Soil/Landform Unit 60

Cleared rolling hills at Lavers Hill

Area:

14 354 ha

1.08% of CMA region

Along the crest of the wettest parts of the Otway Range lies a rolling plain with rounded hills and shallow valleys. This area has one of the highest annual rainfalls in Victoria, averaging almost 2000 mm at Weeaproinah. Prior to settlement late last century, tall open forests of

Eucalyptus regnans

and associated species dominated the landscapes, but now most areas have been cleared for agriculture. Some stands of timber remain and other areas are being regenerated to form climax communities of

E. regnans

. Agricultural uses are dairying, beef cattle grazing and cropping. The cool climate, remoteness and freely drained soils make the area suitable for seed potato production. The perennial nature of many of the creeks and drainage lines gives the area high water catchment values. Conflict also arises between its high scenic appeal as a rural landscape and the conversion of farmland to softwood plantations.

Shallow valley dissection with prominent gully erosion
	Mottled soil ped from the subsoil of the crest and upper slope element

Component	1	2	3
Proportion of soil-landform unit	5%	85%	10%
CLIMATE Rainfall (mm)	Annual: 1550-1950, lowest January (80), highest August (210)
Temperature (^oC)	Annual: 10, lowest July (6), highest February (15)
Seasonal growth limitations	Temperature: less than 10^oC (av.) May-October Precipitation: less than potential evapotranspiration late December - early February
GEOLOGY Age and lithology	Cretaceous fluvio-volcanic sandstone, siltstone and mudstone
Geomorphology	3.1.1 Deeply dissected upland plateau of the Southern Uplands
LANDUSE	Cleared area: Dairy farming; beef cattle grazing; row crops (seed potatoes); water supply Uncleared areas: Softwood forestry, hardwood forestry for sawlogs and pulpwood; nature conservation; passive recreation; water supply
TOPOGRAPHY Landscape	Rolling hills along the crest of the Otway Range
Elevation range (m)	340-560
Local relief (m)	45
Drainage pattern	Dendritic with some tellis and radial areas
Drainage density (km/km²)	3.0
Landform	Hills
Landform element	Slope	Crest and slope	Lower slope and drainage line
Slope and range (%)	12 (2-5)	12 (1-20)	5 (1-8)
Slope shape	Convex	Convex	Concave
NATIVE VEGETATION Structure	Tall open forest	Tall open forest	Tall closed forest
Dominant species	E. regnans, E. obliqua, Acacia melanoxylon	E. regnans, E. obliqua, A. melanoxylong	Nothofagus cunninghamii, A. melanxoylong, E. regnans
SOIL Parent material	Deeply weathered in situ sandstone, siltstone and mudstone	In situ sandstone, siltstone and mudstone	Alluvium and colluvium
Description (Corangamite Soil Group)	Brown friable gradational soils (7)	Brown friable gradational soils (7)	Brown friable gradational soils (7)
Soil type sites	OTR418	COF01, CLRA11, OTR748	OTR428
Surface texture	Loam	Clay loam	Loam
Permeability	High	Moderate	High
Depth (m)	2.0	1.6	>2
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS	High rainfall, high permeability and leaching plus loss of organic matter and soil structure upon disturbance lead to nutrient decline and soil compaction. Steeper slopes may be subseqently prone to sheet erosion.	High rainfall and moderate permeability lead to leaching of nutrients and losses in organic matter and soil structure. Steeper slopes are subsequently prone to sheet erosion. Clay subsoils on steeper slopes are subject to frequent saturation and are prone to landslips.	High seasonal watertables and runoff from surrounding slopes lead to waterlogging and soil compaction.

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