Cyathea dealbata

From Wikipedia, the free encyclopedia

Silver Fern
Frond, showing silver underside
Frond, showing silver underside
Conservation status
Secure
Scientific classification
Kingdom: Plantae
Division: Pteridophyta
Order: Cyatheales
Family: Cyatheaceae
Genus: Cyathea
Subgenus: Cyathea
Section: Alsophila
Species: C. dealbata
Binomial name
Cyathea dealbata
(G. Forster) Swartz, 1801
Synonyms
  • Polypodium dealbatum G. Forster, 1786
  • Cyathea tricolor Colenso, 1883
  • Alsophila tricolor (Colenso) Tryon, 1970

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.[1]

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[2] (around 5 - 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-drained humus, 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.

[edit] Silver fern in culture

[edit] References

  1. ^ The Māori word ponga (IPA:'poŋa) has been borrowed into New Zealand English as a generic term for tree ferns. It is also used to refer to tree fern logs when used for landscaping purposes. English speakers generally pronounce the word as punga (IPA:'pʌŋə).
  2. ^ Parsons, Stuart; et al. (2006). Biology Aotearoa. Pearson Education New Zealand. ISBN 1 877268 00 3.