Black Tree Fern, Cyathea medullaris
The Black Tree Fern (Cyathea medullaris), is a species of evergreen tree fern endemic to New Zealand. New Zealand forest is evergreen due to the mild climate. Groups of lightly interspersed black tree ferns are common sights and very prominent on the rather steep but overgrown slopes of the North Island volcanic landscape.
This fern is found to grow to heights of 65 feet, making it the largest tree fern. It may have been named because the stalk of each mature frond is black with a rather bluish tinge if seen from the underside. Also, the fiddleheads are covered in a dark brown furry layer of plant material.
To the casual observer, black tree ferns might look more akin to palm trees than to woody trees, but they are not closely related to either. Its fronds have rather little overlap and do not shade each other very much.
It has no secondary growth and no wood. Nevertheless, tree fern stalks, including black tree fern, have been used as building material and they are still used for makeshift track-work.