Jump to content

Karaka (tree)

From Wikipedia, the free encyclopedia
(Redirected from Corynocarpus laevigatus)

Karaka
A mature tree in Glendowie
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Cucurbitales
Family: Corynocarpaceae
Genus: Corynocarpus
Species:
C. laevigatus
Binomial name
Corynocarpus laevigatus

Karaka or New Zealand laurel (Corynocarpus laevigatus) is a medium-sized evergreen tree in the Corynocarpaceae family. It is endemic to New Zealand and is common throughout the North Island and less common in the South Island. Karaka are also found on the Chatham Islands, Kermadec Islands, and the Three Kings Islands. It is mostly a coastal tree, though in the North Island, it can also be found in lowland inland forests.

It grows to heights up to 15–20 m (49–66 ft) and has a stout trunk up to 60 cm (24 in) in diameter. Its leaves are coriaceous, dark to bright green in colour and up to 15–30 cm (5.9–11.8 in) long and its orange-coloured fruit is 30–40 mm (1.2–1.6 in) in length. Karaka is a valuable food source for the kererū (Hemiphaga novaeseelandiae) and the Chatham Islands pigeon (Hemiphaga chathamensis). It is naturalised and considered an invasive species in several Hawaiian islands and is mostly found on the island of Kauai. Karaka is also grown in Southern California.

Considered a taonga (cultural treasure) amongst the Māori and Moriori peoples. On the Chatham Islands, carvings of Moriori ancestors were carved on to karaka trees (known as rākau momori) are considered internationally significant and unique to their culture. An exoplanet originally named HD 137388 was renamed to "Karaka" in 2019 in recognition of the tree's orange-coloured fruit.

Description

[edit]

Karaka is a medium-sized evergreen leafy canopy tree with erect spreading branches. It grows to heights up to 15–20 m (49–66 ft) and has a stout trunk usually up to 60 cm (24 in) in diameter. The largest trunk ever measured was 3 m (9.8 ft). Its leaves are coriaceous, dark to bright green in colour and up to 15–30 cm (5.9–11.8 in) long. Karaka starts flowering between August to November and each panicle may have up to 100–200 flowers.[1][2]

From August to November, large clusters of karaka produces stout, erect panicles of tiny flowers, greenish-yellow in colour and less than 0.5 cm (0.20 in) in diameter. The fruit it produces is 30–40 mm (1.2–1.6 in) in length, with pale yellow–orange coloured flesh,[3][4] it also contains a single poisonous seed. The fruit ripens between January and April and the seeds are mostly dispersed by columbiform birds (such as the kererū) which feeds on its fruit.[5][2]

Taxonomy

[edit]

Karaka (Corynocarpus laevigatus) is a unique medium-sized tree endemic to New Zealand, unlikely to be mistaken for any other native, foreign, or naturalised tree. It can be easily identified by its orange drupes and its leathery, dark green leaves.[6] Karaka is in the Corynocarpaceae family and includes four other species in the genus; (C. similis) in Vanuatu, (C. cribbianus) in the Solomon Islands, North Eastern Queensland and Vanuatu; (C. dissimilis) in New Caledonia; and (C. rupestris) in the Australian states of New South Wales and Queensland.[4]

Corynocarpaceae may have originated from a Paleotropical centre, then two separate radiations into colder climates. In the first, C. cribbianus and C. rupestris were found in Australia through New Guinea, while in the second, C. dissimilis, C. similis, and C. laevigatus were found in New Caledonia, which led to New Zealand. Fossilised Corynocarpus kernels from the early Miocene era were found at Landslip Hill in the Southland Region, indicating that the genus has a long history in New Zealand. It is possible that Corynocarpus spread from New Caledonia to New Zealand via land connections that existed in the mid-Tertiary era.[7]

Etymology

[edit]

The etymology of Corynocarpus translates to English to "club fruit", and the Latin specific epithet laevigatus translates to "smooth", in reference either to the fruit of the leaf or the skin. In the Māori language, karaka can either refer to the fruit of the tree or the tree itself. Karaka is also the Māori word for the colour orange.[8][3] In the Moriori language and on the Chatham Islands, the tree is known as kōpi. The tree is also known in English as the New Zealand laurel.[9]

Distribution

[edit]

Karaka is in large numbers throughout the North Island and South Island as far south as the Banks Peninsula on the east coast of the South Island and Greymouth (on the West Coast). Karaka is predominantly a coastal tree, though in the North Island, it can also be found in lowland inland forests.[10][11] Karaka is also found on the Chatham Islands, Kermadec Islands, and the Three Kings Islands.[7] It is generally accepted among sources that prior to Polynesian arrival of New Zealand, karaka were possibly limited to the northern North Island, even though it is now found on many offshore islands and the northern South Island.[12] If planted, karaka can survive as far south as Dunedin.[13]

It is naturalised and considered an invasive species in Hawaii. Karaka is also grown in Southern California.[14][15] Karaka was introduced to Hawaii for reforestation purposes and was first naturalised to Kauai in 1891, and is still commonly found throughout the island.[14][16]

Karaka is primarily naturalised on the island of Kauai. It is also found on the islands of Hawaii, Molokai, and Oahu.[17]

Ecology

[edit]
Karaka berries are a valuble food source for birds such as the kererū (pictured) and the parea.

Karaka is a valuable food source for New Zealand birds.[18] Such as the kererū (Hemiphaga novaeseelandiae) and the Chatham Islands pigeon or parea (Hemiphaga chathamensis) which are the only are the only extant bird species with a gape large enough to consume the fruits of karaka.[19] Centuries ago the fruits of the karaka would have been consumed by the extinct moa and possibly other large birds.[20]

A 1966 article from the Ornithological Society of New Zealand reported a New Zealand bellbird (Anthornis melanura) feeding on the sap from the bark of the karaka.[4] Other smaller New Zealand birds such as the North Island robin (Petroica longipes), silvereye (Zosterops lateralis) and whiteheads (Mohoua albicilla) are known to search around karaka trees for insects.[21]

The endocarp of karaka is usually nibbled by Polynesian rat (Rattus exulans), while the larger brown rats (Rattus norvegicus) occasionally chew open the endocarps. Both species consume the flesh of karaka.[4] Possums (an invasive species in New Zealand) are also known to consume the ripe flesh of karaka berries.[22]

Relationship with humans

[edit]

Cultivation

[edit]

Karaka is common in cultivation and widely available for sale both in New Zealand and elsewhere in the world.[5] It was one of the most grown food crops by pre-European Māori (alongside kūmara and aruhe),[23][24] they ate the drupe and seed after a long detoxification process.[25][24] Every autumn, Māori would collect the seeds dropped from the coastal karaka trees. The seeds would be placed in open-weave traditonal baskets (kete), washed in water to remove the outer pulp, afterwards baked and sun dried, a process that would remove toxicity from the seeds.[26]

In Māori culture

[edit]
A Moriori kōpi tree carving (rākau momori) in the Canterbury Museum

Māori primarily used karaka as a food source.[27] In Māori mythology, karaka is told to be from Hawaiki, an ancestral homeland for the Māori people.[13] In pre-European times, karaka was not known for its traditional healing value other than in its nutrition, though karaka did have other certain uses, with its underside of the leaf was used to extract an infection and its upper side was applied fresh to heal injured or infected skin.[28] The seeds of karaka were of great value to Māori and needed to be prepared before they could be safely consumed, while the flesh of the berry was consumed uncooked. The seeds are very poisonous and bitter in taste which had to be steamed properly in earth ovens (umu).[10][29] Karaka wood is also known to be used in constructing canoes (waka).[30]

In Moriori culture

[edit]

On the Chatham Islands, karaka has played a distinguished role in the history of Moriori people, the bark of these trees has been used for making dendroglyphs. A 2000 report by the Department of Conservation indicated the existence of 147 karaka trees with dendroglyphs on the Chatham Islands, though some may not have been authentically Moriori.[31][32] Karaka (or kōpi in Moriori) is considered a taonga (cultural treasure) amongst the Māori and Moriori peoples. Carvings embedded on to karaka trees are known in the Moriori language are known as rākau momori, which are usually depicting Moriori ancestors are considered internationally significant and unique to their culture. A rāhui has since been placed on the trees due to their delicate condition, and immediate measures are being taken to save the few carved trees that remain. Karaka wood was also utilised by the Moriori to smoke and preserve food.[33][34]

Recognition

[edit]

An exoplanet originally named HD 137388 was renamed to "Karaka" in 2019 in honour of the tree's orange fruit.[35] A small community 20 km (12 mi) west of Whanganui named Pākaraka is also named in honour of the tree and its name reflects the "abundance of karaka trees" that previously were situated here.[36] Karaka has also been recognised on New Zealand Post stamps with its penny postage stamps in 1967 depicting an image of karaka in the centre of the stamp.[37]

See also

[edit]

References

[edit]

Works cited

[edit]

Websites

  • De Lange, Peter (15 January 2012). "Corynocarpus laevigatus". New Zealand Plant Conservation Network. Archived from the original on 9 May 2024. Retrieved 5 November 2024.
  • Betson, Anne (18 December 2019). "Distant celestial objects now 'Kererū' and 'Karaka'". University of Auckland. Archived from the original on 1 March 2024. Retrieved 4 November 2024.
  • Gallaher, TJ; Brock, K; Kennedy, BH; Imada, CT; Imada, K; Walvoord, N (2020). "Corynocarpus laevigatus - Plants of Hawaiʻi". Plants of Hawaiʻi. Retrieved 5 November 2024.
  • Rapson, J. L. (24 November 2012). "Corynocarpus laevigatus (karaka)". CAB International. Retrieved 6 November 2024.
  • Tahana, Jamie (19 February 2022). "Pākaraka name returns to Whanganui village". Radio New Zealand. Archived from the original on 19 February 2022. Retrieved 4 November 2024.
  • Kerridge, Donna (14 February 2018). "How to prepare the delicious – but poisonous – karaka berry". The Spinoff. Archived from the original on 10 May 2024. Retrieved 4 November 2024.

Books

Journals

[edit]