OPR Rail Development – Vegetation and Flora Assessment
In 2005, the DEC surveyed Banded Ironstone Formations (BIF) of the Yilgarn Craton, including areas in
Yalgoo bioregion (south of Yalgoo) (Markey & Dillon, 2008a). One hundred and three quadrats
were established during the survey and one DRF taxon and 13 Priority Flora taxa were
recorded (Table B.1, Appendix B).
Markey & Dillon (2008b) surveyed the flora and vegetation at Weld Range (Murchison
communities (and four sub‐communities) were described. Eight Priority Flora taxa were
recorded (Table B.1, Appendix B).
Caruso (2008). Fifty quadrats were established during the survey and six vegetation
communities were described. Four Priority Flora taxa were recorded (Table B.1, Appendix B).
ecologia (2009a, in preparation) conducted an extensive three phase vegetation and flora
assessment at Weld Range; surveys were completed in 2006, 2007 and 2008. A total of 239 quadrats
were established during the surveys and seven vegetation communities (and 16 sub‐communities)
were described and mapped. Twenty‐four Priority Flora species were recorded (Table B.1, Appendix
During 2004/2005, Mattiske (2005) conducted a flora and vegetation assessment at Jack Hills. One
communities were described and mapped. Four Priority Flora taxa were recorded (Table B.1,
ecologia (2009b, Draft) also conducted a two phase vegetation and flora assessment at Jack Hills in
2006/2007. One‐hundred and ninety‐five quadrats were established during the survey and six
vegetation communities (and 18 sub‐communities) were described. Seven Priority Flora taxa were
A baseline vegetation survey was conducted near Mount Magnet in 1994 by Landcare Services
(1995). Quadrats were assessed at eight sites in native vegetation and one rehabilitated waste dump
site. The dominant vegetation of the area was Acacia aneura woodlands with a mixed understorey
of chenopods and Eremophila species. Of the 206 endemic taxa recorded during the survey, three
were Priority Flora: Alyxia tetanifolia (Priority 3), Calytrix erosipetala (Priority 3) and Grevillea
inconspicua (Priority 4).
Alan Tingay & Associates (1998) completed an environmental appraisal and management plan for a
proposed railway from Tallering Peak to Oakajee. They reported on findings from several vegetation
and flora surveys conducted along the route. Eleven vegetation associations were described and 321
flora taxa were recorded. Twelve Priority Flora taxa were recorded along the route: Scholtzia sp.
Gunyidi (J.D. Briggs 1721) (Priority 2), Scholtzia sp. Murchison River (A.S. George 7098) (Priority 2),
In 1998, Landcare Services Pty Ltd (1998) conducted a flora and fauna survey from Oakajee to south
of Geraldton. Ten vegetation types were described and a total of 117 flora taxa were recorded. Two
Priority Flora species were recorded: Grevillea erinacea (Priority 3) and Stenanthemum divaricatum
Dames & Moore (1993) conducted a flora and fauna assessment at Oakajee in 1993. Six vegetation
Heaths and shrublands dominated the vegetation, with some minor woodland in river valleys. One
hundred and sixty‐five flora taxa were recorded during the survey, including one Priority Flora
species ‐ Grevillea triloba (Priority 3).
In August 1997 Muir Environmental (1977) conducted a follow‐up survey of the area surveyed by
Dames and Moore (1993), as it was extended to include a buffer zone and quarry sites. The
vegetation of the six terrain types identified by Dames and Moore (1993) was re‐assessed. Two‐
hundred and seventeen taxa were recorded (52 more than in 1993). One confirmed DRF and two
Priority Flora taxa were recorded during this survey: Eucalyptus blaxellii (Vulnerable, Priority 4),
Grevillea triloba (Priority 3), and Verticordia penicillaris (Priority 4). The collection of a hybrid
specimen (a cross between Caladenia hoffmanii (DRF) and Caladenia longicauda) indicates that
followed by a threatened flora survey (in 2009) at Oakajee. Twenty‐one quadrats were assessed
during the vegetation and flora survey, and 14 vegetation units were described and mapped at a
scale of 1:40,000. One DRF and 10 Priority Flora were recorded during the surveys (Table B.1,
A biological survey of the Buller River area was conducted by ecologia (2009d, in preparation) in
2009. Five vegetation units at the sub association level were described and mapped. Sixty‐three
flora taxa were recorded, and none of these were DRF or Priority Flora.
An ecological survey was conducted by GHD (2009) for a proposed haul road between Jack Hills and
Weld Range. Twenty‐five quadrats were assessed during the vegetation and flora survey, and 18
vegetation units were described and mapped. Eight Priority Flora taxa were recorded during this
survey (Table B.1, Appendix B).
The Study Area lies predominantly in Beard’s (1976) Murchison region of the Eremaean Botanical
Province. The Murchison region is well known for the dominance of mulga (Acacia aneura)
woodlands, and the extensive flats and plains provide optimum conditions for these woodlands. On
the more favourable soils (plains and valleys) Acacia aneura generally grows in the form of a tree
with a single erect trunk and forms low woodlands. On less favourable soils (hill slopes and ridges) it
takes the form of a shrub producing shrublands/scrublands (Beard, 1976).
Most of the Study Area lies in the Upper Murchison subregion in the Murchison region of the
Eremaean Botanical Province (Beard, 1976). The vegetation of this area is described as:
deterioration and death is common in this area, and there is very little regeneration of the A.
or other Acacia species such as A. victoriae and A. tetragonophylla.
Granite and gneiss hills are generally covered with Acacia aneura (shrub form), and A.
species include Eremophila spathulata and Ptilotus obovatus. The main species at Jack Hills is
support two main species – Acacia aneura and Acacia quadrimarginea – additional species
include Eremophila latrobei, Scaevola spinescens and Ptilotus obovatus. The lower slopes are
covered with Acacia aneura and A. ramulosa var. linophylla.
Sandplain patches consist of Acacia ramulosa var. linophylla scrub, with A. aneura less
commonly. While Eremophila leucophylla, Solanum lasiophyllum and Maireana convexa occur
as understorey shrubs.
Extensive salt flats, along the upper courses of the Murchison, are covered with Atriplex
Downstream of the Murchison, the main vegetation is Acacia species scrub (A. victoriae, A.
A section of the Study Area is situated in the Yalgoo subregion in the Murchison region of the
Eremaean Botanical Province (Beard, 1976). The vegetation associated with this transitional area,
between the Eremaean Botanical Province and the South‐western Botanical Province, is described as:
Still Eremaean in character, but with the increase in rainfall and the shift of climate from
species. The vegetation also becomes lower and denser in a south‐westerly direction.
The plains of the inland portion of this subregion support mixed Acacia species scrub mainly of
scrub, with A. quadrimarginea and A. stereophylla. The sandplains have a rich flora and are
dominated by Acacia ramulosa var. ramulosa and A. murrayana. Low‐lying plains support
Acacia sclerosperma and A. eremaea scrub, with Atriplex and Maireana species.
A small section of the Study Area incorporates the Talisker vegetation system of the Eremaean
Botanical Province. The vegetation of this system is described by Beard & Burns (1976) as:
Sandplain associated with Acacia ramulosa var. ramulosa/Acacia ramulosa var. linophylla
The remaining section lies in the Greenough region of the South‐western Botanical Province,
incorporating the Yuna, Kalbarri, Northampton, Greenough and Mullewa vegetation systems (Beard,
1976; Beard & Burns, 1976). The vegetation of these systems is described as:
Yuna System: the yellow sandplains support scrub heath associations; Acacia‐Casuarina
red soil depressions. Eucalyptus loxophleba and E. loxophleba‐E. salmonophloia woodlands
occur in bottomland soils west of Mullewa. The Greenough River valley is generally covered
with Acacia acuminata scrub and scattered Eucalyptus loxophleba. Salt flat vegetation is
primarily Tecticornia species and other samphires, with some Atriplex vesicaria and Melaleuca
covers most of the area ‐ Acacia rostellifera occurs near the coast, Adenanthos cygnorum,
include Eucalyptus loxophleba, E. eudesmioides and E. dongarraensis.
Northampton System: scrub heath associations occur on mesa tops (laterite and sand); laterite
Dryandra spp., Calothamnus spp., Hakea spp. and Melaleuca spp.; while the sand community
grows taller and more open with Acacia rostellifera, Banksia, Dryandra, Casuarina and
Gastrolobium species. Melaleuca‐Hakea spp. thickets occur on the Jurassic sediments
(generally forming steep scarp slopes) and the two dominant communities are Melaleuca
undulating terrain on granites and granulites, while Allocasuarina campestris thickets occur on
gravelly soils and scattered Eucalyptus camaldulensis along drainage lines.
thickets. Acacia‐Banksia species scrub (dominated by Acacia rostellifera and Banksia
alluvial flats, recent dunes commonly support Acacia ligulata open scrub, while Eucalyptus
vegetation of the dissected terrain is Acacia acuminata scrub with scattered Eucalyptus
ephemerals comprising the ground layer.
The vegetation of the Study Area was mapped as 28 communities by Beard (1976) and Beard & Burns
(1976). These 28 units are described in Table 2.8 and shown in Figure 2.12 to Figure 2.16.
Acacia aneura, Acacia ramulosa var. ramulosa and Acacia ramulosa var. linophylla low
spp. succulent steppe.
Acacia quadrimarginea scrub.
Acacia aneura low woodland with understorey of Acacia ramulosa var. ramulosa,
Acacia ramulosa var. linophylla and Acacia grasbyi.
Mixed Acacia spp. scrub.
Acacia ramulosa var. ramulosa and Acacia ramulosa var. linophylla scrub with Callitris
columellaris and Eucalyptus spp.
scrub with scattered Eucalyptus loxophleba and Casuarina huegeliana.
Eucalyptus loxophleba and Eucalyptus salmonophloia sclerophyll woodland.
Scrub heath coastal association.
Scrub heath inland association.
Acacia ‐ Casuarina spp. thicket with scrub heath inland association.
‘Beard Code’ column refers to vegetation types mapped by Beard (1976) and Beard & Burns (1976).
Proposed Rail Alignment
Proposed Project Area
Name: GDA 1994 MGA Zone 50
Projection: Transverse Mercator
Datum: GDA 1994
Unique Map ID: A014