The king fern Angiopteris evecta looks superficially more like a palm crown growing directly out of the ground but this is actually a relic fern from the late Paleozoic era. The fronds might be the longest in the world for a fern, reaching as much as 5m A good place to see king ferns is along the road to Cape Tribulation, and the Nandroya Falls track in the Palmerston section of Wooroonooran National Park south of Cairns.
Promotional photographs of the Wet Tropics often feature the tree fern, a species which imparts a tropical yet ancient feel to the area. Tree ferns have been here since the dinosaurs but the modern species are only small versions of their ancestors.
The scaly tree fern Cyathea cooperi is an attractive and characteristic tree fern with its node scars scales covering its narrow trunk and horizontal crown of feathery fronds. The crown is said to reach up to 12m 40 feet wide and sits atop a thin trunk reaching up to 12m 40 feet tall. This species isn't restricted to the Wet Tropics and can be found in forests further down the east coast of Australia.
A primitive looking fern indeed is the tassel fern and with good reason—its fossils have been identified to much larger specimens from the Carboniferous period. Two very different forms of the tassel fern are almost opposite to each other in habit. Ferns depend on spores that act like seeds to reproduce. If you look underneath the fronds the spores look like tiny pieces of dust.
Spores are so light the wind or even birds can carry them away. When spores land on moist surfaces they have the best chance of making new ferns. Baby ferns whose spores land on other plants need lots of water and some light to grow tall and healthy. Ferns that grow from the ground absorb water and nutrients easily from their strong anchored roots. If you were a fern would you rather grow from the ground or live on top of another one? The fronds are initially erect but then hang down to cover the base.
The base is formed from flat guard leaves that turn brown. The elkhorn fern has multiple centres of frond growth, which distinguishes it from the staghorn fern more likely found in open forests which has only one centre.
The gristle fern is a glossy leaved fern of the forest floor that has beautiful pink new fronds. The fern can be distinguished from most others along the Paluma tracks by the shape of the leaf and the fact that the lobes or leaflets of each frond extend onto the central axis and merge with the adjacent leaflet. Most other ferns of this shape and habit have distinct leaflets arising from the bare central stem. One other fairly common species of fern has this form of merged central leaflets along the stem but it also has small leaf-like lobes extending down the base, whereas in C.
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