Cyathea dealbata, or the silver tree fern or silver fern (kaponga or ponga in the Māori language), is a species of medium-sized tree fern, endemic to New Zealand. It is a symbol commonly associated with the country both overseas and by New Zealanders themselves.
This fern is known to grow to heights of 10 m or more (though it occasionally takes a rare creeping form). The crown is dense, and the fronds tend to be about 4 m long and have a silver-white colouration on the undersides. This distinctive silver colouration has made them useful for laying along tracks for night walking. The scales are a dark brown and are often twisted and glossy.
Arriving relatively late in New Zealand’s history during the Pliocene epoch(around 5.0–1.8 million years ago), the silver fern occurs on the main islands of New Zealand and on the Chatham Islands to the east, mostly in the subcanopy areas of drier forests and in open scrub. It is known to grow well in well-drainedhumus, and once established, it will tolerate drier conditions. It does best when sheltered from winds and should be protected from frost. It does not grow under the dense canopy of mature forests.