Rainforest Ferns 17

Some ferns in tropical rainforests, like the Daintree in Queensland, can be huge – they are known as Tree Ferns. There are two species in that region: Cooper’s Tree Fern (Cyathea cooperi) as shown above; and Rebecca’s Tree Fern (Cyathea rebeccae) as shown in the thumbnail image left (click it to enlarge the picture) and in the close-ups below. In both species, the stem or stalk can grow many metres high and is covered with a repeating pattern of scale-like scars that indicate where individual fronds were once attached.

At the top of the stalk is a crown of fronds with regular series of pinnules, the whole structure resembling a lovely parasol. In the Cooper’s Tree Fern, at least a dozen of these light green fronds are symmetrically arranged around the stem, which is slightly thicker than in Rebecca’s Tree Fern. The crown of fronds at the top of Rebecca’s Tree Fern has a more hap-hazard arrangement with slightly darker green fronds protruding at odd angles from a more slender stalk; and characteristically with dead brown fronds tending to remain in position for quite a while and hanging down from the centre of the crown of fronds.

Looking up into the Tree Fern crowns, the natural regular designs of the green fronds and their constituent pinnules make intricate lacy patterns as they are silhouetted against the clear blue sky.