Fishbone mat being pushed back

Our Tuesday afternoon bushcare group, Mt Gravatt Bush Blokes, are really making their mark with a large section of Fox Gully now clear of Fishbone Fern Nephrolepis cordifolia.

Fishbone Fern commonly spreads into our bushland through garden waste dumping. Simply dumping garden prunings is not “mulching” as a contractor recently tried to tell me. Garden green waste dumping is one of the three key threats to Mt Gravatt Reserve. The other two threats are downhill mountain biking/unofficial tracks and feral animals/uncontrolled domestic pets.

Michael with Catch of The Day

Fishbone is a good case study of how of garden waste dumping threatens our precious remaining parcels of suburban bushland. Like most ferns, Fishbone can spread by wind-blown spores, however each plant appears to produce only a few fertile fronds. Therefore, the main way this invasive weed is spreading at our site is via runners or stolon, similar to the runners on strawberry plants.  The word “stolon” comes from the Latin word “stolō” meaning a shoot, branch, or twig springing from the root.

Most of the site is thickly coated in Fishbone which is removed easily but cannot be composted on-site. The stolons and hairy tubers do not decompose easily and will simply re-shoot: approximately one hundred and fifty garbage bags of Fishbone removed to-date.

Forest Pittosporum

At the edges of the infected area the fern stolons are spreading among the native grasses. It is common to pull out a metre long runners with new tubers attached. Left in-place these runners develop in a mat of weed smothering all other plants. It is slow work then you find positive signs of natural regeneration like this flowering Forest Pittosporum Pittosporum revolutum.

My current observations suggest that once we have cleared the Fishbone re-infection by spore transmission is unlikely. Ongoing education is dramatically reducing green waste dumping so with the Fishbone removed natural regeneration with indigenous ferns and grasses will reduce edge-effect and provide long-term consolidation of this unique habitat.