Pōhutukawa (''Metrosideros excelsa''), also known as the New Zealand Christmas tree, or iron tree, is a coastal

evergreen In botany, an evergreen is a plant which has Leaf, foliage that remains green and functional throughout the year. This contrasts with deciduous plants, which lose their foliage completely during the winter or dry season. Consisting of many diffe ...

tree in the myrtle family,

Myrtaceae Myrtaceae (), the myrtle family, is a family of dicotyledonous plants placed within the order Myrtales. Myrtle, pōhutukawa, bay rum tree, clove, guava, acca (feijoa), allspice, and eucalyptus are some notable members of this group. All ...

, that produces a brilliant display of red (or occasionally orange, yellow or white) flowers, each consisting of a mass of

stamen The stamen (: stamina or stamens) is a part consisting of the male reproductive organs of a flower. Collectively, the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament ...

s. The pōhutukawa is one of twelve ''

Metrosideros ''Metrosideros'' is a genus of approximately 60 trees, shrubs, and vines in the family Myrtaceae, mostly found in the Pacific region. Most of the tree forms are small, but some are exceptionally large, the New Zealand species in particular. The ...

'' species

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to New Zealand. Renowned for its vibrant colour and its ability to survive even perched on rocky, precarious cliffs, it has found an important place in New Zealand culture for its strength and beauty, and is regarded as a chiefly tree (') by

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the Co ...

Etymology

The generic name ''Metrosideros'' derives from the

Ancient Greek Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...

' or '

heartwood Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin t ...

' and ' or 'iron'. The

species name In taxonomy, binomial nomenclature ("two-term naming system"), also called binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, altho ...

''excelsa'' is from

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

', 'highest, sublime'. ' is a Māori word. Its closest equivalent in other Polynesian languages is the Cook Island Māori word ', referring to a coastal shrub with white berries, ''

Sophora tomentosa ''Sophora'' is a genus of about 45 species of small trees and shrubs in the pea family Fabaceae. The species have a pantropical distribution. The generic name is derived from ''sophera'', an Arabic name for a pea-flowered tree. The genus formerl ...

''.Polynesian Lexicon Project Online, entry *poo-futu-kawa
The ''-hutu-'' part of the word comes from ', the Polynesian name for the fish-poison tree (''

Barringtonia asiatica ''Barringtonia asiatica'', known variously as fish poison tree, putat and beach Barrintonia among other names, is a species of plants in the brazil nut family Lecythidaceae. It is native to coastal habitats from Tanzania and Madagascar in the ...

''; compare with and ), which has flowers similar to those of the pōhutukawa.

Description

Pōhutukawa grow up to high, with a spreading, dome-like form. They usually grow as a multi-trunked spreading tree. Their trunks and branches are sometimes festooned with matted, fibrous

aerial root Aerial roots are Root, roots growing above the ground. They are often Plant development#Adventitious structures, adventitious, i.e. formed from nonroot tissue. They are found in diverse plant species, including epiphytes such as orchids ('' ...

s. The oblong, leathery leaves are covered in dense white hairs underneath. The tree flowers from November to January with a peak in early summer (mid to late December), with brilliant crimson flowers covering the tree, hence the nickname New Zealand Christmas tree. The first published reference to pōhutakawa as a Christmas tree was in 1857, in a newspaper report of a feast held by Eruera Patuone. There is variation between individual trees in the timing of flowering, and in the shade and brightness of the flowers. In isolated populations

genetic drift Genetic drift, also known as random genetic drift, allelic drift or the Wright effect, is the change in the Allele frequency, frequency of an existing gene variant (allele) in a population due to random chance. Genetic drift may cause gene va ...

has resulted in local variation: many of the trees growing around the Rotorua lakes produce pink-shaded flowers, and the yellow-flowered

cultivar A cultivar is a kind of Horticulture, cultivated plant that people have selected for desired phenotypic trait, traits and which retains those traits when Plant propagation, propagated. Methods used to propagate cultivars include division, root a ...

'Aurea' descends from a pair discovered in 1940 on Mōtītī Island in the

Bay of Plenty The Bay of Plenty () is a large bight (geography), bight along the northern coast of New Zealand's North Island. It stretches from the Coromandel Peninsula in the west to Cape Runaway in the east. Called ''Te Moana-a-Toitehuatahi'' (the Ocean ...

Distribution

The pōhutukawa's natural range is the coastal regions of the

North Island The North Island ( , 'the fish of Māui', historically New Ulster) is one of the two main islands of New Zealand, islands of New Zealand, separated from the larger but less populous South Island by Cook Strait. With an area of , it is the List ...

of New Zealand, north of a line stretching from

New Plymouth New Plymouth () is the major city of the Taranaki region on the west coast of the North Island of New Zealand. It is named after the English city of Plymouth, in Devon, from where the first English settlers to New Plymouth migrated. The New Pl ...

(39° S) to Gisborne (38° S), where it once formed a continuous coastal fringe. By the 1990s, pastoral farming and introduced pests had reduced pōhutukawa forests by over 90%. It also occurs naturally on the shores of lakes in the

Rotorua Rotorua () is a city in the Bay of Plenty region of New Zealand's North Island. It is sited on the southern shores of Lake Rotorua, from which it takes its name. It is the seat of the Rotorua Lakes District, a territorial authorities of New Zea ...

area and in

Abel Tasman National Park Abel Tasman National Park is a national park at the north end of New Zealand's South Island. It covers of land between Golden Bay / Mohua and Tasman Bay / Te Tai-o-Aorere, making it the smallest of National parks of New Zealand, New Zealand's ...

at the top of South Island. The tree is renowned as a cliff-dweller, able to maintain a hold in precarious, near-vertical situations. Like its

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

an relative the ' ('' M. polymorpha''), the pōhutukawa has been shown to be efficient in the colonisation of

lava plain A lava field, sometimes called a lava bed, is a large, mostly flat area of lava flows. Such features are generally composed of highly fluid basalt lava, and can extend for tens or hundreds of kilometers across the underlying terrain. Morph ...

s – notably on Rangitoto, a volcanic island in the Hauraki Gulf.

Conservation

In New Zealand, pōhutukawa are under threat from browsing by the introduced

common brushtail possum The common brushtail possum (''Trichosurus vulpecula'', from the Ancient Greek, Greek for "furry tailed" and the Latin for "little fox", previously in the genus ''Phalangista'') is a nocturnal, semiarboreal marsupial of the family Phalangeridae ...

which strips the tree of its leaves. A charitable conservation trust,

Project Crimson __NOTOC__ Project Crimson is a conservation initiative to promote the protection of the pōhutukawa and the rātā which are under threat due to browsing by the introduced common brushtail possum. The vision of the project is to "enable pōhutu ...

, has the aim of reversing the decline of the pōhutukawa and other ''Metrosideros'' species – its mission statement is "to enable pōhutukawa and rata to flourish again in their natural habitat as icons in the hearts and minds of all New Zealanders".

Uses

Pōhutukawa wood is dense, strong and highly figured. Māori used it for beaters and other small, heavy items. It was frequently used in shipbuilding, since the naturally curvy shapes made strong

knees In humans and other primates, the knee joins the thigh with the leg and consists of two joints: one between the femur and tibia (tibiofemoral joint), and one between the femur and patella (patellofemoral joint). It is the largest joint in the hu ...

. Extracts are used in traditional Māori healing for the treatment of diarrhoea, dysentery, sore throat and wounds.

Cultivation

Pōhutukawa are popular in cultivation, and there are fine examples in most

coastal cities. Vigorous and easy to grow, the tree flourishes well south of its natural range, and has naturalised in the

Wellington Wellington is the capital city of New Zealand. It is located at the south-western tip of the North Island, between Cook Strait and the Remutaka Range. Wellington is the third-largest city in New Zealand (second largest in the North Island ...

area and in the north of the

South Island The South Island ( , 'the waters of Pounamu, Greenstone') is the largest of the three major islands of New Zealand by surface area, the others being the smaller but more populous North Island and Stewart Island. It is bordered to the north by ...

. It has also naturalised on

Norfolk Island Norfolk Island ( , ; ) is an States and territories of Australia, external territory of Australia located in the Pacific Ocean between New Zealand and New Caledonia, directly east of Australia's Evans Head, New South Wales, Evans Head and a ...

to the north. Pōhutukawa have been introduced to other countries with mild-to-warm climates, including south-eastern Australia, where it is naturalising on coastal cliffs near

Sydney Sydney is the capital city of the States and territories of Australia, state of New South Wales and the List of cities in Australia by population, most populous city in Australia. Located on Australia's east coast, the metropolis surrounds Syd ...

. In coastal

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

, it is a popular street and lawn tree, but has caused concern in

San Francisco San Francisco, officially the City and County of San Francisco, is a commercial, Financial District, San Francisco, financial, and Culture of San Francisco, cultural center of Northern California. With a population of 827,526 residents as of ...

where its root systems are blamed for destroying sewer lines and sidewalks. In parts of

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

, pōhutukawa grow so well that they are regarded as an

invasive species An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...

. The Spanish city of

A Coruña A Coruña (; ; also informally called just Coruña; historical English: Corunna or The Groyne) is a city and municipality in Galicia, Spain. It is Galicia's second largest city, behind Vigo. The city is the provincial capital of the province ...

has adopted the pōhutukawa as a floral emblem. At least 39

s of pōhutukawa have been released. Duncan & Davies nurseries were a leading force in the mid-20th century, while the late Graeme Platt has been responsible for 16 different cultivars so far, including a rare white-flowering tree. Cultivars include:

Iconic pōhutukawa

A giant pōhutukawa at

Te Araroa Te Araroa (The Long Pathway) is New Zealand's long distance tramping route, stretching circa along the length of the country's two main islands from Cape Reinga to Bluff. Officially opened in 2011, it is made up of a mixture of previously m ...

on the East Coast is reputed to be the largest in the country, with a height of 20 metres and a spread of . A pōhutukawa tree with an estimated age of 180 years known as 'Te Hā' is fully established at an Auckland City park. 'Te Hā' is the largest urban specimen in the country. Plans to build a monument in honour of victims of the Erebus Disaster in proximity to the tree activated significant local opposition in 2021.

References

External links

* *
Rare Metrosideros E. Alley
at Sao Miguel Island, Azores, where it grows faster and larger than in its native habitat {{Taxonbar, from=Q311747 Metrosideros Trees of New Zealand Trees of mild maritime climate Endemic flora of New Zealand Plants used in traditional Māori medicine