Regional ecosystem details for 11.4.4
| Regional ecosystem | 11.4.4 |
|---|---|
| Vegetation Management Act class | Least concern |
| Wetlands | Not a Wetland |
| Biodiversity status | Of concern |
| Subregion | 7, 2, 4.4, 11, (10), (26), (15), (6), (21), (6.4), (13), (5), (20), (23) |
| Estimated extent1 | Pre-clearing 74000 ha; Remnant 2021 28000 ha |
| Short description | Dichanthium spp., Astrebla spp. grassland on Cainozoic clay plains |
| Structure code | Tussock Grassland |
| Description | Dichanthium spp. +/- Astrebla spp. tussock grassland (mainly A. lappacea and A. pectinata). Other grasses frequently present include Thellungia advena, Panicum spp. and Aristida spp. Forbs and annual grasses may become common with seasonal rains. Occasional shrubs and trees may be present in places. Occurs on flat to gently undulating clay plains formed from Cainozoic or weathered basalt unconsolidated sediments. Soils are generally moderate to deep to very deep dark grey self-mulching cracking clays with linear gilgai. Gravel or stone may be present in some areas. Not a Wetland. (BVG1M: 30b). |
| Supplementary description | Gunn et al. (1967), Avon (1), Kinsale (5), Moray (3), Wondabah (1); Speck et al. (1978), Highworth (4); Gunn and Nix (1977), LU 43, 102, 109; Fensham (1999), Mitchell grass on alluvium (in part); Burgess (2003) (VA28), Carfax |
| Special values | 11.4.4: Habitat for threatened plant species including Dichanthium queenslandicum. Often occurs adjacent to lower lying areas dominated by regional ecosystems 11.4.11 and 11.3.3. |
| 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 | 11.4.4: Subject to invasion by Parthenium hysterophorus particularly in association with high total grazing pressure or periods of drought. The presence of dominant grass species varies with grazing and seasonal conditions. |
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.
