Obbens & Sage: Vegetation and flora of an upland remnant. Western Australian wheatbelt 
Figure 2. Map of vegetation communities of A21064 Nature Reserve that include 1 and la Open Woodland, 2 and 2a Low Woodland, 3 
Low Forest, 4 Woodland, 5 and 5a Heath, 6 Low Heath, 7 Thicket (Tall Heath), 8 Herbfield, 9 and 9a Mallet Woodland, 10 Mallee 
Woodland and G Rehabilitated gravel pits. Communities are described below. 
1 Open Woodland . Dominated by Eucalyptus zvandoo with 
a generally very open, but variable understorey. This 
includes areas of almost pure Gastrolobium trilobum or 
Melaleuca aff uncinata or 'parkland-like' areas with 
numerous orchids/annuaIs/grasses and smaller shrubs. 
Many trees are large to 25 m high with a canopy density 
about 5 - 15% (i.e. very sparse to sparse). Soils are either 
grey coarse sandy loams or, at the reserve's western end, 
brown coarse loams with some lateritic gravels. This 
community represents the top end of shallow drainage 
lines that form defined creeks further down slope outside 
the reserve boundaries. 
la Open Woodland . A variant of above, again, dominated 
by Eucalyptus zvandoo of generally smaller stature and with 
a denser canopy cover, about 10 - 25% (i.e. sparse). Lying 
entirely on lateritic ridge country, it demarcates itself from 
community 1 along the line of a small breakaway. A 
sparse to mid dense understorey of predominately 
Dryandra species occur on exposed lateritic boulders with 
residual soils on the top edge of the breakaway and up 
slope at the ridgeline. Elsewhere is fairly open with 
various scattered shrubs and some annuals on soils of red- 
brown clay loam with numerous gravels. 
2 Low Woodland . A mixed woodland with a mid dense 
canopy cover (i.e. about 30 - 70%) consisting of almost 
equal proportions of Eucalyptus zvandoo (up to 20 m high) 
and Allocasuarina huegeliam on grey-brown sandy loams 
sometimes with varying amounts of gravel. Understorey 
is variable including open areas of low shrubs, annuals 
and some grasses to mid dense areas of Acacia or 
Gastrolobium. 
2a Low Woodland . A mixed woodland variant of above 
with mid dense canopy consisting of Eucalyptus zvandoo 
(up to 20 m high) and interspersed individuals or patches 
of Eucalyptus astringens subsp astringens (Brown Mallet) 
and occasionally with scattered Allocasuarina huegeliam. 
Again, a variable understorey ranging mostly open to 
mid dense in parts. Soils are red-brown coarse clay loams 
with gravels and sometimes there is exposed lateritic 
hardcap. 
3 Low Forest . Predominantly pure stands of Allocasuarina 
huegeliam with occasional scattered Eucalyptus zvandoo 
and generally mid dense to dense canopy cover (i.e. > 
70%). Soils are grey-brown to red-brown sandy or clayey 
sand loams sometimes with a little gravel. The 
understorey canopy cover is open to mid dense, 
including numerous annuals and commonly a tall 
Lepidosperma sp (FO204/98), Agrostocrinum scabrum and 
Hypocalymma angustifolium. This community occurs 
where granite is close to the surface and often 
outcropping or boulder stacks are nearby. 
4 Woodland . Composed of pure stands of tall (i.e. 25 - 30 
m) Eucalyptus longicornis with a very sparse understorey 
of Acacia erinacea, Acacia lasiocarpa var. sedifolia, a few 
sedges and annuals found on red-brown clay loams. 
These areas appear to be associated with shallow 
drainage zones. 
5 Heath . A heath of mid dense to dense canopy cover 
containing a diverse mix of shrubs about 1 - 2 m high on 
grey-brown sandy clay loams with some gravel content. 
The families Myrtaceae, Proteaceae, Goodeniaceae, 
Papilionaceae and Stylidiaceae are well represented along 
with many others. This community occurs on the gentle 
mid slope areas of the reserve and never appears on the 
ridge top. 
5a Heath . A variant of the above comprising a diverse 
mix of shrubs (about 1 - 2 m) with interspersed emergent 
shrubs (to about 3.5 m) namely Dryandra sessilis and 
Nuytsia floribunda. This unusual combination occurs on a 
localised sheet of white sand, which probably overlays 
lateritic and/or granitic profiles seen adjacent to this 
community. Eremaea pauciflora dominates although many 
other species are present. 
6 Low Heath . A very diverse mix of small to mid sized 
shrubs (about 0.25 - 1.5 m) with a mid dense canopy 
cover found on white-grey clayey loams with occasional 
gravel content. This soil profile is possibly exposed and 
eroding kaolin, and occurs extensively on lower parts of 
the flattened ridgeline. This community contains the 
same families as outlined for community 5; however, it 
also has a marginally greater diversity of taxa than the 
above heaths. 
21 
