Your gateway to a wide range of natural resources information and associated maps

Victorian Resources Online

EGC212

Location: Benambra

Australian Soil Classification: Bleached, Eutrophic, Red KANDOSOL

Map Unit: Cobungra (Component 1)
Previous Site Name: EG212

General Landscape Description: Rounded low hills
Site Description: Upper north facing slope (5% slope)
Land Use: Grazing on annual pasture
Native Vegetation: Montane grassy woodland and herb rich woodland
Geology: Palaeozoic granite


Soils and landforms of the Omeo/Benambra and Tambo Valley region - soil-landform unit Cobungra EG212 landscape



Soil Profile Morphology:

Surface soil

Soils and landforms of the Omeo/Benambra and Tambo Valley region - soil-landform unit Cobungra EG212 profile
A10 – 15 cmDark brown (10YR4/3); coarsesandy loam; weak medium (10 – 20 mm) granular structure; very weak consistence dry; pH 5.1; clear change to:
A2115 – 35 cmLight brown (7.5YR6/4), conspicuously beached (7.5YR7/2d); coarse sandy loam; apedal; very weak consistence dry; pH 5.3; diffuse change to:
A2235 – 60 cmBrown (7.5YR5/4); coarse sandy loam; apedal; weak consistence dry; pH 6.2; clear change to:
Subsoil

B2160 – 100 cmYellowish red (5YR5/6); sandy clay loam; apedal; firm consistence dry; pH 6.6; diffuse change to:
B22100 – 110 cmYellowish red (5YR5/6) with white flecks of feldspar; clayey sand; apedal; firm consistence dry

Key Profile Features:
  • Lack of a marked texture contrast between the surface (A) horizon and the subsoil (B) horizon.
  • The sandy and hard setting nature of the soil profile.

Soil Profile Characteristics:
-

pH
Salinity
Surface soil
(A1 horizon)
Strongly Acid
Very Low
Non-sodic
None
Subsurface soil
(A21 horizon)
Strongly Acid
Very Low
Non-sodic
Slight
Deeper subsoil
(B21 horizon)
Slightly Acid
Very Low
Non-sodic
None


Chemical and Physical Analysis:


Horizon
Horizon Depth
(cm)
pH
(water)
EC
dS/m
Organic Carbon
%
Total
Nitrogen
%
Exchangeable Aluminium
ppm
Exchangeable Acididty
meq/100g
Exchangeable Cations
Coarse Sand
(0.2-2.0 mm)
%
Fine Sand
(0.02-0.2 mm)
%
Silt
(0.002-0.02 mm)
%
Clay
(<0.002 mm)
%
Field Capacity
% w/w
Wilting Point
% w/w
Ca
Mg
K
Na
meq/100g
A1
0-15
5.1
0.08
2.2
0.12
20
7.2
2.5
0.4
0.4
<0.05
40
34
12
8
23.1
4.9
A21
15-35
5.3
<0.05
0.56
<0.05
19
2.1
0.84
0.13
0.16
<0.05
37
36
11
13
16.6
2.3
A22
35-60
6.2
<0.05
0.39
1.3
1.2
0.19
0.11
<0.05
43
31
12
13
14.2
2.5
B21
60-110
6.6
<0.05
0.3
1.2
4
1.7
0.27
0.07
39
26
11
20
29.0
9.7


Management Considerations

Whole profile
  • Plant available water is considered to be very low. Effective rooting depth is largely confined to the surface 25 cm because of the dense and hard-setting nature of the soil below this layer.
  • The deep subsoil slakes considerably when wet and, as a result, would be prone to tunnel and gully erosion in the wetter parts of the landscape.
  • The soil has good external and internal drainage and is not likely to become waterlogged during wetter periods.
Surface (A) horizons
  • The surface soil is strongly acid. However the level of exchangeable aluminium is reasonably low (20 mg/kg) and is unlikely to affect the growth of aluminium sensitive species, except the most sensitive. Lime can be used to increase soil pH but a pH/aluminium test is best performed by taking samples across the paddock and bulked together. The use of test strips to observe lime response could be used as an aid in evaluating its cost/benefit. For this soil a response to lime (about 1-2 tonnes/ha) would be expected.
  • Potassium levels are moderate and plant responses to potassium fertiliser are unlikely given the present grazing management practices.
  • Salinity is not a problem in the surface soil.
  • Deficiencies of molybdenum and phosphorus may occur in the strongly acid surface soils and increasing the pH by lime application should enable the phosphorus (from superphosphate) and molybdenum to become more available.
  • The nutrient holding capacity of the surface (A1 and A21) horizons is very low (based on the sum of the exchangeable calcium, magnesium, potassium and sodium cations).
Subsoil (B) horizons
  • Root growth would be severely restricted because of the dense and hard nature.
  • The deep subsoil slakes considerably when wet, making it prone to tunnel and gully erosion.


Soil Profile Described By: Heather Adams, Julieanne Sargant and Ian Sargeant, June 2009.
Page top