''Pennantia baylisiana'', commonly known as Three Kings kaikōmako or (
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 C ...
), is a species of
plant
Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclud ...
in the family
Pennantiaceae
''Pennantia'' is the sole genus in the plant family Pennantiaceae. In older classifications, it was placed in the family Icacinaceae. Most authorities have recognised three or four species, depending on whether they recognised ''Pennantia baylis ...
(
Icacinaceae
The Icacinaceae, also called the white pear family, are a family of flowering plants,"Icacinaceae" At: Angiosperm Phylogeny Website At: Missouri Botanical Garden Website (see ''External links'' below).
consisting of trees, shrubs, and lianas, pri ...
in older classifications). It is
endemic
Endemism is the state of a species being found 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 found elsew ...
to
Manawatāwhi / Three Kings Islands
The Manawatāwhi / Three Kings Islands (sometimes just known collectively by the Māori name for the largest island, Manawatāwhi) are a group of 13 uninhabited islands about northwest of Cape Reinga / Te Rerenga Wairua, New Zealand, where th ...
, around northwest of
Cape Reinga
, type =Cape
, photo = Cape Reinga, Northland, New Zealand, October 2007.jpg
, photo_width = 270px
, photo_alt =
, photo_caption =
, map = New Zealand
, map_width = 270px
...
, New Zealand. At the time of its discovery just
one plant remained. This single tree grows on a scree slope inaccessible to browsing goats, and has been called "the world's loneliest tree".
The species was discovered in 1945 by botanist
Geoff Baylis
Geoffrey Thomas Sandford Baylis (24 November 1913 – 31 December 2003) was a New Zealand botanist and Emeritus Professor specialising in plant pathology and mycorrhiza. He was employed at the University of Otago for 34 years undertaking rese ...
and described in 1948, although it took decades before it was it was fully accepted as a distinct species of ''
Pennantia
''Pennantia'' is the sole genus in the plant family Pennantiaceae. In older classifications, it was placed in the family Icacinaceae. Most authorities have recognised three or four species, depending on whether they recognised '' Pennantia bayli ...
''. Although the only wild tree is female, it was successfully propagated from cuttings in the 1950s, one of which was induced to self-pollinate in 1985. Subsequent seed-grown plants have themselves set seeds, and the species has been replanted on the island, the adjoining mainland, and in public and private gardens around New Zealand.
Description
''Pennantia baylisiana'' is a shrubby, multi-trunked tree with a broad crown, unlike the three other species in the genus ''
Pennantia
''Pennantia'' is the sole genus in the plant family Pennantiaceae. In older classifications, it was placed in the family Icacinaceae. Most authorities have recognised three or four species, depending on whether they recognised '' Pennantia bayli ...
''. It does not have a
divaricating
Divaricate means branching, or having separation or a degree of separation. The angle between branches is wide.
In botany
In botany, the term is often used to describe the branching pattern of plants. Plants are said to be divaricating when the ...
juvenile form, unlike the other New Zealand ''Pennantia'' species kaikōmako (''
P. corymbosa'').
It grows to a height of 5 m in the wild, though has been recorded reaching 8 m in cultivation. It has pale greyish-brown bark and branchlets that are covered with
lenticels
A lenticel is a porous tissue consisting of cells with large intercellular spaces in the periderm of the secondarily thickened organs and the bark of woody stems and roots of dicotyledonous flowering plants. It functions as a pore, providing a ...
.
It has leathery, green, egg-shaped alternate leaves around 12–16 by 7–10 cm. Adult leaves have smooth margins but young leaves are toothed. The leaves are large and flat in shade-grown plants, up to 20 by 10 cm, but notably curled along their sides – almost rolled – on branchlets exposed to sun and wind. They have distinctive hair-covered
domatia
A domatium (plural: domatia, from the Latin "domus", meaning home) is a tiny chamber that houses arthropods, produced by a plant.
Ideally domatia differ from galls in that they are produced by the plant rather than being induced by their inhabi ...
on the underside, at the junction of the midrib and secondary veins, and are suspended from 2.5 cm long
petioles.
Flowering occurs from October to November, producing 1.5 by 1.5 mm greenish-white flowers in
panicles
A panicle is a much-branched inflorescence. (softcover ). Some authors distinguish it from a compound spike inflorescence, by requiring that the flowers (and fruit) be pedicellate (having a single stem per flower). The branches of a panicle are o ...
with 2.6 mm petals. Flowers usually arise on woody branches, though some are terminal. The
stamen
The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10
Morphology and terminology
A stamen typically consists of a stalk called the filame ...
is made up of a 1–1.4 mm long anther on top of a 1.5 mm long filament, though the pollen is usually sterile. It has a 2.8 by 2 mm cylindrical ovary with a stigmatic ring 1.5–1.8 mm in diameter. Fruiting is from January through to April in cultivated plants yielding 10 by 4.5 mm
ellipsoid
An ellipsoid is a surface that may be obtained from a sphere by deforming it by means of directional scalings, or more generally, of an affine transformation.
An ellipsoid is a quadric surface; that is, a surface that may be defined as the ...
fruit. Mature fruit are purple to black and have a single hard 9 by 3.5 mm seed.
Its chromosome number is 2''n'' = 50, as with ''P. corymbosa''.
File:Pennantia baylisiana.jpg, Foliage, showing distinctive rolled leaves
File:Pennantia baylisiana kz3.jpg, Flowers in bud
File:Three Kings Kaikomako - Pennantia baylisiana.jpg, Foliage, from beneath
Discovery
![Pennantia baylisiana (AM AK22872)](https://upload.wikimedia.org/wikipedia/commons/2/24/Pennantia_baylisiana_%28AM_AK22872%29.jpg)
''Pennantia baylisiana'' was discovered by New Zealand botanist
Geoff Baylis
Geoffrey Thomas Sandford Baylis (24 November 1913 – 31 December 2003) was a New Zealand botanist and Emeritus Professor specialising in plant pathology and mycorrhiza. He was employed at the University of Otago for 34 years undertaking rese ...
in 1945 when he visited Great Island, the largest of the
Manawatāwhi / Three Kings Islands
The Manawatāwhi / Three Kings Islands (sometimes just known collectively by the Māori name for the largest island, Manawatāwhi) are a group of 13 uninhabited islands about northwest of Cape Reinga / Te Rerenga Wairua, New Zealand, where th ...
, on a botanical expedition. The Three Kings are located around northwest of
Cape Reinga
, type =Cape
, photo = Cape Reinga, Northland, New Zealand, October 2007.jpg
, photo_width = 270px
, photo_alt =
, photo_caption =
, map = New Zealand
, map_width = 270px
...
, and at the time were relatively unknown botanically, with the only collecting expeditions in 1887 and 1889 (both by
Thomas Cheeseman
Thomas Frederick Cheeseman (8 June 184515 October 1923) was a New Zealand botanist. He was also a naturalist who had wide-ranging interests, such that he even described a few species of sea slugs (marine gastropod molluscs).
Biography
Chees ...
, director of Auckland Museum, who had only a few hours ashore), 1928, and 1934. Baylis spent a week on the island in November–December 1945, and collected samples of 83 species of plants for Auckland Museum.
By this time wild goats had eaten the place out. Part was closely browsed grass but most was kanuka forest or scrub. Cheeseman's novelties survived in small numbers beyond browse range. It was easy to see that the grassland offered nothing new, but the kanuka canopy was broken here and there by other textures and shades of green. I located these places by climbing trees at every vantage point and reached them deviously via bluffs and screes since except in the main valley they were, even for goats, a bit inaccessible.
Four of Baylis's discoveries were new to science, including ''Suttonia dentata'' (now ''
Myrsine oliveri''), ''
Tecomanthe speciosa'' (which like ''P. baylisiana'' was represented by a single living individual), and ''
Brachyglottis arborescens.''
After collecting the latter two, he describes coming across ''P. baylisiana'':
The last little grove that I investigated lay near the highest point of the island down a scree of boulders about 200m above the sea. I was drawn to it by what looked like a karaka. I was soon gazing upon it in disbelief since a third find seemed too much to expect. But this was no karaka – its leaves were larger and recurved strongly in the sun, its bunches of small green flowers sprang from the bare branches below the leaves and there were no big berries – indeed none at all.
He noted that the 15-foot tree was living on a seaward scree slope of greywacke boulders at an altitude of 700 feet, with pōhutukawa (''
Meterosideros excelsa''), kānuka ''(
Kunzea ericoides
''Kunzea ericoides'', commonly known as kānuka, kanuka, white tea-tree or burgan, is a tree or shrub in the myrtle family, Myrtaceae and is endemic to New Zealand. It has white or pink flowers similar to those of ''Leptospermum'' and from its ...
''), coastal maire (''
Nestegis apetala
''Nestegis apetala'' is a small tree native to northern New Zealand and to Norfolk Island. The common names in New Zealand are coastal maire or broad-leaved maire. On Norfolk Island, the common name is ironwood. The species name ''apetala'' ref ...
''), and whārangi (''
Melicope ternata
''Melicope ternata'', commonly known as wharangi, is a coastal shrub or small tree in the family Rutaceae that is native to New Zealand.
''Melicope ternata'' has glossy, green, trifoliate foliage and can grow into a tree 8 metres tall. It is fou ...
'') growing nearby. The tree was forked at the base and badly eaten by insects.
Baylis collected the
holotype
A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...
specimen of ''P. baylisiana'' (housed in
Auckland War Memorial Museum
The Auckland War Memorial Museum Tāmaki Paenga Hira (or simply the Auckland Museum) is one of New Zealand's most important museums and war memorials. Its collections concentrate on New Zealand history (and especially the history of the Aucklan ...
) on 2 December 1945.
Taxonomy
The species was described by Director of Auckland Museum
Walter Oliver
Walter Reginald Brook Oliver (7 September 1883 – 16 May 1957) was a New Zealand naturalist, ornithologist, malacologist, and museum curator.
Biography
Born in Launceston, Tasmania, Oliver emigrated with his family to New Zealand in 1896, set ...
in 1948. Oliver noted its resemblance to the genus ''
Corynocarpus'', which includes the New Zealand species karaka (''
Corynocarpus laevigatus
Karaka or New Zealand laurel (''Corynocarpus laevigatus'') is an evergreen tree of the family Corynocarpaceae endemic to New Zealand. It is common throughout the North and South Islands to Banks Peninsula (43°45′S) and Okarito (43°20′S) ...
''). ''Corynocarpus'' had until recently been considered to be in the family
Anacardiaceae
The Anacardiaceae, commonly known as the cashew family or sumac family, are a family of flowering plants, including about 83 genera with about 860 known species. Members of the Anacardiaceae bear fruits that are drupes and in some cases produce ...
, which is where Oliver placed this species, erecting a new genus ''Plectomirtha'' to contain it and giving it the
specific epithet
In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...
''baylisiana'' in recognition of the plant’s discoverer Geoff Baylis.
Oliver had not noticed the plant's similarity to the mainland New Zealand species kaikōmako (''
Pennantia corymbosa''); indeed, Sleumer in 1970 working from
herbarium
A herbarium (plural: herbaria) is a collection of preserved plant specimens and associated data used for scientific study.
The specimens may be whole plants or plant parts; these will usually be in dried form mounted on a sheet of paper (called ...
sheets proposed that the species not only belonged in the genus ''
Pennantia
''Pennantia'' is the sole genus in the plant family Pennantiaceae. In older classifications, it was placed in the family Icacinaceae. Most authorities have recognised three or four species, depending on whether they recognised '' Pennantia bayli ...
'', but was a synonym of
''P. endlicheri'' from
Norfolk Island
Norfolk Island (, ; Norfuk: ''Norf'k Ailen'') is an external territory of Australia located in the Pacific Ocean between New Zealand and New Caledonia, directly east of Australia's Evans Head and about from Lord Howe Island. Together with ...
which has similarly-large leaves. Baylis disagreed and maintained that ''P. baylisiana'' was a distinct species of ''Pennantia'', citing amongst other features its distinctive thickened and curled leaves, its thicker twigs, and panicles of flowers that mostly arose directly from the trunk rather than at the ends of branches (known as
cauliflory
Cauliflory is a botanical term referring to plants that flower and fruit from their main stems or woody trunks, rather than from new growth and shoots. This can allow trees to be pollinated or have their seeds dispersed by animals that climb o ...
). In 1977 he wrote:
It is not often that a botanist can decently attach his own name to a plant, but this paper aims to establish that the Three Kings tree is like most of the Three Kings endemics, the remains of a distinctive population.
The importance of this distinction rested on the fact that only a single female tree remained on the Three Kings. If it and the Norfolk Island ''Pennantia'' were the same species it could be hybridised with Norfolk Island male trees and create a new and genetically variable population.
In their 2002 revision of the genus ''Pennantia'', Gardner and de Lange concluded that ''P. baylisiana'' was indeed distinct from ''P. endlicheri'', having large, hairy domatia at the junction of leaf midrib and lateral veins (''P. endlicheri''
's are small and hairless), a different arrangement of the stigmas, and thicker pedicels.
A DNA phylogeny confirmed its distinctiveness, placing ''P. corymbosa'' and ''P. endlicheri'' as each other's closest relatives and ''P. baylisiana'' as sister taxon to both of them, the three species diverging some time within the last 9 million years.
Distribution
It is only found in the wild on Manawatāwhi / Three Kings Islands, an island chain north-west of the top of the North Island, on Great Island (Manawatāwhi). There is only one tree known in the wild; a female growing above a cliff on the northern face of Great Island.
This tree has been called "the loneliest tree".
The species has now been propagated by plantings in various garden locations in New Zealand, including
Otari-Wilton's Bush
Otari-Wilton's Bush is a native botanic garden and forest reserve located in Wilton in Wellington, New Zealand.
It is the only public botanic garden that is dedicated solely to the native plants of New Zealand.
Overview
Otari-Wilton's Bus ...
, and around 200 saplings have been planted in
Northland.
Conservation
Manawatāwhi / Great Island had been inhabited 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 C ...
for at least 200 years, during which time they farmed goats and pigs and cleared the forest – along the coast predominantly puka, ''
Meryta sinclairii
''Meryta sinclairii'', the puka or pukanui, is a large-leaved evergreen tree endemic to New Zealand that grows to about 8 m tall, with the distinctly tropical appearance typical of the genus. There are about 27 species of ''Meryta'', all small ...
–'' from almost all cultivatable land. Māori occupation ended around 1840, and all livestock seem to have been removed at that time. When Cheeseman landed in 1887, the island was almost covered with kānuka, and regenerating forest trees were plentiful (although ''Meryta sinclairii'' did not reappear until 1946, which led Baylis to speculate that some goats may still have been present and preventing this species from re-establishing).
The government survey party decided that Great Island needed to be stocked with animals that could feed shipwrecked sailors, so on Cheeseman's second collecting trip in 1889 four goats were released. They increased rapidly in numbers, stopping forest regeneration and almost driving some species to extinction. At the time Baylis visited in 1945, nearly 50 plant species had been driven locally extinct on Great Island, and others had been almost eliminated, with only a few or a single individual surviving in places inaccessible to goats.
In 1946 a Government shooting party was sent to the island and killed all 398 goats present.
This species is threatened by habitat loss. The one tree remaining in the wild at Three Kings Island is at significant risk from storm damage, droughts and senesence.
''P. baylisiana'' was previously recognised by
The Guinness Book of World Records
''Guinness World Records'', known from its inception in 1955 until 1999 as ''The Guinness Book of Records'' and in previous United States editions as ''The Guinness Book of World Records'', is a reference book published annually, listing world ...
as the rarest tree in the world.
After discovering the tree in 1945, Baylis brought its only sucker shoot back to Auckland, and planted it in his Dunedin garden, where it eventually took root.
Following his death, his colleagues continued to care for the seedling, and after around 40 years they noted that it had set seed. Attempts to root cuttings from the crown of the tree by both the
DSIR Department of Scientific and Industrial Research, abbreviated DSIR was the name of several British Empire organisations founded after the 1923 Imperial Conference to foster intra-Empire trade and development.
* Department of Scientific and Industria ...
Plant Diseases Division and the commercial
New Plymouth
New Plymouth ( mi, Ngāmotu) 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, Devon from where the first English settlers to New Plymouth migrated. ...
nursery
Duncan and Davies had failed. As Baylis later related,
n 1950I asked George Smith the chief propagator at New Plymouth what I might do to provide better cuttings. "Cut the tree down" he said, and while I shuddered at the thought he explained that he was confident about rooting shoots from the stump. But would there be any? Well, the tree had four trunks so I dared to sever one. A year later the shoots were there, the Naval launch on which I was a guest gave them a quick passage to New Plymouth which happened to be its next port and Mr Smith soon placed the survival of "''Plectomirtha''" beyond doubt.
Cuttings were raised for 20 years at the
Department of Scientific and Industrial Research Department of Scientific and Industrial Research, abbreviated DSIR was the name of several British Empire organisations founded after the 1923 Imperial Conference to foster intra-Empire trade and development.
* Department of Scientific and Industria ...
. Hardwood cuttings of ''P. baylisiana'' can take 10 months to root, and the young trees, which were clones of the single wild tree, often died in the first year.
From the 1970s onwards, cuttings from this generation of plants were propagated by specialist plant growers and made available to gardeners.
In cultivation the trees grow readily in sun or shade, and can tolerate wind and drought, and even light frost.
''P. baylisiana'' is
dioecious
Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproductio ...
, and the remaining wild tree was thought to be entirely female. In the late 1980s, fruit was found for the first time on the one tree remaining in the wild, indicating that on occasion viable pollen was produced and self-fertilisation could occur, a rare occurrence in dioecious plants. However, it was discovered that few of self-pollinated fruit were fertile (around 1 in 2000).
In 1985
Ross Beever from
Manaaki Whenua Landcare Research used plant hormone to produce viable pollen on a female tree in cultivation at Mt Albert Research Centre, using hand-pollination to achieve self-fertilisation. One the seedlings produced as a result, named "Martha", was naturally self-fertile and from the early 1990s produced a good amount of seed without hand-pollination, allowing many saplings to be grown.
These plants were generally self-fertile, taking four or five years to produce fruit and seed.
By 1998 hundreds of saplings had been grown from seed, but these were not immediately replanted on Great Island, for fear of introducing bacteria or fungal disease which could attack the remaining wild tree.
In 2010 the
Department of Conservation
An environmental ministry is a national or subnational government agency politically responsible for the environment and/or natural resources. Various other names are commonly used to identify such agencies, such as Ministry of the Environment ...
planted 1,600 ''P. baylisiana'' seeds from mainland fruit back on Great Island, after carefully treating them to avoid introducing pathogens.
In 2019, two hundred saplings raised by Manaaki Whenua Landcare Research were given to
Ngāti Kurī
Ngāti Kurī is a Māori iwi from Northland, New Zealand. The iwi is one of the five Muriwhenua iwi of the far north of the North Island. Ngāti Kurī trace their whakapapa (ancestry) back to Pōhurihanga, the captain of the waka (canoe) Kurahau ...
, a Māori
iwi
Iwi () are the largest social units in New Zealand Māori society. In Māori roughly means "people" or "nation", and is often translated as "tribe", or "a confederation of tribes". The word is both singular and plural in the Māori language, an ...
from Northland, whose traditional tribal area ( mi, rohe) includes the Three Kings Islands. These saplings have been planted around the Waiora marae at
Ngātaki, north of
Kaitaia
Kaitaia ( mi, Kaitāia) is a town in the Far North District of New Zealand, at the base of the Aupouri Peninsula, about 160 km northwest of Whangārei. It is the last major settlement on New Zealand State Highway 1, State Highway 1. Ahipara ...
.
References
External links
Kaikōmako manawa tāwhi (''Pennantia baylisiana'') returns to the Far North and Ngāti KuriVideo by Manaaki Whenua Landcare Research
*''Pennantia baylisiana'' discussed on
RNZ ''
Critter of the Week
''Critter of the Week'' is a weekly RNZ National programme about endangered and neglected native plants and animals of New Zealand.
Beginning in 2015, ''Critter of the Week'' is an approximately 15-minute discussion between Nicola Toki of the ...
''
10 January 2022Native tree saved from extinction, returned to iwi;
RNZ interview with Sheridan Waitai of
Ngāti Kurī
Ngāti Kurī is a Māori iwi from Northland, New Zealand. The iwi is one of the five Muriwhenua iwi of the far north of the North Island. Ngāti Kurī trace their whakapapa (ancestry) back to Pōhurihanga, the captain of the waka (canoe) Kurahau ...
, 13 August 2019
{{Authority control
Pennantiaceae
Flora of the North Island
Critically endangered plants
Three Kings Islands
Taxonomy articles created by Polbot
Endlings