Kingdom:Plantae
Division:Pteridophyta
Class:Marattiopsida
Order:Marattiales
Family:Marattiaceae
Genus:Ptisana
Species: P. salicina
Binomial name: Ptisana salicina
Synonyms: Marattia salicina, Marattia fraxinea, Marattia fraxinea sensu 
Common name:  King fern, para, tawhiti-para,  horseshoe fern.

Ptisana salicina is a species of fern native to New Zealand and the South Pacific. Large and robust with a distinctive tropical appearance, it has fronds up to 5 metres tall that arise from a starchy base that was a traditional food for the Maori. The green cane-like leaf stalks are 1 to 3 metres long. The young fronds are protected as they uncoil by a large ear-shaped basal lobe at the base. The glossy, dark green fronds are 4 metres, sometimes 5 metres long and 2 metres wide. The juvenile fronds are less robust and wilt quickly if exposed to sunlight.
King fern is in serious decline, seriously threatened throughout its range by feral and domestic cattle, wild pigs and goats. Large plants no longer exist except in areas where there has been rigorous control of animals.

Ptisana salicina covering a hillside at the Burgess Park, New Plymouth.
King fern Ptisana salicina Marattia salicina-001.JPG

Ptisana salicina  growing at the Rogan Street entrance to Pukekura Park
Ptisana salicina King Fern .JPG

Ptisana salicina king fern-1.JPG

New frond developing
New frond of Ptisana salicina king fern 2-3.JPG

Underside of frond
Ptisana salicina king fern-2.JPG

Ptisana salicina king fern-4.JPG

Close up of King fern sori
King fern sori Ptisana salicina-1.jpg

Photo of Ptisana salicina frond bracts. The bracts at the base of the frond were a prized Maori delicacy.
Ptisana salicina King fern-1.JPG

Thanks to Wikipedia for text and information:

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