Weeds and Bushcare News

Blue Mountains Hanging Swamps Walk

October 8, 2005

by Chris Dewhurst – Bushcare Team Leader – Blue Mountains City Council

A mild and sunny afternoon greeted the 16 participants who made their way to Katoomba for the tour of Minnehaha Reserve. Chris Dewhurst (BMCC Bushcare Officer) introduced the afternoon by providing a little background to Council’s Bushcare program and the community work that has been done in the area.

The Minnehaha Falls Bushcare Group was one of the first to start in the mountains, beginning in 1989. They immediately began addressing the issue of weeds, most notably Scotch Broom (Cytisus scoparis) and Gorse (Ulex europaeus).

As in so many Blue Mountains reserves, the impact of sedimentation has been massive on this area. The Minnehaha Falls, once known as a "Bottomless Pool", has been filled by sediment and is now ankle deep.

The Bushcare Group and professional contractors have succeeded in achieving complete primary knockdown of the weeds in Yosemite Creek, yet they were faced with a "Bush Regeneration Emergency" when the December fires of 2002 burnt the catchment – stimulating massive seedling germination and threatening over 10 years of work. Council and the community threw everything they had at the problem, and a series of "Broom Blitz” events were successful in abating the crisis.

Chris then introduced Clive Heywood Barker (Environmental Consultant and top class naturalist) to the group. Clive talked about the listing of "Temperate highland Peat Swamps on Sandstone" (known as "Hanging Swamps" in the Blue Mountains) under the Environmental Protection and Biodiversity Conservation Act 1999.

The geology is a major determinant in the formation of a Hanging Swamp. The porous sandstone is layered with impermeable ironstone and shale belts. The water can flow easily through the sandstone, but when it hits hard ironstone it is forced to the surface, causing permanent damp conditions and sometimes springs. The swamp vegetation and peat formations then colonise this environment.


Clive Barker (far left) explains the dynamics of the Hanging Swamp in the background. A sediment trap designed for easy vehicle maintenance is shown in the foreground.
Photo: Chris Dewhurst

The biodiversity of Hanging Swamps include the rare Blue Mountains Water Skink (Leura Skink, Eulamprus leuraensis) and the Giant Dragonfly (Petalura gigantea) – both listed under the Threatened Species Conservation Act 1995. Impacts include threats from urban run-off, especially sedimentation and invasion by exotic species including the feral Rhododendron (Rhododendron ponticum)


Almaleea incurvata was found in flower along the walk.
Photo: Chris Dewhurst

The group walked around a number of Hanging Swamps on the journey to Minnehaha Falls. We encountered many flowering plants including the rare Almaleea incurvata (pictured), Sprengelia incarnata, Epacris pulchella and Grevillea acanthifolia amongst many others.

We enjoyed hosting an AABR event, and hope many of you can make it to our future activities.

You can be informed of what is happening in the Blue Mountains by joining our email list – send an email to Chris Dewhurst via this website's feedback form asking to be added to the list.