Kingdom: Plantae
(Unranked): Angiosperms
(Unranked): Monocots 
(Unranked): Commelinids
Order: Arecales
Family: Arecaceae
Subtribe: Rhopalostylidinae
Genus: Rhopalostylis
Species: R. baueri
Binomial name: Rhopalostylis baueri
Synonyms: Rhopalostylis cheesemanii, R. baueri var. cheesemanii,
Common names on Norfolk Island are Norfolk Island Palm and Niau.
Common names on the Kermadec Islands: Kermadec nikau and Raoul Island Palm 

Rhopalostylis baueri is a species of palm native to Norfolk Island (Australia) and to the Kermadec Islands (New Zealand). On RaoulIsland in the Kemadecs, though always abundant, the palm has, following the successful eradication of rats four years ago has greatly expanded its range. On Norfolk Island, it now occupies a small range in the centre of the island near the National Park, where the species is somewhat threatened by rats that eat the fruit and young seedlings. It is rare elsewhere on the island.
Rhopalostylis baueri reaches 10 m or more in height. The pinnate leaves are 3 to 4 m long, on a stout, erect petiole (leaf stem) approximately 20 cm long. The crown shaft is 50-60 cm long. The inflorescence is 30 50 cm long and has from 50 to 60 fairly stout branches. The fruits are green at first, turning a bright red when ripe, and are a favourite food of the endangered Norfolk Island Parakeet. The growing tip of the palm was used by early settlers as a vegetable and is said to have tasted like a nut when raw and like an artichoke bottom when boiled. It is much faster growing than the New Zealand nikau, Rhopalostylis sapida.
There is a Rhopalostylis bauer which is on the notable tree list 2002 beside the Cricket Pavilion at Pukekura Park.
Download pdf on that tree (  )

For more details on Rhopalostylis baueri visit: http://www.nzpcn.org.nz/flora_details.asp? ID=670

Photographed at Pukekura Park, New Plymouth.
Rhopalostylis baueri-002.JPG

Rhopalostylis baueri-001.JPG

Rhopalostylis baueri-003.JPG

Photo late August of green and the ripe red fruits.
Rhopalostylis baueri Kemadec Island nikau.JPG

Photographs below of a juvenile palm were taken at Otari Native Botanic Garden and Wilton's Bush Reserve. Wellington.
Rhopalostylis baueri Kermadec nikau Raoul Island palm-001.JPG

Closeup of the fronds.
Rhopalostylis baueri Kermadec nikau Raoul Island palm-002.JPG

Thanks to Wikipedia for text and information:

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