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Eucalyptus leptophleba (Mollow Red Box) on sandy undulating plains or river levees.
Eucalyptus megasepala (Messmate) on sandstone ridges and outcrops and
undulating sandy plains.
SLATS data for Cape York in general from the 1980‟s to present (Queensland Department of
Environment and Resource Management (QDERM) 2009) indicate that forest clearing by
man has been relatively low compared to the rest of the state. This is especially true for
Oriners and Sefton Stations. However local tree clearing has been conducted around the
homesteads and yards, and more recently by large scale clearing along roadways for major
upgrade and development purposes (Figure 41; Figure 74).
3.3.2 Grass cover
Grass cover, community types, and dominant grass species distributions have been mapped
for the area around Oriners and Sefton Stations by government programs such as CYPLUS
(Neldner and Clarkson 1995; Clarkson and Neldner 1995 in prep; Neldner and Clarkson
1995 in prep; Neldner, Stanton et al. 1997; Clarkson 2009) and more recent vegetation
mapping by the Queensland Herbarium. A grass species list was also obtained for the area
(Appendix, Section 8.4) using DERM‟s Wildlife Online Database. A brief summary of the
main grassland conditions of Oriners and Sefton Stations is provided below, but this needs to
be updated with the latest mapping and data from the Queensland Government.
Around Oriners and Sefton Stations, Neldner and Clarkson (1995) mapped the grassland of
Oriners and Sefton Stations as tussock grasslands on longitudinal drainage depressions
(BVG 23). Neldner et al (1997) refined the maps of the grassland communities across the
Holroyd Plain (map unit 180) and described the grasslands as either dominant or
subdominant in comparison to other vegetation communities like woodland trees. Both exist
in the area. The subdominant grasslands coexist beneath woodland tree canopies. The
dominant pure grasslands at Oriners are located the Aerodrome Plain extending downstream
along Eight-Mile Creek and Crosby Creek to the Alice River. The dominant grassland
communities are tussock to closed-tussock grasslands (0.2 to 0.6 m tall) with the following
plant genera:
Eriachne spp. (wanderrie grass)
Aristida spp. (three-awned speargrass)
Eragrostis spp. (lovegrass)
Fimbristylis spp. (sedge)
Typically Eriachne burkittii and Eriachne obtusa (Wanderrie) dominate the pure grasslands,
while scattered trees of Melaleuca viridiflora (broad leaved ti tree) are also common.
Eriachne spp. (Wanderrie) can be short-lived annuals or perennials, whereas Aristida spp.,
Eragrostis spp, and Fimbristylis spp. are typically perennial. Neldner et al (1997) described
the ecology of these grasslands across the Holroyd Plain (unit 180) as occurring “extensively
in the longitudinal drainage depressions [dambos],… [where] sites are waterlogged for much
of the wet season, and receive water seepage from the adjacent sand ridges in the early dry
season. They dry out very rapidly after seepage ceases and the predominantly ephemeral
herbs complete their life cycle and die. The soils are predominantly Sodosolic or Dermosolic
Redoxic Hydrosols”.
3.3.3 Weeds
Over the last 60 years of European settlement in the Oriners and Sefton area, low levels of
human presence and through traffic have kept Oriners mostly weed-free compared to other
sections of Cape York. However, introduced plants are present in the area, and have been
increasing over the last decade according to local observation. Some species like Mintweed
(Hyptis suaveolens) and Noogoora burr (Xanthium occidentale), have been slowly invading
over decades. Others destructive invaders such as Rubber vine (Cyptostegia grandiflora) are
widespread along the Mitchell River mainstem, but not currently present on Oriners and
Sefton Stations. Other relatively new and very aggressive weed species have been identified
Working Knowledge at Oriners Station, Cape York
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