Langbahn Team – Weltmeisterschaft

Beilschmiedia tawa

Tawa
A tawa tree near Tangoio, New Zealand
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Magnoliids
Order: Laurales
Family: Lauraceae
Genus: Beilschmiedia
Species:
B. tawa
Binomial name
Beilschmiedia tawa
Synonyms
  • Beilschmiedia tawaroa

Beilschmiedia tawa, commonly known as the tawa, is a New Zealand broadleaf tree common in the central parts of the country. Tawa is often the dominant canopy tree species in lowland forests in the North Island and the north east of the South Island, but will also often form the subcanopy in primary forests throughout the country in these areas, beneath podocarps such as kahikatea, matai, miro and rimu. Individual specimens may grow up to 30 metres or more in height with trunks up to 1.2 metres in diameter, and they have smooth dark bark. The Māori word "tawa" is the name for the tree.

Tawa produce small inconspicuous flowers followed by 2–3.5 cm long fruit of a dark red plum colour. With such large fruits, tawa is notable for the fact that it relies solely on the New Zealand pigeon (kererū) and (where present) the North Island kōkako for dispersal of its seed. These are the only remaining birds from New Zealand's original biota large enough to eat the fruits of this tree and pass the seeds through their guts and excrete them unharmed. Tawa can also support significant epiphyte gardens in their canopies, which are one of the few habitats known to be frequented by the enigmatic, arboreal striped skink.

This tree gives its name to a northern suburb of Wellington, Tawa.

Description

Leafage of Beilschmiedia tawa

Beilschmiedia tawa, or tawa, is a medium sized evergreen tree in the family Lauraceae endemic to New Zealand. It grows to a height of up to 25–35 m (82–115 ft) tall and has a trunk of up to 1 m (3 ft 3 in) in diameter.[2]

Flowering occurs in (October–) January (–May), producing an inflorescence (flower spike) up to 100 mm (3.9 in) long. Its flowers are 2–4 mm (0.079–0.157 in) in diamater and palish green in colour. Fruiting occurs in (December–) January (–March), the fruit B. tawa produces is an oval shaped drupe of up to (20–)30(–38) x (9–)12(–18) mm long, 1-seeded, its pericarp is fleshy, dark purple in colour when ripe, and is usually glaucous or shiny.[3]

B. tawa has slender to moderately robust erecting branches. Its leaves are (30–)40–80(–95) x (8–)11–16(–40) mm long, yellowish and green in colour, smooth when mature with its undersides glaucous. Its petioles are (6–)8(–12) mm long.[3]

Distribution

B. tawa is a tree endemic to New Zealand. It is most commonly found in the North Island, and on many of its off-shore islands. In the South Island, the tree is less common with its population being mainly centred in the Marlborough Region, with its southernmost population located in the Kaikōura Ranges, in the northern Canterbury Region.[4]

B. tawa is only naturally absent in the highest regions of the Central Volcanic Plateau, the montane forests, and locally unfavourable locations in the lowland woods of the North Island. Additionally, secondary forests caused by fire are unusual for it. The Aupōuri Peninsula's sand-dune terrain and the beaches of Kaipara and Manawatū are the only places in the country where there are gaps due to the lack of native forest lowland distribution. Between the Mōkau and Whanganui Rivers and in the hilly terrain of the eastern Bay of Plenty hinterland hold the largest populations of B. tawa.[4]

In the South Island, B. tawa is largely present in the seawards valleys near of the Marlborough Region, but is it uncommon inland. Its most westerly known occurrence in the South Island is in the Tākaka Valley, north-west of the Nelson Region. The Kaikōura Ranges in the Canterbury region are the southernmost geographical location where B. tawa naturally occur.[5]

Uses

The wood of this tree can be used for attractive and resilient floorboarding. Although largely protected in conservation areas and by robust environmental legislation, licences are occasionally granted for the odd fallen tree to be milled for its timber.

The kernel of the tawa berry was used by Māori as food.[6] The berries were steamed in a hāngī (earth oven) for two days, then washed to remove the turpentine-flavoured pulp. The dried kernels were stored. When required, they were soaked in hot water and pounded, sometimes flavouring being added to the mashed meal.

See also

References

Citations

  1. ^ de Kok, R. 2022. Beilschmiedia tawa. The IUCN Red List of Threatened Species 2022: e.T62020024A62020027. https://dx.doi.org/10.2305/IUCN.UK.2022-1.RLTS.T62020024A62020027.en. Accessed on 13 April 2023.
  2. ^ Knowles & Beveridge 1982, p. 1.
  3. ^ a b De Lange 2024.
  4. ^ a b Knowles & Beveridge 1982, pp. 6, 8–9.
  5. ^ Wardle 1971, p. 18.
  6. ^ McLintock, A.H. (1966). 'PLANTS, EDIBLE NATIVE', from An Encyclopaedia of New Zealand. Retrieved 16 October 2018.

Works cited

Journals

Books

Websites