Getting creative with integrated weed management

Article by Rhea Phelan, vector and pest plant officer, Sunshine Coast Council

Almost 3 years ago, Andrew and Claire became stewards to 3.5 acres of land in the headwaters of the Obi Obi. They called it 'Maleny Eco Village’ which was bought by ‘Eco Villages Australia,’ a non-profit organisation committed to caring for people, animals and environment. They knew that weed management was going to be one of their tasks and so they quickly joined Sunshine Coast Council’s land for wildlife program, joined their local bush care group and connected with the roving restorers and hinterland bush links. In fact, 15 minutes after they moved in, they had Spencer Shaw of Brush Turkey Enterprises identify trees and weeds. The biodiversity and mature trees were, in fact, the main draw card of the property. But they knew they had a steep learning curve in front of them.

There were several weeds that are declared as restricted invasive plants under the Biosecurity Act 2014 and listed as priority weeds for management under the Sunshine Coast Council local government area biosecurity plan 2017 growing on the property. Since moving to the property, Andrew and Claire along with others have worked hard to recover the biodiversity and restore ecosystem function to the property which was being heavily impacted by invasive plants. On the property they have had invasive aquatic plants like salvinia, invasive vines such as madeira vine (Anredera cordifolia), climbing asparagus fern (Asparagus africanus), morning glory (Ipomoea indica), groundcovers like Singapore daisy (Sphagneticola trilobata) and a selection of weedy trees and shrubs like camphor laurel (Cinnamomum camphora), green cestrum (Cestrum parqui), Celtis sinensis and Ochna serrulata.

Andrew and Claire have decided not to use chemicals on the property, so the majority of removal has been done by hand, using an integrated weed management approach. They focus on the vines in winter when they are at their weakest. Salvinia was removed from the dam by draining it and using an excavator and the weeds haven’t returned. They have also completely eradicated basket asparagus fern. Andrew recently hired a tree popper from Sunshine Coast Council to help manage weedy tree saplings. All the hard work is starting to pay off as native plants are beginning to make a comeback along with the insects, birds and other animals that rely on them for survival. They are setting aside some of the area for habitat while establishing food gardens in other areas. They lean heavily on regenerative agriculture so the mulch is provided by the vegetation grown on the property.

Steward, Andrew said “Weeds can be useful in integrated weed management, we encourage people to get creative and start to form a different relationship with them. We deal with 99.9% of our organics on the property we recycle them through weed teas, ‘cut and drop’, composting and biochar. ‘Weed tea’ is made by putting all the weeds into a container with water so they decompose and become fertiliser which can then be put on other plants”.

“To prevent mosquitos breeding in the water it is a good idea to put some mosquito netting over the container. Dead trees provide habitat and as they break down they become the soil to feed the plants you want. With food supply lines under pressure, it’s time to start looking at what the land wants to provide us and what grows well in your area”.

“My taste buds have changed and I look forward to the annual bunya nut feasts, chokos, pomelo, paw paw, tamarilo and pumpkins each year. We use the weeds like wild tobacco to shade out a lot of the herbaceous weeds that need sun until the black wattle (Acacia mearnsii) and bleeding heart (Homalanthus populifolius) come up. It’s like a bad haircut, there is that awkward in-between time that nothing but time can fix. Being caretakers of the property is a long-term proposition and slow long-term solutions are often the best.”

Andrew and Claire have integrated a variety of tools into their land management practices to manage the weeds on their property and are having some great success by getting rid of them while using them to enhance the property. When using restricted invasive plants, for example in composting while working towards eradicating them, it is critical to ensure you are not spreading them further. These plants spread very easily, growing from stem fragments, tubers and seeds which can sometimes stay viable for a long time and even through the composting process. That said, reducing inputs to the property by recycling green waste onsite can also help prevent new weed incursions!

If you would like to get started managing invasive shrubs and trees like Andrew and Claire and hire a tree popper free of charge, please contact Sunshine Coast Council on [email protected]. Tree poppers are available in 3 sizes, small (removes plants with a stem diameter of 5-20mm), medium (remove plants with a stem diameter up to 40mm) and large (remove plants with a stem diameter up to 60mm).