In most places, 'Ti' is part of their name - indicating that knowledge of these trees has been vital and carried widely around the Pacific.
Maori brought at least one species over, and found several more when they got here. In some parts, they selectively bred and cultivated them.
The most widespread of the Cordylines here is the native Ti kouka, or Cordyline australis, pretty much a national icon.
There's a great run-down, with photos, of the different species of Cordyline in New Zealand, here at The Bushman's Friend.
Cordylines as food
Ti kouka, along with others in the genus, provides a quick meal up the top, and a larger one, requiring a lot more prep, down the bottom.
If you take a leaf head and peel back the tough outer leaves, inside is a paler shoot and heart - with a delicious mix of sweet and bitter tastes. Trial and error during cooking will tell you how far you need to peel back the leaves till you find the tender shooting ones. (Better to strip away too few than too many to start with.)
Cook for 6 minutes or less, depending on its size, then treat it like an artichoke heart. I hope to put up a photo next time I do this!
You can boil them or bake them. If you throw them in with some baked veges, put them in towards the end, when there's about 10 mins left to go.
The inner trunk and the tap root of younger, smaller trees can be stripped, dried and baked, then made into a sugary, high-carb paste or meal.
Cordylines as medicine
Maori boiled the leaves up as a tea - a treatment for dysentry, and also a topical wash for wounds.
Cordylines as fibre and kindling
The leaves are tougher and more weatherproof than harakeke leaves. All around the Pacific they've been used to thatch roofs, and made into sandals, traps, mats, and more.
Old cabbage tree leaves can be folded or bundled up and make great kindling for your fire - catching alight fast. (The drier the better, but green ones burn too.)
The future of Cordylines in New Zealand
Grazing animals, and a bacterial infection called 'Sudden Decline', both threaten cabbage trees to some extent these days. If you scroll down, this page on the DoC website has good info about it.
Sustainable harvesting is all-important - growing your own, best of all. Cordylines need sun, but grow easily in all sorts of soils.
Above photo of Ti kouka courtesy of Wikimedia Commons.
