Regional ecosystem details for 2.9.2
| Regional ecosystem | 2.9.2 |
|---|---|
| Vegetation Management Act class | Least concern |
| Wetlands | Not a Wetland |
| Biodiversity status | No concern at present |
| Subregion | 8, 6, 3, (2), (1), (4), (1.3) |
| Estimated extent1 | Pre-clearing 147000 ha; Remnant 2021 146000 ha |
| Short description | Aristida spp., Eulalia aurea, Dichanthium spp. and Heteropogon contortus in mixed tussock grasslands on undulating plains on fine-grained Cretaceous sediments. |
| Structure code | Tussock Grassland |
| Description | Mixed tussock grassland to closed tussock grassland, including combinations of the species Aristida spp., Eulalia aurea, Dichanthium spp., Heteropogon contortus, Chrysopogon fallax and Ophiuros exaltatus. Other species include Themeda arguens, Iseilema spp. and Astrebla spp. Emergents include Terminalia spp., Lysiphyllum cunninghamii, Corymbia confertiflora and Eucalyptus spp. Occurs on level to undulating plains on fine-grained Cretaceous sediments. Yellow to brown calcareous cracking clays. Not a Wetland. (BVG1M: 30b). Vegetation communities in this regional ecosystem include: 2.9.2a: Mixed tussock grassland to closed tussock grassland, including a combination of the species Aristida latifolia, Eulalia aurea, Dichanthium fecundum, Chrysopogon fallax and Astrebla elymoides. Other species include Eriachne glauca var. glauca, Brachyachne convergens, Astrebla squarrosa and Iseilema vaginiflorum. Occurs on gently undulating plains on fine-grained Cretaceous sediments in the west of the bioregion. Yellow to brown cracking clays. Not a Wetland. (BVG1M: 30b). 2.9.2b: Mixed tussock grassland, including combinations of the species Aristida spp., Dichanthium spp., Heteropogon contortus, Themeda arguens, Iseilema spp., Bothriochloa sp. and Astrebla squarrosa. Emergent Terminalia spp., Lysiphyllum cunninghamii, Corymbia confertiflora, Eucalyptus chlorophylla and E. cullenii may occur. Occurs on undulating Cretaceous mudstone/siltstone plains in the north-east of the bioregion. Orange to brown calcareous cracking clays. Not a Wetland. (BVG1M: 30b). 2.9.2c: Ophiuros exaltatus closed tussock grassland. Other species include Heteropogon contortus, Dichanthium sericeum subsp. polystachyum and Schizachyrium fragile. Occurs on low-lying Cretaceous mudstone/siltstone plains in the north-east of the bioregion. Brown calcareous cracking clays. Not a Wetland. (BVG1M: 30b). 2.9.2x3: [RE not in use]²: This regional ecosystem is now mapped as 2.5.42. Triodia pungens hummock grassland, occasionally with Aristida spp., Schizachyrium fragile and Eriachne spp. Emergent Corymbia grandifolia subsp. grandifolia, Terminalia canescens, Acacia hammondii and Eucalyptus pruinosa subsp. pruinosa may occur. Occurs on waning slopes of clayey sandstone and siltstone (Floraville Formation), exposed around margins of Tertiary lateritic surfaces. Orange loam soils. Not a Wetland. (BVG1M: 19c). |
| Supplementary description | Perry et al. (1964), Punchbowl, Cowan, Donaldson, Donors, Manrika |
| Fire management guidelines | SEASON: March to April, with occasional storm burns if woody weeds are a problem. x3: Burn in the wet season or very soon after. INTENSITY: Low, occasionally moderate and high intensities. x3: Low to moderate, although spinifex will naturally burn with high intensity in some areas. INTERVAL: 3-6 years in latitudes south of Karumba, 1-3 years to the north. x3: 2-7 years. Fire-killed acacias produce seed at 5 years, so some longer unburnt patches need to be retained. INTERVAL_MIN: 1. INTERVAL_MAX: 7. STRATEGY: Do not actively target burning of sedgelands. Commence burning early in dry season to break up continuity of fuel across the landscape. Mosaic burning across the landscape at varying frequency will create patches at varying stages of post-fire response. Burn with good soil moisture to promote regeneration. x3: Apply fire at sufficient intervals such that hummocks do not form a continuous fuel layer across the landscape. Use broad scale mosaic burning. Burn when the soil is moist as it promotes post-fire recovery of spinifex. ISSUES: Retaining grasslands by preventing woody thickening may be an issue in some situations. A long absence of fire or low intensity fire too early in the season may lead to overabundant seedlings and saplings. Invasive and high biomass grasses (e.g., buffel, Para and grader grasses) may increase fire severity to the detriment of these ecosystems. x3: Spinifex is highly flammable. Green spinifex will also burn readily. |
| Comments | 2.9.2b: Previously mapped as 2.9.3x1a. Subject to degradation from high total grazing pressure. Commonly invaded by *Themeda quadrivalvis (grader grass). 10-30% of its pre-clearing extent remains unaffected by severe degradation and/or biodiversity loss. Severe infestation of *Themeda quadrivalvis. 2.9.2c: A rare vegetation community. Previously mapped as 2.9.3x1b. Commonly invaded by *Themeda quadrivalvis (grader grass). 10-30% of its pre-clearing extent remains unaffected by severe degradation and/or biodiversity loss. includes significant infestations of *Themeda quadrivalvis. 2.9.2x3: A rare ecosystem with limited extent. |
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.
2 Superseded: Revision of the regional ecosystem classification removed this regional ecosystem code from use. It is included in the regional ecosystem description database because the RE code may appear in older versions of RE mapping and the Vegetation Management regulation.
