Cyathea cooperi

Cyathea cooperi.

Cooper’s or Scaly Tree Fern is in Division Pteridophyta > Order Cyatheales > Family Cyatheaceae.

A common terrestrial fern often found in gardens.
Rhizomes (trunks), growing up to 15 m tall, are hard and dark greyish-brown.
The lower part is often thickened by adventitious roots.
The old leaf bases usually fall off leaving pale, oval scars.

Older trees can have up to 18 broadly ovate fronds each up to 5 m long.
Fronds are dull green above with a paler lower surface. Fiddleheads have whitish scales.

The pale brown frond stalks up to 50 cm long are deeply grooved on the upper surface.
They are covered with tiny brown nodules up to 0.5 mm high.

There are 2 types of scales on the stalk bases:

  • Larger thin, white, papery scales 2 to 5 cm long by 0.5 to 15 mm wide mixed with
  • Smaller dark reddish-brown scales 5-15 mm long by 0.5 mm wide with spiny margins.

The frond lamina, up to 3.5 m long, is twice divided and sometimes 3 times at the base.
The primary leaflets, on short stalks, are up to 65 cm long and the secondary ones 12 cm.

The secondary, stalked leaflets are divided into about 15-20 segments up to 17 mm long with toothed edges.
The segments have wide bases forming wings on the midrib except for few a basal segments which have a short stalk.

The segments have a central vein and forked lateral ones.
Both sides of the leaflet midribs have some white, brown or reddish scales and hairs.

Sori, up to 1 mm across are in rows of up to 10, situated close to the midrib or half way to the segment edge.
There is no indusium but red, white or brown scales with bristles encircle the base of the sori.

J.F.