Case studies

Gold Coast

Binna Burra, QLD

The challenge

Main Roads Gold Coast contracted us to effectively revegetate an area of extremely unstable steep slopes, with little or no topsoil, just below Binna Burra Lodge in the Gold Coast hinterland. Having been badly affected by the bushfires in late 2019, the area needed urgent regeneration.

The solution

We applied EnviroMatrix ECM – an all-in-one biotic growth amendment – and EnviroBond long-term soil and mulch stabilising polymer to an area of vertical rockface and steep batters with little or no topsoil. Performing the first treatment on 2nd March 2020, we included a seed-blend of millet as the sole cover-crop species, along with native tree and grass species (the goal is to put the forest back to its natural state, and ECM is a native-plant-friendly growth media). No extra soil conditioners or fertiliser were required as everything is included in the ECM product, and rainfall was limited in both March and April (March saw 73 mm total rainfall and April just 18 mm – resulting in slower growth of the establishing plants).

Millet is a summer grass and naturally dies in cooler temperatures, so the second area of treatment (which took place on 24th April) included a rye grass as the cover crop – a winter grass that should establish well if rain occurs. Rain’s essential to this project because of its isolated location – water trucks must travel for an hour to bring water to the site, so the water use efficiency (WUE) of our product is crucial to the project’s success. Keep an eye on our blog for more updates on this highly successful project.

The results

Six weeks after application we returned to find the EnviroMatrix was perfectly bound and exhibiting millet growth, plus other vegetation was establishing. The cover crop had done its job, providing ground-cover and below biomass to stabilise the slopes, whilst some native grasses were establishing. With more rain, we anticipate further establishment of the native species plants sown.

The project also benefited from EnviroMatrix being a single-bag product, rather than requiring several products to do the job, and the application contractor mentioned how easy it is to use due to not having to measure and add the fertiliser and binders separately.

Finally, the cost per hectare when using EnviroMatrix is significantly less than that of our competitors.