Astelia trinervia (Kauri grass)

Kingdom: Plantae
(Unranked): Angiosperms
(Unranked): Monocots
Class: Magnoliopsida
Order: Asparagales
Family: Asteliaceae
Genus: Astelia
Species: A. trinervia
Binomial name: Astelia trinervia 
Common name: Kauri grass

Astelia trinervia is a slow-growing rhizomatous tufted herbaceous monocotyledon perennial and is the tallest of the New Zealand native Astelias growing to a height of 2.5m with a width of 2m. It is usually terrestrial but occasionally will grow as a low epiphyte.
In the North Island, it is common from Te Paki (the northernmost tip of the North Island) to near Awakino (100 km northeast of New Plymouth) in the west and Tauranga in the east. In the South Island known only from North West Nelson.
It is a common constituent of kauri forest of Northern New Zealand as implied by its common name.
It bears inflorescences of small red/pink flowers in autumn/early winter and these develop into red berries. Seed dispersal is by birds.
The Maori used the leaves for thatching.

These photos in Otari-Wilton's Bush Wellington New Zealand
Astelia trinervia Kauri grass-001.JPG 

The top surface of a leaf.
Astelia trinervia Kauri grass-002.JPG

The underside of a leaf
Astelia trinervia Kauri grass-003.JPG

Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/