Stability of native pastures during drought

Silcock, R.G. Dr; Ph: (07) 4631 4200; Fax: (07) 4634 7421; silcocr@dpi.qld.gov.au

Brady, S., Ph (07) 4622 3930; Fax: (07) 4622 4824; bradys@dpi.qld.gov.au

Research organisation: Queensland Department of Primary Industries, Queensland Beef Industry Institute, PO Box 102, Toowoomba, Qld 4350

Queensland Beef Industry Institute, Roma Research Stn, PO Box 308, Roma, Qld 4455

Objectives:

1. To document the native and naturalised pasture species which were most stable during a protracted drought on a range of soil types;

2. To document which native species most readily recolonise abandoned cultivation in southern inland Queensland and the western Darling Downs;

3. To compare the effects of drought in the Maranoa with other regions with similar pasture species;

4. To inform land managers about the species which are most resilient and most susceptible to drought in those regions and propose sustainable management systems to favour desirable species.

Methodology: The project will describe the changes that have occurred in native pastures at 5 sites around the western Darling Downs and Maranoa since 1987. Adjacent cropping land that has been retired to pasture will be compared with the uncleared native pasture to determine what species readily recolonise old cropland. The period covered includes the severe drought of the early 1990s and the recovery which has occurred since. Five data sets currently exist for each site. This data will complement other work done at Charleville in the 1970s and 1980s (including the 1980/82 drought) and at Injune and Rubyvale since 1992. It also links to work done at the same time which determined the most useful sown forage plants for the same soil types under the same climatic conditions. A native pasture Agronomist would be appointed to Roma to co-ordinate the work and link to the Charleville and Rubyvale sites through Dr Silcock's data files. The information from the 1990s drought in the Maranoa will be compared with that for the same species at other sites during different droughts where data is available eg. QGRAZE sites. Results will be published and disseminated to farmers, graziers and Government operatives for their use in determining best options for integrated property management in the region.

Progress: A research ecologist was appointed early in 1998 and has begun processing existing data sets from the Maranoa district, dating back to 1988. The charted pasture dynamics are being entered into a database and will be supplemented by more field recordings during the 1998-99 summer. Other pasture dynamics collected using similar techniques at Injune and Rubyvale are also being processed to allow comparisons from different seasonal conditions.

Period: starting date 1998-01; completion date 2000-03

Status: ongoing

Keywords: cropping systems; land management; native pastures; sown pastures

Publications: None as yet