Soil extension Project – Consideration of soil types colonised by Buffel grass in the Alinytjara Wilurara Region
Home / Projects / Soil extension project – Consideration of soil types colonised by Buffel grass in the Alinytjara Wilurara Region
Soil extension project – Consideration of soil types colonised by Buffel grass in the Alinytjara Wilurara Region
Lead organisation: Alinytjara Wilurara Landscape Board
Hub members and partners involved: Northern and Yorke Landscape Board
Project Category: Hub Projects
Project summary: 

The SA Drought Hub has partnered with Alinytjara Wilurara Landscape Board (AWLB) to identify the various soil types in buffel grass infestations in the AWLB region and determine the impact soil types may have on buffel grass management.

An invasive weed that impacts rangelands, buffel grass is competes with and eliminates native species, and presents a fire hazard. Buffel grass is often controlled with the chemical herbicide flupropanate.

The efficacy of the residual properties of flupropanate may be affected by such factors as rainfall and soil type. The project team is investigating flupropanate concentration and movement through the soil profile in the varying soil types within the AW region. Soil samples are undergoing laboratory analysis, with the results from this work guiding ongoing management of this invasive weed within the region.

The project also provides training opportunities for staff, ranger groups and contractors on soil testing for land management issues.

Project description: 


Hands-on soil demonstrations and sampling:

  • With AWLB staff guiding site selection, field trip participants were actively involved in digging, collecting soil, identifying soil horizons, classifying soil colour using a Munsell colour chart, hand texturing and classifying soils, testing for carbonate (fizz test with 1% HCl), testing for water repellence, testing for pH, recording GPS location, and photographing sites. Soil samples were sent for nutrient analysis and for flupropanate analysis.

Key achievements and results: 

Field trips
  • August 2023: 13 attendees participated in a 5-day trip with staff from AWLB, Northern and Yorke Landscape Board, Eyre Peninsula Landscape Board, and Far West Coast Aboriginal Corporation.
  • October 2023: 10 attendees participated in a 4-day trip to the Anangu Pitjantjatjara Yankunytjatjara (APY) Lands with APY Land Management staff including Warru Ranger teams, APY Pastoral Program staff and AWLB staff.
  • 30 attendees at workshop demonstrations in Ceduna in September 2023, including representatives of the Far West Coast Aboriginal Corporation, Yalata, and Oak Valley ranger groups; Iluka Resources, Nature Foundation, Eyre Peninsula Landscape Board, National Parks and Wildlife Service South Australia, local contractors, SA Drought Hub and AWLB.

Further information:

Project Images

Participants on the August 2023 field trip to the AW region. Back row (L-R): Richard Lennon, Charles Coleman, Troy Bowman, Lesley Mundy, Brett Backhouse, Paula Modra, Alex Fraser, Geoff Kew, Lucy Porter, Noel Probert; front row (L-R): Matilda Backhouse, Ashlee Benc, Tiah Pepe (photo: Noel Probert, AWLB).


Widespread buffel grass establishment in the APY region (photo: AWLB).


AW Buffel Grass Project Officer Ashlee Benc uses a hand auger to collect soil samples from beneath a buffel grass plant on the Nullarbor Plain. Soil samples are lab-tested for residual flupropanate (photo: Lucy Porter, SA Drought Hub).


AWLB Officer Tiah Pepe uses a pick to collect soil samples from beneath a buffel grass plant as Far West Coast Ranger Richard Lennon (left) and Soil Extension Officer Geoff Kew watch on (photo: Noel Probert, AWLB).


Brett Backhouse (standing), Lucy Porter (collecting) and Ashlee Benc (bagging) sampling soil on the October 2023 APY Lands field trip to gain a better understanding of soil type for the area and how it may influence Buffel grass management (photo: Paula Modra, AWLB).


Testing soil pH with a field test kit. Purple dye indicates a high pH, alkaline soil (photo: Noel Probert, AWLB).


Wetting a soil sample to create a bolus in order to hand texture the soil. This technique is used to estimate the amount of sand, silt and clay, and can provide information on the soil’s characteristics and function by indicating how much water and nutrients it can hold (photo: Noel Probert, AWLB).