Regional ecosystem details for 4.9.7
| Regional ecosystem | 4.9.7 |
|---|---|
| Vegetation Management Act class | Least concern |
| Wetlands | Not a Wetland |
| Biodiversity status | No concern at present |
| Subregion | 4, 5, (11.26), (5.5), (10.4), (6.9), (10.1), (10.2), (6.6), (5.4) |
| Estimated extent1 | Pre-clearing 1254000 ha; Remnant 2021 1174000 ha |
| Short description | Astrebla lappacea tussock grassland, wooded with Acacia tephrina +/- A. cambagei and Atalaya hemiglauca on Cretaceous sediments |
| Structure code | Tussock Grassland |
| Description | Astrebla lappacea tussock grassland, occasionally with A. squarrosa and A. elymoides. Iseilema vaginiflorum and Panicum decompositum may occur. Emergent Acacia tephrina and/or A. cambagei commonly occur. Occasional Atalaya hemiglauca, Ventilago viminalis, Alectryon oleifolius and Flindersia maculosa may also be present. Scattered low shrubs are present, but rarely form a distinct layer. Occurs on flat to gently undulating plains formed from Cretaceous sediments. 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). Vegetation communities in this regional ecosystem include: 4.9.7a: [RE not in use]²: This vegetation community is now mapped as 4.9.11x2. Acacia tephrina low woodland. A. cambagei occasionally occurs as a co-dominant. Scattered low shrubs are present, but a low shrubby layer rarely occurs. Astrebla spp. usually dominate the ground layer, but other short grasses and forbs occur. RE is defunct. Not a Wetland. (BVG1M: 27a). 4.9.7x1: [RE not in use]²: This regional ecosystem is now mapped as 4.9.11x2. Acacia tephrina and/or Acacia cambagei low open woodland to woodland, occasionally with Atalaya hemiglauca. The ground layer is tussock grasses, predominantly Astrebla spp. Occurs on undulating plains derived from Cretaceous mudstones. Cracking clay soils. Not a Wetland. (BVG1M: 27a). |
| Supplementary description | Mills (1980), T1, T2, T3 (LU 51); Neldner (1991), 12 (26), 44a, 44b (91); Turner (1978), T2; Turner et al. (1993), T1, T2 (49, 50) |
| Protected areas | Idalia NP |
| Special values | 4.9.7: Potential habitat for NCA listed species: Acacia crombiei, Calotis suffruticosa, Eremophila stenophylla. |
| 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 | 4.9.7: Where clumps of Acacia cambagei or Acacia tephrina are greater than 5ha these areas are mapped as Acacia cambagei (4.9.11) or Acacia tephrina (4.9.8a) low open woodland. Some areas have been cleared. Little regeneration of Acacia tephrina is occurring. Some areas associated with increased woody cover between 1951 and 1994 (Fensham and Fairfax, 2004). Seedling regeneration of Acacia cambagei has expanded onto adjacent grasslands in some areas. Floristic composition of ground layer is variable and affected by seasonal conditions and grazing history. 4.9.7a: Little regeneration of Acacia tephrina is occurring. Seedling regeneration of Acacia cambagei has expanded onto adjacent grasslands in some areas. Some areas have been cleared. |
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.
