Soil/Landform Unit 143

Dissected residual granitic slopes of the Lismore Granodiorite

Area:

4530 ha

0.34% of CMA region

This unit of undulating low hills is derived from residual granitic outcrops on the Western Plains. This single unit lying north-east of Lismore near Wallinduc, consists of granitic outcrop with a partially remaining veneer of Neogene (colluvial) sedimentary material. Unit components include rocky and sandy crests, upper, mid and lower slopes. This unit is surrounded by basaltic plains (Units

136

and

117

) and a small sedimentary area (Unit

172

). The soils are uniform sands (

Tenosols

) or sands over clay on the upper slopes, while strongly

sodic

mottled

brown, grey and yellow texture contrast soils (

Sodosols

) are found on the mid and lower slopes. Land use is mainly grazing (sheep). The sloping terrain in conjunction with loose sandy surface soils means this unit is susceptible to sheet and rill erosion and nutrient decline. It is also susceptible to gully erosion on the lower slopes with the strongly sodic subsoils and coarse sand fraction.

Mont Kinross, south-east of Pitfield

Component	1	2	3
Proportion of soil-landform unit	15%	30%	55%
CLIMATE Rainfall (mm)	Annual: 620
Temperature (^oC)	Minimum 8, Maximum 19
Precipitation less than potential evapotranspiration	October-March
GEOLOGY Age and lithology	Quaternary basalt, Devonian granite and Neogene fluvio-marine sand
Geomorphology	6.3.1 Granitic hills (e.g. Mount Kinross) and 6.1.4 Volcanic Western Plains with well developed drainage
LANDUSE	Uncleared areas: Nature conservation Cleared areas: Sheep and beef cattle grazing; cropping (cereal)
TOPOGRAPHY Landscape	Undulating low granodiorite hills and rises
Elevation range (m)	150-274
Local relief (m)	60
Drainage pattern	Centripetal
Drainage density (km/km²)	1.5
Landform	Hillslopes
Landform element	Rocky crests and upper slopes	Mid slopes	Lower slopes
Slope and range (%)	4 (1-9)	6 (3-12)	3 (1-8)
Slope shape	Convex	Convex	Concave
NATIVE VEGETATION Ecological Vegetation Class	Plains Grassland / Plains Grassy Woodland Mosaic (1.0%), Grassy Woodland (0.4%)
SOIL Parent material	Granodiorite	Granodiorite	Granodiorite and colluvium
Description (Corangamite Soil Group)	Neutral mottled brown, grey or yellow texture contrast soils (4)	Sodic mottled brown, grey or yellow texture contrast soils (1)	Sodic mottled brown, grey or yellow texture contrast soils (1)
Soil type sites	BD8, MM236	BD7, MM436, MM237	BD7, MM436, MM237
Surface texture	Loamy sand	Sandy loam	Sandy clay loam
Permeability	High to very high	High	Moderate to low
Depth (m)	<1.5	<2	>2
LAND CHARACTERISTICS, POTENTIAL AND LIMITATIONS	Texture contrast with deep sandy surface and subsurface soils of uniform sands. Very low water holding capcity and nutrient holding capacity in upper soil, high in clay subsoil. Sandy surface and subsurface soils, loose consistence, susceptible to nutrient decline and sheet and rill erosion. Moderate rapid site drainage.	Texture contrast with deep sandy surface and subsurface soils of uniform sands. Very low water holding capacity and nutrient holding capacity in upper soil, higher in strongly sodic clay subsoil. Sandy surface and subsurface soils, loose consistence, susceptible to nutrient decline and sheet and rill erosion. Moderately rapid site drainage.	Large texture contrast with sandy surface soil and subsurface soils. Very low water holding capacity and nutrient holding capacity in upper soil, higher in strongly sodic clay subsoil. Sandy surface and subsurface soils, loose or hardsetting consistence. Susceptible to nutrient decline and sheet and rill erosion, possible tunnel and gully erosion. Permeability high in upper soil, low in subsoil. Moderate site drainage.

Page top