite schist (St Arnaud Group); Devonian granite (Ben Nevis Granite)
GEOLOGY Age and lithology
Geomorphology	2.1.2 Hills, valley slopes and plains on granitic Palaeozoic rock of the Dissected Western Uplands
LANDUSE	Uncleared areas: nature conservation Cleared areas: dryland cropping; sheep grazing; viticulture
LANDUSE
TOPOGRAPHY Landscape	Hills and crests
TOPOGRAPHY Landscape	Hills and crests
Elevation range (m)	229–469
Local relief (m)	80–120
Drainage pattern	Dendritic
Drainage density (km/km²)	0.7
Landform	Hills and hillslopes			Colluvial footslopes	Drainage lines
Landform element	Steep crest	Upper slope	Mid slope	Lower slope	Drainage depression
Slope and range (%)	25 (20-40)	20 (10-35)	12 (3-20)	6 (3-18)	5 (2-20)
Slope shape	Convex	Convex	Linear	Concave	Concave
NATIVE VEGETATION Ecological Vegetation Class	Box Ironbark Forest (30.7%), Heathy Dry Forest (24.3%), Grassy Dry Forest (16.7%), Other (7.2%)
NATIVE VEGETATION Ecological Vegetation Class
SOIL Parent material	In situ marine sandstone, siltstone and biotite schist and intrusive granites	In situ marine sandstone, siltstone and biotite schist and intrusive granites	In situ marine sandstone, siltstone and biotite schist and intrusive granites	Colluvial and alluvial gravel, sand and silt	Alluvial gravel, sand and silt
SOIL Parent material				Colluvial and alluvial gravel, sand and silt	Alluvial gravel, sand and silt
Description (Corangamite Soil Group)	Red texture contrast soils (1)	Red texture contrast soils (1)	Red texture contrast soils (1) and sodic red texture contrast soils (2)	Yellow texture contrast soils (3) and sodic red texture contrast soils (2)	Yellow texture contrast soils (3) and sodic red texture contrast soils (2)
Soil type sites	LP83, DOAGW31, LP82	LP83, DOAGW31, LP82	LP83, DOAGW31, ALRA81	LP83, DOAGW22, GW31	LP83, DOAGW22, GW31
Surface texture	Fine sandy loam	Fine sandy loam	Sandy loam	Fine sandy loam - silty loam	Fine sandy loam - silty loam
Permeability	Moderate	Moderate	Moderate	Moderate to slow	Slow
Depth (m)	0.7	0.7	0.7	0.7-1.4	1.5
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS Critical land features, processes, forms	Friable with better infiltration in moister areas, hardsetting and more prone to sheet and rill erosion in drier areas (north and westerly aspects). Susceptible to acidification in wetter areas.	Friable with better infiltration in moister areas, hardsetting and more prone to sheet and rill erosion in drier areas (north and westerly aspects). Susceptible to acidification in wetter areas.	Soils may be friable with better infiltration in moister areas, hardsetting and more prone to sheet and rill erosion in drier areas (including drier aspects). Sodic subsoil prone to gully and tunnel erosion. Susceptible to acidification in wetter areas.	Soils are friable with better infiltration in moister areas, hardsetting and more prone to sheet and rill erosion in drier areas (including drier aspects). Sodic subsoil prone to gully and tunnel erosion. Susceptible to acidification in wetter areas.	Soils are friable with better infiltration in moister areas, hardsetting and more prone to sheet and rill erosion in drier areas (including drier aspects). Sodic subsoil prone to gully and tunnel erosion. Susceptible to acidification in wetter areas.

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