Regional ecosystem details for 4.9.9
| Regional ecosystem | 4.9.9 |
|---|---|
| Vegetation Management Act class | Least concern |
| Wetlands | Not a Wetland |
| Biodiversity status | No concern at present |
| Short description | Astrebla spp. grassland wooded with Vachellia sutherlandii or Acacia victoriae on Cretaceous sediments |
| Structure code | Open Tussock Grassland |
| Description | Astrebla lappacea (5-30% cover) usually predominates forming a tussock grassland. In places, A. pectinata may predominate. A. squarrosa and A. elymoides are codominant occasionally. Iseilema vaginiflorum and Panicum decompositum are frequently conspicuous. Other tussock grasses and forbs are present when seasonal conditions are favourable. Low, scattered Vachellia sutherlandii or Acacia victoriae trees are always present. Scattered low shrubs are present, but rarely form a distinct layer. Occurs widely on flat to gently undulating plains frequently adjacent to alluvia or fringing undulating downs. Soils moderately deep to deep, brown cracking clays derived from weathered sediments of Cretaceous Winton Formation. Soils usually self-mulching beneath a weakly developed crust. Not a Wetland. (BVG1M: 30b). |
| Supplementary description | Neldner (1991), 44d, 44e (99); Turner et al. (1993e), F3 |
| Fire management guidelines | INTERVAL: Fire return interval not relevant. INTERVAL_MIN: 100. INTERVAL_MAX: 100. STRATEGY: Do not burn deliberately. The grasses and forbs of Astrebla spp. dominated communities do not require fire for regeneration. Protection relies on management of fire in the surrounding country to prevent running fires entering Astrebla spp. communities, particularly at times of low soil moisture. ISSUES: Fire can sometimes be used as a tool to control woody thickening and woody weeds in grasslands. Moderate intensity fire is required for a successful kill of the woody species but good moisture levels are required to ensure recovery of the ground layer. Large scale germination of woody species is most likely to occur in high rainfall years. The best management opportunity is usually after storms at the end of the subsequent dry season, although exclusion of grazing pressure may still be required to ensure sufficient fuel loads. |
| Comments | 4.9.9: Floristic composition of ground layer variable, affected by seasonal conditions and grazing history (Neldner, 1991). |
1 Estimated extent is from version 13 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.
