Cunninghamia : A Journal of Plant Ecology for Eastern Australia, Volume 6, Issue 2 (1999)
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The species Sarcochilus dilatatus F. Muell. is an Australian endemic orchid, recorded in south-eastern Queensland and the upper north-east of New South Wales (NSW), between the Kroombit Tops (Calliope Range — inland from Gladstone) Queensland (Walsh 1997) and the Richmond River New South Wales (Jones 1988). The species occurs along the coast and lower ranges, up to 400 m altitude (Weston 1993) where it is epiphytic. It appears to favour Araucaria cunninghamii (Hoop Pine) above all other hosts, and germinates on smaller stems about 8–12 mm diameter, which are in the higher, brighter parts of the crown. The largest population of the species I have seen, south-west of Bundaberg, Queensland, was within a plantation of Hoop Pine, a "habitat" which Walsh (1997) also considers extremely rich in this otherwise rare species.
Identification of Sarcochilus dilatatus requires flowers for confirmation, although the foliage is also quite distinctively marked. A net-like pattern of reddish rectangles occurs across the foliage, with a background colour of green. Often this network pattern is only visible when light is transmitted through the foliage. Leaves on most individuals are few, falcate, and borne on a short stem. The roots are long and slender, mainly white, although older roots will be grey. The inflorescences are axillary, generally pendent, and mostly only one is produced from each axil at any one time, although the axil may produce a number of inflorescences in successive years. Older, larger plants may have a number of inflorescences concurrently (the confirmation specimen was carrying three racemes), but the most common situation is for only one or two racemes per plant. The flowers are small, star-shaped, mainly brown or brownmarked on a greenish background, and have a white labellum variously marked with orange. The tepals are distinctly spathulate.
The first collections of Eucalyptus cannonii were made by R.T. Baker in 1892, during collecting trips to the Rylstone and Goulburn River areas. Although Baker (1896) made numerous notes on many of the plants collected at that time, he made no remarks on the variation in Eucalyptus macrorhyncha (which then included Eucalyptus cannonii) despite claiming so in his later description of the taxon (Baker 1919).
Recognition of the variation shown in what was to become Eucalyptus cannonii was given by Maiden (1907) in his "Critical revision of the genus Eucalyptus" (as Eucalyptus macrorhyncha "grandiflora" form). Maiden highlighted the collections made by Baker from Rylstone and Mt Vincent as being coarser in form with a very prominent rim.
Baker (1919) described this taxon as Eucalyptus cannonii, named after Herbarium assistant Mr D. Cannon. Despite Maiden's comments, Baker (1919) indicated that data presented to him by Mr G. Harris (collector of the material cited by Baker) convinced him of the distinctiveness of the taxon. Eucalyptus cannonii was separated from Eucalyptus macrorhyncha on the shape of the fruit, buds, inflorescence and features of the timber and bark.
Penfold and Willis (1961) considered Eucalyptus cannonii to be distinctive local race of E. macrorhyncha and Johnson and Blaxell (1973) reduced E. cannonii to a subspecies of E. macrorhyncha, based on the intergradation where their ranges overlap. Hill (1991) retained specific status for Eucalyptus cannonii.
The vegetation of Kwiambal National Park and surrounds, 30 km north-west of Ashford (29°07'S, 150°58'E) in the Inverell Shire on the North Western Slopes, is described. Eight plant communities are defined based on flexible UPGMA analysis of relative abundance scores of vascular plant taxa. These communities are mapped based on ground truthing, air photo interpretation and geological substrate. All communities are of woodland structure and most are dominated by Callitris glaucophylla, Eucalyptus melanophloia and Eucalyptus dealbata. Communities are: 1) Mixed Stand Woodland (Dry Rainforest), 2) Granite Woodland, 3) Metasediment Woodland, 4) Riverine, 5) Metabasalt Woodland, 6) Granite Open Woodland, 7) Limestone Woodland, and 8) Alluvial Woodland.
Many of the taxa (407 species were recorded) show phytogeographic affinities with western south-east Queensland flora. This is also true of the communities defined. Five ROTAP listed species have been found in the Park: Acacia williamsiana, Astrotricha roddii, Euphorbia sarcostemmoides, Olearia gravis and Thesium australe, three of these are listed on the NSW Threatened Species Conservation Act (1995). Another ten taxa are considered to be at their geographic limit or disjunct in their distribution. 17% are exotic in origin.
A floristic survey of 40 x 0.1 ha plots within the Demon Nature Reserve, 30 km east-south-east (lat. 29°05'S, long 152°15'E) of Tenterfield, was conducted in March, 1997. The Reserve (887 hectares in area) is on a western facing escarpment ranging from 500–1000 m above sea level. The survey data were analysed and seven vegetation communities defined. This paper describes the seven communities and discusses their significance and distribution within the reserve. A vegetation map and plant species list are provided.
Gladiolus gueinzii (Iridaceae) and Trachyandra divaricata (Liliaceae s.l.) are South African dune plants naturalised in Australia. Gladiolus gueinzii has two modes of dispersal: winged seeds, and cormels that may float for up to seven months in seawater. Its Australian occurrences are restricted to New South Wales. It was first collected in 1950 near Newcastle and has spread 250 km to the north and 500 km to the south. From large distances between the early herbarium records it was inferred that buoyancy of the cormels enables Gladiolus gueinzii to establish at sites remote from existing populations. The climatic conditions of the area over which Gladiolus gueinzii presently occurs are broadly similar to those of the more humid part of its native range. Further spread may be restricted due to unfavourable thermal factors.
Trachyandra divaricata is a "tumbleweed". Wind dislodges and carries away the "crowns" of tangled mature infructescences, in the process peppering their trails with innumerable small seeds. In the 1930s Trachyandra divaricata became established near Perth, Western Australia, while in 1940 it was also found near Karridale, 300 km further south. In the intervening area it has become a major weed in the dunes and has spread to paddocks inland, causing poisoning of livestock. Trachyandra divaricata has also turned up at several other outlying coastal locations as well as at an inland site. The distances involved are suggestive of dispersal by human agency, for instance through cars or boats. The Mediterranean and adjacent semi-arid climates of the south-west of Western Australia mirror a similar situation in southern Africa. Hence, the area appears to be well suited to Trachyandra divaricata and further spread can be expected.
In New South Wales Trachyandra divaricata was first found in 1968 at a dune rehabilitation site near Wollongong. It possibly came in as a contaminant of Acacia saligna planting stock from Western Australia. Since then it has become established at several other reclaimed areas, but has not spread much beyond such sites, possibly because of unfavourable climatic conditions. Nevertheless, in case aggressiveness takes a turn for the worse, it would appear desirable to eradicate occurrences in New South Wales while this is still achievable.
During recent surveys within north-eastern New South Wales new records of range extensions for some significant plant taxa were recorded. The implications for the conservation status of each taxon in terms of their ROTAP status (Briggs & Leigh 1996) are discussed. It is important that management decisions concerning rare taxa are made using the most up-to-date information possible, hence the need to report new distributions and suggest changes in conservation status. Vouchers of all taxa discussed have been lodged at the NCW Beadle Herbarium at the Division of Botany, University of New England and/or at the Herbarium of the North Coast Regional Botanic Garden, Coffs Harbour. In the following notes National Park is abbreviated to NP and Nature Reserve to NR.
A presence/absence survey of 25 remnant vegetation sites, principally Nature Reserves and State Forests, was carried out in the South Western Slopes (SWS) of New South Wales. A total of 658 taxa were recorded of which 188 (29%) were exotics. Eleven sites had an overstorey dominated by Callitris glaucophylla or Eucalyptus camaldulensis and 14 sites had an overstorey dominated by various eucalypt species such as Eucalyptus blakelyi, Eucalyptus goniocalyx, Eucalyptus macrorhyncha, Eucalyptus polyanthemos, Eucalyptus rossii and Eucalyptus sideroxylon. The Callitris glaucophylla/Eucalyptus camaldulensis dominated sites were in the western half of the region, were flatter and at lower elevation (average minimum and maximum elevations were 191 and 214 m, respectively), were smaller (average area 646 ha), were usually grazed more intensely, had a smaller average number of species per site (151) and a larger average percentage of introduced species (40%). In contrast, the sites dominated by various eucalypt species were usually in the eastern half of the region, had greater relief and were at higher elevation (average minimum and maximum elevations were 294 and 520 m, respectively), were larger (average area 1161 ha), were usually grazed less intensively, had a larger average number of species per site (179) and a smaller average percentage of introduced species (27%). This study provides the first published set of relatively comprehensive species lists for the SWS and has provided information relevant to species distribution, proportion of introduced species in the flora, threatened species, areas of conservation significance and directions for future research.
Ecological data in tabular form are provided on 149 plant species of the families Nyctaginaceae to Primulaceae, 75 native and 74 exotics, occurring in the Sydney region, defined by the Central Coast and Central Tablelands botanical subdivisions of New South Wales (approximately bounded by Lake Macquarie, Orange, Crookwell and Nowra). Relevant Local Government Areas are Auburn, Ashfield, Bankstown, Bathurst, Baulkham Hills, Blacktown, Blayney, Blue Mountains, Botany, Burwood, Cabonne, Camden, Campbelltown, Canterbury, Cessnock, Concord, Crookwell, Drummoyne, Evans, Fairfield, Greater Lithgow, Gosford, Hawkesbury, Holroyd, Hornsby, Hunters Hill, Hurstville, Kiama, Kogarah, Ku-Ring-Gai, Lake Macquarie, Lane Cove, Leichhardt, Liverpool, Manly, Marrickville, Mosman, Mulwaree, North Sydney, Oberon, Orange, Parramatta, Penrith, Pittwater, Randwick, Rockdale, Ryde, Rylstone, Shellharbour, Shoalhaven, Singleton, South Sydney, Strathfield, Sutherland, Sydney City, Warringah, Waverley, Willoughby, Wingecarribee, Wollondilly, Wollongong, Woollahra and Wyong.
Families are: Nyctaginaceae, Nymphaeaceae, Ochnaceae, Olacaceae, Oleaceae, Onagraceae, Oxalidaceae, Papaveraceae, Passifloraceae, Peperomiaceae, Piperaceae, Pittosporaceae, Plantaginaceae, Plumbaginaceae, Polemoniaceae, Polygalaceae, Polygonaceae, Portulacaceae, Primulaceae.
Data are derived from herbarium collections, literature and field observations. It is hoped that the many, often alarming gaps in the information available will stimulate much-needed research into the ecology of more of the species. Information is provided so far as available to us for each plant species in the following categories:
Life History: Growth form, vegetative spread, longevity, primary juvenile period (time from germination to fruiting), reproduction, flowering and fruiting times, fruit/seed type, dispersal, establishment and growth, fire response, interaction with other organisms.
Distribution: Status/origin (native/naturalised), botanical subregions, distribution in Sydney area, selected locations.
Habitat: Habitat, altitude, annual rainfall, typical local abundance, vegetation, substrate, exposure.
Conservation: Conservation status.
This work indicates that Bothriochloa biloba shows a strong preference for heavier-textured soils. On these soils the species, despite its known poor seed production, has been maintained under grazing over long periods of time. It is concluded that normal levels of grazing do not lead to elimination of Bothriochloa biloba, and in fact may enhance maintenance of the species. By contrast, at restricted levels of grazing, rank growth of Aristida ramosa causes reduction in total number of species and exclusion of Bothriochloa biloba. In grasslands grazed at an unrestricted level, stock selectively grazed other species of grass, giving Bothriochloa biloba a competitive advantage. Mowing and/or slashing also appeared to maintain the species.