Regional ecosystem details for 11.9.5
| Regional ecosystem | 11.9.5 |
|---|---|
| Vegetation Management Act class | Endangered |
| Wetlands | Not a Wetland |
| Biodiversity status | Endangered |
| Subregion | 26, 15, 25, 20, 21, 27, 6, (24), (33), (32), (31), (11), (29), (23), (10), (28), (22), (19), (2), (34), (6.2), (16), (6.1), (12), (18), (9), (7), (36) |
| Estimated extent1 | Pre-clearing 2276000 ha; Remnant 2021 161000 ha |
| Short description | Acacia harpophylla and/or Casuarina cristata open forest to woodland on fine-grained sedimentary rocks |
| Structure code | Open Forest |
| Description | Acacia harpophylla and/or Casuarina cristata or Acacia harpophylla open forest to woodland. Casuarina cristata is more common in southern parts of the bioregion. A prominent low tree or tall shrub layer dominated by species such as Geijera parviflora and Eremophila mitchellii, and occasionally with semi-evergreen vine thicket species is often present. The latter include Flindersia dissosperma, Brachychiton rupestris, Excoecaria dallachyana, Macropteranthes leichhardtii and Acalypha eremorum in eastern areas, and species such as Carissa ovata, Owenia acidula, Croton insularis, Denhamia oleaster and Notelaea microcarpa in south-western areas. Melaleuca bracteata may be present along watercourses. Occurs on fine-grained sediments. The topography includes gently undulating plains, valley floors and undulating footslopes and rarely on low hills. The soils are generally deep texture-contrast and cracking clays. The cracking clays are usually black or grey to brown or reddish-brown in colour, often self-mulching and sometimes with gilgai microrelief in flatter areas. Some texture contrast soils are shallow to only moderately deep. Not a Wetland. (BVG1M: 25a). Vegetation communities in this regional ecosystem include: 11.9.5a: Acacia harpophylla predominates and forms a fairly continuous canopy (10-18m high). Other tree species such as Eucalyptus populnea, Casuarina cristata, Cadellia pentastylis and Brachychiton spp. may also be present in some areas and form part of the canopy or emerge above it. Scattered Eucalyptus orgadophila may occur, especially on upper slopes and crests. A dense tall shrub layer dominated by a range of species is usually present, while a more open low shrub layer often occurs. Common species in these layers include Croton insularis, Denhamia oleaster, Capparis anomala, Croton phebalioides, Alectryon diversifolius and Carissa ovata. The ground layer is sparse, most frequently composed of Ancistrachne uncinulata and Eragrostis megalosperma and varies with the density of the shrub layers. Occurs on undulating plains and rises formed mainly on shales. The soils are predominantly cracking clay soils, which are strongly alkaline at or near the surface and acidic beneath, or dark brown and grey-brown gradational soils, with a coarse-textured surface grading into an alkaline, clayey subsoil. Not a Wetland. (BVG1M: 25a). |
| Supplementary description | Dawson (1972), Ulimaroa (1-3); Galloway et al. (1974), LU 38, 40, (41), 43, 44; Gunn and Nix (1977), LU 34, 37, 38, 41, 46, 50, 53, 72, 75, 93, 100, 101; Gunn et al. (1967), Craven (4), Cungelella (1,3), Hillalong (3), Kareela (4), Rutland (4), Skye (4), |
| Protected areas | Carnarvon NP, Palmgrove NP (S), Expedition (Limited Depth) NP, Tregole NP, Chesterton Range NP, Isla Gorge NP, Precipice NP, Roundstone CP, Homevale NP, Taunton NP (S), Lake Murphy CP, Nuga Nuga NP, Carraba CP, Irongate CP, Homevale RR, Expedition NP, Bun |
| Special values | 11.9.5: Habitat for threatened fauna species including Jalmenus eubulus, pale imperial hairstreak butterfly (Eastwood et al. 2008). |
| Fire management guidelines | INTERVAL: Fire return interval not relevant. INTERVAL_MIN: 100. INTERVAL_MAX: 100. STRATEGY: Maintain fire management of surrounding country so that wildfires will be very limited in extent. Frequent fire at the edge of this RE keeps fuel loads low. Protection from fire is necessary. ISSUES: Casuarina cristata is fire sensitive, although germination can be good in bare areas. Brigalow is soft-seeded, so germination is not promoted by fire. Buffel grass invasion will increase risk from fire. High intensity fires will cause damage to overstorey. Grazing may be an option for reducing fuel loads where exotic grass such as buffel have invaded. |
| Comments | 11.9.5: Extensively cleared for cropping and pasture. 11.9.5a: Common in the Arcadia Valley and Taroom area. |
1 Estimated extent is from version 13.1 pre-clearing and 2021 remnant regional ecosystem mapping. Figures are rounded for simplicity. For more precise estimates, including breakdowns by tenure and other themes see remnant vegetation in Queensland.
