Prumnopitys taxifolia

Prumnopitys taxifolia, commonly known as the mataī or black pine, is a species of tree in the family Podocarpaceae. It is a dioecious evergreen conifer reaching 30 metres (100 feet) in height, with a trunk up to 2 m (6 ft 7 in) in diameter, typically inhabiting lowland to montane forests. It is endemic to New Zealand; its range mainly covers the North and South Islands, it also occurs on Stewart Island, but is extremely uncommon there. P. taxifolia is profoundly heteroblastic; its young form is distinct and resembles a divaricating-wiry shrub, which may last for up to 60 years. It is unknown why P. taxifolia developed this characteristic. P. taxifolia has an average lifespan of 600 years, although it may live as long as 1000 years.

Prumnopitys taxifolia
A mature P. taxifolia specimen in Waikouaiti
Conservation status
Least Concern  (IUCN 3.1)
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Gymnospermae
Division:	Pinophyta
Class:	Pinopsida
Order:	Araucariales
Family:	Podocarpaceae
Genus:	Prumnopitys
Species:	P. taxifolia
Binomial name
Prumnopitys taxifolia (Banks & Sol. ex D. Don) de Laub.
Synonyms
Dacrydium taxifolium Lamb. Podocarpus spicatus R.Br. Dacrydium mai A.Cunn. Stachycarpus spicatus Tiegh. Prumnopitys taxifolia de Laub.

P. taxifolia was first described by the British botanist Aylmer Bourke Lambert in 1832. The fruits of P. taxifolia are dispersed by fruit-eating animals (frugivores), and the tree is pollinated by the wind. It is commonly found on mountain slopes in which it grows in fertile and well-drained soils, and can grow well in drier climates. P. taxifolia's timber is noted for its strength and durability, and was historically used for building bridges and houses, railway sleepers, and furniture-making. The conservation status of P. taxifolia was assessed by the IUCN Red List in 2013 as "Least Concern".

Description

Foliage of P. taxifolia

Prumnopitys taxifolia is a species of dioecious evergreen conifer in the family Podocarpaceae, reaching heights of 30 metres (100 feet) tall, with a trunk of up to 1–2 metres (3 feet 3 inches – 6 feet 7 inches) in diameter.^[1][2] Branches are initially ascending and eventually become spreading, forming a domed or rounded crown.^[3][4] The bark is thin and smooth (particularly on younger trees); it has spots, similar to hammer marks, which are red or purplish-brown in colour when fresh, weathering into a dark brown to black colour, and peeling freely into thick flakes. The outer bark itself can vary in colour from a dark brown to an almost black colour. The wood is very dense, hard, and a dark brown to rich yellow-brown colour.^[2][3] P. taxifolia has an average lifespan of 600 years, although it may live as long as 1000 years.^[5]

P. taxifolia's young form is distinct and exhibits prolific heteroblasty.^[6] Its young form, which resembles a tangled shrub, is so distinct that the first botanists in New Zealand initially thought they were separate species.^[6][7] Unlike the related miro (Pectinopitys ferruginea), P. taxifolia has a distinctive and long-lasting young stage, which is a tangle of slender, flexible, divaricating branchlets that are interspersed with a scattering of leaves. After several decades, the adult tree begins to grow out of the top of the young shrub and the divaricating branchlets will drop off.^[8] It is unknown why this species developed this characteristic; one possibility is that the tangled branches to create a warm temperature inside, hence the species could survive in colder climates, or it may serve as a defense against browsing animals.^[7][9] The young stage can last for up to 60 years.^[8]

Young leaves are 5–10 × 1–2 mm long and brown to pale yellow in colour, narrow and tapering, with a pointed tip, and can have long whip-like shoots. Adult leaves are 10–15 × 1–2 mm long, dark green in colour, glaucous, subdistichous and often apiculate in character.^[2][5] They generally have a broad shape, but can be more pectinate and linear in character, (6–)10–20 mm long, (1–)1.5–2 mm wide.^[3] Leaves are widest near the middle, with nearly parallel sides. The midrib is raised on a bluish-green surface, where there are waxy, pale bluish-green bands of stomata.^[5] The Canadian botanist, James Emory Eckenwalder, theorised that the leaves of P. taxifolia potentially contain unidentified physiologically active compounds.^[2][5]

Like all conifers, P. taxifolia does not produce flowers or true fruits, but instead produces pollen and seed in cones. The species is dioecious, with male and female reproductive structures on separate trees. The ovules are found on short axillary branches, with 3–10 per a 40 mm long spike.^[2] P. taxifolia's male pollen cones are found on nearly leafless lateral and axillary spikes near the ends of foliage branches. Each spike is yellow in colour, and can have up to 10–30 cones per spike, each 5–12 mm long and approximately 2 mm wide.^[10] The seed cones take 12–18 months to mature and are found throughout the year.^[2] They are round to oval in shape, fleshy, globe-shaped or nearly spherical, purplish-black in colour, and about 8–10 mm wide.^[10] P. taxifolia has a diploid chromosone count of 38.^[11]

Gallery

• 
  P. taxifolia has smooth brown bark, with hammer mark-like patterning throughout it.
• 
  P. taxifolia's purple-black-coloured globe-shaped drupes.
• 
  The pollen cones are 30–50 mm long, with up to 30 cones per spike.
• 
  P. taxifolia before exhibiting heteroblasty. It is a divarciating-wiry shrub.

Taxonomy

Classification

Sundacarpus amarus Prumnopitys andina Prumnopitys taxifolia Prumnopitys montana Pectinopitys ladei Pectinopitys ferruginea Pectinopitys ferruginoides

Cladogram depicting the relationships of the species within the genera Pectinopitys, Prumnopitys and Sundacarpus.[12]

P. taxifolia is a member of the genus Prumnopitys, which consists of five species across Australasia and South America.^[13] P. taxifolia is categorised in the subgenus Prumnopitys.^[13] In 2019, British botanist Chris Page transferred six species from Prumnopitys into a genus Page newly described as Pectinopitys. Page retained three species within the genus Prumnopitys, including P. taxifolia.^[14] He based his move on cladistic, morphological, and molecular analysis, concluding that Pectinopitys was distinct enough for it to be described as a new genus, rather than retaining it in Prumnopitys. Page also mentioned that Pectinopitys has a diploid chromosone count of 2n =  36, while Prumnopitys has a count of 2n = 38.^[15] Khan et al. (2022) revealed that Prumnopitys montana of South America, is the closest relative to P. taxifolia.^[12] A 2012 study based on rbcL data sequencing revealed that both species are nearly allied to species within the genus Pectinopitys (formerly placed within the same genus).^[16]

History

P. taxifolia was first described as Dacrydium taxifolium by the British botanist Aylmer Lambert in his work A Description of the Genus Pinus.^[17] It is the basionym (original scientific name) of the species.^[3] P. taxifolia was described as Dacrydium mai and Podocarpus spicatus in 1838. It was attempted to be renamed to Stachycarpus spicatus in 1891 by French botanist Philippe Édouard Léon Van Tieghem.^[18][19] American botanist David John de Laubenfels described it as Prumnopitys taxifolia in 1978,^[20] which is its currently recognised binomial name.^[18]

Etymology

The etymology (word origin) of P. taxifolia's genus, Prumnopitys, means 'plum-fruited pine', which derives from the Greek prunum, which means 'plum', and pitys which means 'fir' or 'pine'.^[21][22] The species name refers to the 'yew-like' leaves of the species, deriving from the Latin taxus, which is in reference to Taxus baccata.^[3][5] The species is commonly known as the mataī and or black pine.^[2] The word 'mataī' is likely a combination of the Māori language words 'mata', meaning 'unripe', and 'ī' meaning 'fermented' or 'sour'; likely referring to the bitter taste of resin exuded by the trunk.^[22] In 1907, New Zealand ethnographer Elsdon Best recorded that young trees are known in Māori as kāī, kākāī, and māī. The British missionary Richard Taylor, recorded that mature trees were also known as te mai.^[23]

Ecology

Feral pigs are capable of dispersing P. taxifolia's seeds.

Tūī have been recorded as dispersers of P. taxifolia's fruits.

P. taxifolia's seeds are dispersed by fruit-eating animals (frugivores)^[24] such as feral pigs (Sus scrofa). A 2012 study found that P. taxifolia seeds can still germinate after being excreted by feral pigs, with a success rate of 57 percent.^[25] A 2021 study hypothesised P. taxifolia's seeds were consumed by the extinct little bush moa (Anomalopteryx didiformis), although in low quantities when compared to other native species at the studied site at Borland Burn in Fiordland National Park.^[26] The seeds of P. taxifolia reflect some ultraviolet radiation, which is visible to some species of birds and vertebrates, although they do not reflect as strongly as Dacrycarpus dacrydioides.^[27] The seeds are eaten by the endemic moth, Heterocrossa iophaea.^[28] P. taxifolia is a host to the native insects, Ambeodontus tristis and Prionoplus reticularis.^[29]

A. E. Beveridge (1964) noted that sixty blackbirds (Turdus merula) were observed feeding on P. taxifolia seeds at Minginui.^[30] The kākā (Nestor meridionalis) have been recorded destroying the seeds of P. taxifolia. A 1989 study, published in the New Zealand Journal of Ecology, recorded the kererū (Hemiphaga novaeseelandiae), kōkako (Callaeas wilsoni), tūī (Prosthemadera novaeseelandiae), and weka (Gallirallus australis) as dispersers of the seeds of P. taxifolia.^[31] In 2023, a study published in MycoKeys, revealed three new Chaenothecopsis liverwort species that grow primarily on the exudates P. taxifolia. One of these species, C. matai, was named in honour of the tree.^[32] Like all conifers, the ovules of P. taxifolia are pollinated by the wind.^[33] The cones of P. taxifolia have an elongated central axis with about twelve ovules. Each ovule is positioned beneath arranged bracts (specialised leaves). At the base of each bract, there is a groove that forms a small gutter around the ovule. During pollination, pollen collects into the grooves before and after a drop of secretion appears, helping to capture pollen efficiently.^[34] P. taxifolia is sensitive to fire and has a moderate flammability rate.^[35] 

Distribution

P. taxifolia is endemic to New Zealand; its range primarily covers the North and South Islands. It also occurs on Stewart Island, but it is extremely uncommon there.^[2] In The Forest Flora of New Zealand, published in 1889, Thomas Kirk reported only one solitary specimen growing on the southern side of Halfmoon Bay. It commonly coincides with Nothofagus species in the South Island's West Coast Region.^[36] Kirk noted in his 1889 revision of New Zealand plants that the species was very common in the central areas of the North Island and in the western and south-western parts of the South Island.^[37]

The conservation status of P. taxifolia was assessed by the IUCN Red List in 2013 as "Least Concern", and its population trend was evaluated as "Stable".^[36] Its assessment in the New Zealand Threat Classification System was evaluated in 2023 as "Not Threatened".^[2]

Habitat

P. taxifolia is typically found in lowland and montane forests.^[2] It occurs from 20–1,000 m (70–3,000 ft) above sea level. It is commonly found on mountain slopes and grows in fertile, well-drained soils. In the eastern regions of both islands, where rainfall is relatively low, the tree can still grow well in drier climates. The largest specimens are typically found growing in deep pumice soils or in lime-rich soils beneath limestone escarpments.^[2][8] Similar to Pectinopitys ferruginea, the tree is commonly found on alluvial soils in the West Coast Region of the South Island.^[38] P. taxifolia is a slow-growing tree and is highly shade-tolerant, regenerating fully under closed canopy.^[10][24]

Uses

[...] this pine resembles the English Yew in the form of its leaf; the fruit is a black, or purple berry, about the size of a wild cherry; it is sweet and rather slimy, but of an agreeable flavour.

—Richard Taylor, 1848^[39]

Although P. taxifolia had some uses as a timber, it was historically considered inferior to the kauri (Agathis australis) and rimu (Dacrydium cupressinum).^[5] P. taxifolia's timber is noted for its strength and durability,^[5][40] and was historically used for building bridges, house building (especially flooring and weatherboards), and railway sleepers. It was also used, to a smaller degree, for furniture-making.^[2][10] Although known as black pine to early European settlers, an 1853 source mentions that the tree was also known as 'maiberry' to early settlers.^[22][23]

P. taxifolia's seeds are edible and are described as sweet and rather slimy in taste. Another important resource from the tree is the gum exuded from the trunk, which is also edible, and is described as sweet and bitter in taste. It was coined 'mataī beer' by Europeans, which is still brewed into an alcoholic beverage in certain regions of the country.^[2][22] The timber is highly valued by the Māori and had a variety of uses, including being used for building waka (canoes) and to make traditional instruments. In Māori mythology, the blood-red colour of the inner bark is said to be attributed to the blood of Tunaroa, a mythological god, who was killed by the cultural hero Māui.^[7]