Amongst the 220+ species of indigenous plants, not counting orchids, found so far at Rubicon, seven species are listed as threatened. In our Landowner's Management Plan, we have prioritised these species according to the significance of Rubicon to their survival in Tasmania. We present below these species in priority order.
Cassinia rugata is a very rare shrub that was thought to be endemic to Victoria until Phil identified it in our wetter places. His identification was substantiated by Dr Tony Orchard, who had recently completed a revision of the Cassinia genus. We have about 300 plants of Cassinia rugata and each year we monitor their numbers. In Tasmania, this species is now known with certainty only from Rubicon and the nearby Carter property. Plants are most easily detected when flowering in February.
There are few known locations in Tasmania for Isolepis stellata. Plants are easily identified by their black seeds, but there are several species of Isolepis that look superficially similar.
There are about 20 known locations for swamp wallaby grass, Amphibromus neesii, all in northern Tasmania. At Rubicon, the known population is fairly small and in an ephemeral wetland.
Gratiola pubescens, hairy brooklime, has become better known from many new locations around Tasmania in recent years. Plants are sometimes locally abundant, particularly in situations subject to flooding.
The leafless milkwort, Comesperma defoliatum, is known from about 8 known locations in northern Tasmania, including Rubicon. It is much more widely known in southern Tasmania. Its small size, need for disturbance and flowers that can close in cloudy weather, makes this species difficult to detect.
Leafy fireweed, Senecio squarrosus, is quite widely reported in the eastern half of the State as a woodland species. At Rubicon it grows in wetlands and is only prominent soon after a burn. It is fairly easy to identify, compared with other fireweeds, with its relatively large individual flower heads.
Juncus amabilis, the gentle rush, is one of the large tussock-forming rushes, distinguished by greyish stems and flowers in dense clusters. A few tussocks are known at Rubicon, sometimes growing in and amongst tussocks of other species.