2008-2011 Woody Weed Control Farm Beach to Gallipoli Beach
LECCA has undertaken revegetation works along the 5km of coastline between Farm Beach and Gallipoli over a number of years prior to 2008. The success of this revegetation is clearly evident with the planting now naturally regenerating. However, the natural regeneration is threatened by the spread of woody weeds, mainly olives. The nearby coastal samphire wetlands at Salt Creek was also heavily infested with feral olives.
In 2009 we had the Californian Conservation Corp assist with works around Coffin Bay. This was through an exchange program with the Australian Conservation Volunteers. It was interesting to hear about the battles that the CCC has removing Australian eucalypts which have become weeds in Californian forests.
2011 Protecting coastal vegetation from the spread of “environmental weeds”
The group held Weed Swap Days for several years in Coffin Bay, Louth Bay and Tulka on Lower Eyre Peninsula to raise awareness of the potential for garden plants to become weeds in the coastal environment.
2011 Mapping of the environmental weed Polygala myrtifolia (Polygala, Bellarine pea, myrtle leaf milkwort)
Polygala is an environmental weed and a serious pest plant of the coastline of Lower Eyre Peninsula. Our group received funding from the SA Natural Resources Management Program to survey and map the infestation of the environmental weed Polygala myrtifolia across Lower Eyre Peninsula. The data collected informed a strategy for containment and prioritisation for local on-ground works.
Mapping was undertaken by on-ground survey during flowering, Sept-Oct, using GPS and recording density. We employed contractors to assist with the survey and the data was collated into a GIS database and maps produced showing extent and density across the Lower Eyre Peninsula coastal zone.
The weed was declared as a noxious weed in South Australia in 2016.
LECCA received funding to engage a contractor to undertake the feral olive (Olea europaea) control due to the extent of the infestation and the “drill and fill” method to control feral olives was being trialled. Apple of Sodom (Solanum linnaeanum) was also removed over 270 ha from Farm Beach to Gallipoli.
The advantages of the drill and fill method are minimum disturbance to the environment, preservation of habitat (dead standing trees offer perching/feeding sites for birds, safer than lopping (absence of chainsaws) and simple and highly portable tool kit. Most important is the dilute solutions of herbicide used. Trials have shown that the dilute herbicide solutions are taken up more easily by the plants. With less herbicide used the technique is cheaper and better for the environment with a very high, long-term effective strike rate, so little or no follow-up required. Revegetation was then undertaken with local native plants to fill the space made by the removal of the olives.