Various infiltration and soil erosion mitigation techniques have been applied in some areas on Bon Bon Station Reserve over the past few years, where we've had the tools (and advice) available to start a repair process. We've some attached photos here to show the results so far.
An area of land on a slope leading to sheep yards and crutching shed, cattle yards, stock watering point and an old highway near the Bon Bon Station Reserve homestead has been impacted over the years by livestock concentrating in the area, and by traffic and grading.
The soil on the slope had been compacted, causing water run-off and some erosion down the slope. There was very little vegetation growing and ground cover annuals were unable to establish.
Early in 2016 we hired a large loader from Paul and Louise Simpson for ripping rabbit warrens. Later when Paul returned to assist us, we had an opportunity to use his skills on the machine to do some soil conservation work to repair some of the compaction and slow the run-off down this slope.
The loader had front mounted rippers, which were used to rip the soil in bands along the contour to slow the run-off and increase infiltration. We also ripped across an unused old station track, which was also causing some erosion.
The first photos show the loader ripping the infiltration bands and then water ponding above the ripped areas on the slope after a heavy shower of rain. The next photos show how follow-up rain enabled grasses and other annuals that had germinated in and above the infiltration areas to grow and establish, stabilising the soil on and below the slope.
The final photos (taken in March 2017) show how the vegetation is continuing to establish after some additional summer rain.
Another rehabilitation success we’ve had on Bon Bon over the past few years (using advice from Janet Walton (a local expert in soil and water conservation)) has been the use of tree branches (pruned from the gardens or while maintaining tracks) to fill erosion areas, including along old unused tracks that are channelling water and forming gullies.
The tree branches are placed in the gullies with the branches spreading and pointing up the slope. The branches and leaves then help to slow and spread water as it flows through the area. The leaves eventually drop off the branches also helping to trap seeds, soil and organic matter and over time the area begins to stabilise as the soil is held together and new plants establish.
This method was very successful in repairing an erosion gully that we urgently needed to stabilise to stop part of the airstrip washing away.