Banksia tricuspis

Banksia tricuspis, commonly known as Lesueur banksia or pine banksia, is a plant in the family Proteaceae and is endemic to a small area in the south-west of Western Australia. It is a stunted tree or shrub with narrow leaves and cylindrical spikes of golden-coloured flowers and it occurs in a geographic range of just 15 square kilometres near Jurien.

Lesueur banksia
B. tricuspis
roadside planting in Wanneroo

Priority Four — Rare Taxa (DEC)
Scientific classification
Kingdom:
Plantae
(unranked):
Angiosperms
(unranked):
Eudicots
Order:
Proteales
Family:
Proteaceae
Genus:
Banksia
Subgenus:
Banksia subg. Banksia
Section:
Banksia sect. Oncostylis
Series:
Banksia ser. Tricuspidae

Species:
B. tricuspis
Binomial name
Banksia tricuspis

Description

Banksia tricuspis is a shrub or small tree, often with an irregular shape, which grows to a height of 4 m (10 ft) with thick, grey, wrinkled, fire-resistant bark on its trunk. New growth is produced in spring and is pale greenish-brown. The leaves are mostly crowded near the ends of the branches, linear in shape, 50–130 mm (2–5 in) long 1.0–1.5 mm (0.04–0.06 in) wide with the edges rolled under and end in three pointed teeth. The upper surface of the leaves is covered with soft hairs at first but becomes glabrous as the leaves mature. The lower surface is woolly.[2]

As with many other members of the genus, inflorescences or flower spikes may contain hundreds or thousands of individual flowers, each of which consists of a tube-shaped perianth made up of four joined tepals, and one long wiry style. In this species the spike is on the end of a branch and is 70–150 mm (3–6 in) long and 70–90 mm (3–4 in) wide when the flowers open. Each perianth is golden-yellow, 23–26 mm (0.9–1 in) long, hairy on the outside but glabrous inside. Flowering occurs from late March to July. Only up to 35 of the flowers on a spike will form seeds and these are contained in large, woody fruit called follicles. In B. tricuspis, these protrude from the spike and are elliptic in shape, 8–16 mm (0.3–0.6 in) high and 15–28 mm (0.6–1 in) wide, glabrous and slightly rough. The fruit remain closed until the plant is heated during a fire, after which one or two winged seeds are released from each follicle.[2]

B. tricuspis habit in Lesueur National Park
B. tricuspis leaves
B. tricuspis young inflorescence

Taxonomy and naming

Banksia tricuspis was first formally described by Carl Meissner in 1855 from specimens collected by James Drummond and the description was published in Hooker's Journal of Botany and Kew Garden Miscellany.[3][4] The specific epithet (tricuspis) is a Latin word meaning "having three points",[5] referring to the three teeth on the leaf tips.[2]

This species is placed alone in series Banksia ser. Tricuspidae.[6]

Distribution and habitat

This banksia only occurs around Mount Lesueur in Lesueur National Park in the Geraldton Sandplains biogeographic region.[7][8] It grows in rocky lateritic soil in shrubland.[2]

Ecology

This plant is fire tolerant and new growth sprouts from epicormic buds after fire. There is evidence that black cockatoos (genus Calyptorhynchus) increase the rate of seed set by selectively destroying borers.[9]

Conservation

Banksia tricuspis is classified as "Priority Four" by the Government of Western Australia Department of Parks and Wildlife,[7] meaning that is rare or near threatened.[10] It is only known from an area of 15 km2 (6 sq mi).[11]

Use in horticulture

This is a slow-growing plant and may take 10 years to flower for the first time. The foliage is sparse except for at the branch tips and the flower spikes and old fruit are attractive. It grows best in sandy or rocky soil in a sunny location.[2] Seeds do not require any treatment, and take 18 to 57 days to germinate.[12]

References
  1. "Banksia tricuspis". Australian Plant Census. Retrieved 28 October 2019.
  2. George, Alex S. (1987). The Banksia Book (Second Edition). Kenthurst, New South Wales: Kangaroo Press (in association with the Society for Growing Australian Plants). ISBN 0-86417-006-8.
  3. "Banksia tricuspis". APNI. Retrieved 28 October 2019.
  4. Meissner, Carl (1855). "New Proteaceae of Australia". Hooker's Journal of Botany and Kew Garden Miscellany. 7: 118. Retrieved 31 May 2016.
  5. Lewis, Charlton T.; Short, Charles. "creber". A Latin Dictionary. Retrieved 30 May 2016.
  6. Liber, Cas (2004). "Banksia tricuspis – evidence for placement in Abietinae (?)" (PDF). Banksia Study Group Newsletter. 6 (1). Retrieved 31 May 2016.
  7. "Banksia tricuspis". FloraBase. Western Australian Government Department of Parks and Wildlife.
  8. Paczkowska, Grazyna; Chapman, Alex R. (2000). The Western Australian flora : a descriptive catalogue. Perth: Wildflower Society of Western Australia. p. 468. ISBN 0646402439.
  9. Lamont, Byron B.; Enright, Neal J.; Witkowski, E. T. F.; Groeneveld, J. (2007). "Conservation biology of banksias: insights from natural history to simulation modelling". Australian Journal of Botany. 55 (3): 280–292. doi:10.1071/BT06024.
  10. "Conservation codes for Western Australian Flora and Fauna" (PDF). Government of Western Australia Department of Parks and Wildlife. Archived from the original (PDF) on 5 April 2018. Retrieved 31 May 2016.
  11. Taylor, Anne; Hopper, Stephen (1988). The Banksia Atlas (Australian Flora and Fauna Series Number 8). Canberra: Australian Government Publishing Service. ISBN 0-644-07124-9.
  12. Sweedman, Luke; Merritt, David (2006). Australian seeds: a guide to their collection, identification and biology. CSIRO Publishing. p. 203. ISBN 0-643-09298-6.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.