Research results to be presented at the Australian Rangeland Society biennial conference in Bourke this September 26 to 30, have shown that short-term cropping can be used to restore native perennial grasses to pastoral land in western NSW.
Industry & Investment (I&I) NSW rangelands researcher, Yohannes Alemseged, said that temporary cropping had helped eliminate invasive native scrub (INS), including turpentine, budda and hopbush, on the Cobar pediplain.
“A total of 30 paddocks which had been cropped in the last 20 years were surveyed and we found that once short-term cropping was used to remove INS, beneficial perennial grasses could be successfully restored,” Dr Alemseged said.
“Post-cropping grazing management was a key factor and it’s critical that the correct grazing management is used to reap the benefits gained by the cropping phase.
“We found that ground cover, native perennial grasses and standing dry matter were highest under light, rotational grazing.”
The study showed that sufficient viable seed remained in the soil and native perennial grasses were able to respond in favourable seasonal conditions.
Dr Alemseged said a combination of nitrogen applications and grazing management may have also promoted seed production from perennial grasses which established following the crop to provide a larger seed pool in subsequent seasons.
“Pastoralists could also look at sowing a crop in regenerated paddocks every few years using direct drilling techniques which result in minimal disturbance of soil and ground cover,” he said.
“Intermittent cropping could prevent the re-establishment of INS, enhance water infiltration and improve soil fertility with soil organic carbon build-up and direct additions of fertiliser.
“Ground cover is a key indicator of rangeland sustainability and studies have shown its importance in managing water infiltration, run-off and soil erosion.”
The restoration of native perennial grasses promises to result in more productive and resilient landscapes, according to
Dr Alemseged.
Pastoralists can register for the conference by calling (02) 6884 4654 or online http://www.arsbourke2010.com.au/
