Filmy Ferns are a feature of the wet gullies and rainforests in Tarra Bulga, they are usually found as epiphytes growing on the trunks of trees and other ferns, especially Soft tree-fern (Dicksonia antarctica) as well as rocks and steep embankments . There are five different species known to occur in the park and although they are small and delicate, with a bit of practice it is easy enough to learn to tell the difference between each species. Four of them belong to the same genus (Hymenophyllum). Along with the Filmy ferns there are many species of Mosses and Liverworts that flourish in similar moist sheltered locations.
Click on the Galleries for Closer Views and Photo Descriptions
Austral Filmy-fern Hymenophyllum australe
This fern is dark green and not particularly shiny. It is common and easy to identify by the wing which is several millimetres wide and extends all the way along the central wiry stem from the tip of the frond to the base (stipe) where it is attached. It has lots of spore producing sori at the tips of the fronds. The sori have 2 lips and they often present in pairs.
Colony on Tree Fern
Winged stipe where it attaches to the rhizome.
Fertile frond with pairs of indusium covering sori.
Close up of fertile frond with pairs of fertile sori.
Shiny Filmy-fern Hymenophyllum flabellatum
This is another very common fern found in the rainforest gullies. As indicated by its common name it is very shiny and it is a lighter green than the Austral Filmy-fern. The stem (stipe) does not have a wing and has a tuft of hairs at the base. The pinnae (ends of the fronds) often form a fan shape. The sori (spore producing bits) at the tips of the frond segments are wider than the rest of the leaf.
Fan shaped frond segments
Shiny Frond with indusium at tip of segments.
The stems (rachis) are not winged along the whole length.
Frond – Not the hairy base of the stem.
Common Filmy-fern – Hymenophyllum cupressiforme
Common Filmy-fern is easily found and identified by serrated margins of its outer fronds. It has large spore producing sori which are located close to the main stem (rachis) of the frond. Alpine Filmy-fern (Hymenophyllum pelatum) also has serrated margins of it frond segments (pinnae) but it has never been found in the Tarra Bulga.
Frond, note the serrated margins.
Indusium, close to rachis.
Large black sori located close to the central stem.
Narrow Filmy-fern – Hymenophyllum rarum
As its Latin name suggests this fern is the hardest to find of all the local species. It will often grow among Common – Filmy fern (e.g. Along the East-West track in the Tarra Valley picnic area) and superficially looks similar. As its common name suggests it is narrow, It has a narrow wing along its main stem which may cause confusion with Austral Filmy-fern, but a clear distinguishing feature is the the V shape made by the veins at the base of the indusium (tissue protecting the spores) at the tips of fertile frond segments. Click on the Gallery below for a better view.
Close up (magnified) of tips of fertile fronds. Note V shaped veins.
With V shaped veins at the tip (below the indusium)
Where stipe attaches to the rhizome.
Fronds segments divide on one half only.
With V shaped veins at the tip (below the indusium)
Frond has a narrow wing.
Veined Bristle-fern – Polyphlebium venosum
Is the only species of the 5 ferns not in the genus Hymenophyllum. It is very common in the same habitats as the other occur. It is distinguished by its very delicate pale green shiny fronds (only one cell thick). Tiny branched veins are clearly visible on the narrow fronds. The fertile fronds have a trumpet shaped spore cover (indusium).
Fertile fronds with trumpet shaped indusium protecting the sori.
With colony of delicate fronds.
Network of veins are easily visible.
This is the time of year when most of the daisy species in Tarra Bulga are in flower. A number of species look quite similar and a bit of knowledge is often needed to tell one from another.They are all medium shrubs with narrow linear leaves and similar looking cauliflower like flower-heads.
One group are the Cassinias’ there are three separate species and all of them occur in the more open and exposed sections of the park rather in the shaded and protected gullies
Cassinia aculeata – (Common Cassina or Dogwood) has the the shortest and narrowest leaves of the three. If you look underneath the leaves you can see that they are curled over at the edges. Another distinguishing feature is that the new flowers are sometimes pink rather that white.
Flower head, in this case showing the Pink Form
Showing the underside of the narrow leaves that are hair below with recurved margins.
Showing white flowerheads this time.
Cassinia longifolia – (Shiny Cassinia) has broader and longer leaves and the new leaves are noticeably shiny and sticky to touch. The underside of the leaves are covered in short dense hairs and the vein down the middle is very prominent.
Showing the Shiny upper-side of the leaf which can be sticky and has a prominent mid-vein.
Showing the underside of the leaf with dense hairs and the mid vein.
Typical shiny leaves
Cassinia trinerva – (Three-veined Cassinia)Has leaves that are also broader and longer than Common Cassina, they are quite soft and not shiny or sticky. They have a big vein running down the middle of the leaf and two smaller veins that run a millimetre or two inside the leaf margins.
Underside of leaves showing the 3 veins that give the species its name.
Cassinia trinerva – Three-nerved Cassinia
Flowerhead which again looks very similar the the other 2 species in the park.
Cassinia trinerva – Three-veined Cassinia
Ozothamnus ferrugineus (Tree Everlasting) is a fourth species that can be confused with the Cassinia’s as it is a similar size and has similar leaves. It’s leaves are around the same size as Cassinia longifolia (Shiny Cassinia) but its leaf margins are usually a little wavy. With close examination the flowers are clearly different to Cassinias, they have little bracts around the individual florets.
Leaves look fairly similar to Shiny Cassinia but the edges tend to be a little undulating.
Underside of the leaves has a creamy white – felty texture.
Side view of flowers, which can be identified by the separate mini florets.
Another view of the flowers, Note the difference to Cassinias.
They also have a woody trunk, Which is probably the source of their common name.