Soil/Landform Unit 5

Landform Unit Description

The forests west of Lal Lal are mainly Grassy and Heaty Dry Forests. Nearly 80% of this unit comprises significant remnant vegetation	Area: 3546 ha 0.27% of CMA region
	Low hills associated with Ordovician sandstones and shales is a major landform within Ordovician sediments near Lal Lal. This unit has a high level of remnant vegetation (80%) on undulating slopes that have relatively low inherent soil fertility levels. As part of the Western Uplands, this unit is significant for its vegetation within the Central Highlands. Native vegetation classes of these low hills include Valley Grassy, Grassy Dry, Heathy Dry and Herb-rich Foothill Forests as well as Plains Grassy Woodlands. Land use is mainly confined to nature conservation and grazing, however there are some significant hardwood plantations within this unit. Soils include red mottled yellow earths or texture contrast soils on the slopes, shallow stony red gradational soils on crests and black gradational soils on drainage depressions. The main hazards to land use are overland flow causing sheet and rill erosion, and gully erosion where subsoils are exposed. Soils are particularly limited for agricultural land use by their low inherent fertility and water holding capacity.

These low hills support grazing by sheep and beef cattle.
	Plantation forestry is a land use of the Ordovician slopes and crests

Component	1	2	3	4
Proportion of soil-landform unit	2%	48%	3%	47%
CLIMATE Rainfall (mm)	Annual: 720
Temperature (^oC)	Minimum 7, Maximum 17
Precipitation less than potential evapotranspiration	November-March
GEOLOGY Age and lithology	Ordovician marine sandstone and shale, minor Quaternary basalt and Neogene fluvial sand.
Geomorphology	2.1.1 Dissected Western Uplands associated with Palaeozoic sedimentary and metamorphic rocks
LANDUSE	Uncleared: Nature conservation; water supply Cleared: Sheep and beef cattle grazing; softwood plantations; cropping (cereal); water supply
TOPOGRAPHY Landscape	Steep hills
Elevation range (m)	309-538
Local relief (m)	65
Drainage pattern	Dendritic
Drainage density (km/km²)	3.5
Landform	Hills
Landform element	Moist protected slopes	Dry exposed slopes	Drainage lines	Crests
Slope and range (%)	15 (10-32)	15 (10-32)	3 (1-5)	3 (1-6)
Slope shape	Straight	Straight	Concave	Convex
NATIVE VEGETATION Ecological Vegetation Class	Grassy Dry Forest (25.7%, Heathy Dry Forest (22.3%), Valley Grassy Forest (13.6%); Plains Grassy Woodland (5.9%); Herb-rich Foothill Forest (2.4%); other (0.9%)
NATIVE VEGETATION Ecological Vegetation Class
Dominant species	E. obliqua, E. ovata, E. radiata, E. viminalis	E. obliqua, E. dives, E. radiata, E. viminalis	E. ovata, E. radiata, E. viminalis	E. obliqua, E. dives, E. radiata, E. viminalis
SOIL Parent material	In situ weathered sandstone and shale	In situ weathered sandstone and shale	Alluvium, clay, silt, sand, gravel	In situ weathered sandstone and shale
SOIL Parent material	In situ weathered sandstone and shale	In situ weathered sandstone and shale	Alluvium, clay, silt, sand, gravel	In situ weathered sandstone and shale
Description (Corangamite Soil Group)	Red mottled brown, grey or yellow gradational (25) or texture contrast soils, fine structure (26)	Red mottled brown, grey or yellow gradatioal (25) or texture contrast soils, fine structure (26)	Black gradational soil - variable (34)	Shallow stony red (40) and brown, grey or yellow gradational soil (41)
Soil type sites	BD10, CLRA53, BD11	BD10, CLRA53, BD11	CLRA1, SW39, SW57	BD2, SW96, BD3
Surface texture	Fine sandy loam	Fine sandy loam	Clay loam	Gravelly loam
Permeability	High	High	Moderate to low	High
Depth (m)	1	2	>1	0.5
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS	Steep slopes and hardsetting surfaces contribute to overland flow and sheet and rill erosion. Soil compaction also a limiation when soils are waterlogged.	Steep slopes and hardsetting surfaces contribute to overland flow and sheet and rill erosion. Soil compaction also a limitation when soils are waterlogged.	Moderate permeability soils with hardsetting surfaces. Subsoils are dispersible. Overland flow and subsurface flow compound waterlogging and gully erosion. Soil compaction also a limitation when soils are waterlogged.	Moderate slopes with hardsetting surfaces. Overland flow known to increase sheet and rill erosion. Soil compaction also a limitation when soils are waterlogged.

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