Banksia
This article includes a improve this article by introducing more precise citations. (June 2023) ) |
Banksia Temporal range:
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Banksia serrata | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Order: | Proteales |
Family: | Proteaceae |
Subfamily: | Grevilleoideae |
Tribe: | Banksieae
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Genus: | Banksia L.f. |
Type species | |
Banksia serrata | |
Diversity | |
About 170 species | |
Distribution of Banksia within Australia | |
Synonyms[1] | |
Banksia is a
Heavy producers of
Description
Banksias grow as
The leaves of Banksia vary greatly between species. Sizes vary from the narrow, 1–1+1⁄2 centimetre long needle-like leaves of B. ericifolia (heath-leaved banksia), to the very large leaves of B. grandis (bull banksia), which may be up to 45 centimetres long. The leaves of most species have serrated edges, but a few, such as B. integrifolia, do not. Leaves are usually arranged along the branches in irregular spirals, but in some species they are crowded together in whorls. Many species have differing juvenile and adult leaves (e.g., Banksia integrifolia has large serrated juvenile leaves).
The flowers are arranged in flower spikes or capitate flower heads.[4] The character most commonly associated with Banksia is the flower spike, an elongated inflorescence consisting of a woody axis covered in tightly packed pairs of flowers attached at right angles. A single flower spike generally contains hundreds or even thousands of flowers; the most recorded is around 6000 on inflorescences of B. grandis. Not all Banksia have an elongate flower spike, however: the members of the small Isostylis complex have long been recognised as banksias in which the flower spike has been reduced to a head; and recently the large genus Dryandra has been found to have arisen from within the ranks of Banksia, and sunk into it as B. ser. Dryandra. They similarly have capitate flower heads rather than spikes.
Banksia flowers are usually a shade of
Occasionally, multiple flower spikes can form. This is most often seen in Banksia marginata and B. ericifolia[5][6] (pictured right).
As the flower spikes or heads age, the flower parts dry up and may turn shades of orange, tan or dark brown colour, before fading to grey over a period of years. In some species, old flower parts are lost, revealing the axis; in others, the old flower parts may persist for many years, giving the fruiting structure a hairy appearance. Old flower spikes are commonly referred to as "cones", although they are not technically cones according to the botanical definition of the term: cones only occur in conifers and cycads.
Despite the large number of flowers per inflorescence, only a few of them ever develop fruit, and in some species a flower spike will set no fruit at all. The fruit of Banksia is a woody follicle embedded in the axis of the inflorescence. In many species, the resulting structure is a massive woody structure commonly called a cone. Each follicle consists of two horizontal valves that tightly enclose the seeds. The follicle opens to release the seed by splitting along the suture. In some species, each valve splits too. In some species the follicles open as soon as the seed is mature, but in most species most follicles open only after stimulated to do so by bushfire. Each follicle usually contains one or two small seeds, each with a wedge-shaped papery wing that causes it to spin as it falls to the ground.
Taxonomy
Specimens of Banksia were first collected by
The genus Banksia was finally described and named by
The first specimens of a Dryandra were collected by
In 1891, Otto Kuntze, strictly applying the principle of priority, argued that Pimelea should revert to the name Banksia J.R.Forst & G.Forst. He proposed the new genus Sirmuellera to replaced Banksia L.f. and transferred its species to the new genus.[13] This arrangement was largely ignored by Kuntze's contemporaries.[14]Banksia L.f. was formally conserved and Sirmuellera rejected in 1940.[15]
Banksia belongs to the family
Subgeneric arrangement
Alex George arranged the genus into two subgenera—subgenus Isostylis (containing B. ilicifolia, B. oligantha and B. cuneata) and subgenus Banksia (containing all other species except those he considered dryandras)—in his 1981 monograph and 1999 treatment for the Flora of Australia series. He held that flower morphology was the key to relationships in the genus. Austin Mast and Kevin Thiele published the official merging of Dryandra within Banksia in 2007, recalibrating the genus into subgenus Banksia and subgenus Spathulatae.[17]
Distribution and habitat
All but one of the living Banksia species are
The vast majority of Banksia are found in sandy or gravelly soils, though some populations of B. marginata (silver banksia) and B. spinulosa do occur on soil that is heavier and more clay-like. B. seminuda is exceptional for its preference for rich loams along watercourses.
Most occur in
, with B. seminuda being one of the forest trees in suitable habitat.Most species do not grow well near the
Studies of the south-western species have found the distribution of Banksia species to be primarily constrained by rainfall. With the exception of B. rosserae, no species tolerates annual rainfall of less than 200 millimetres, despite many species surviving in areas that receive less than 400 millimetres. Banksia species are present throughout the region of suitable rainfall, with greatest speciation in cooler, wetter areas. Hotter, drier regions around the edges of its range tend to have fewer species with larger distributions. The greatest species richness occurs in association with uplands, especially the Stirling Range.[19]
Evolutionary history and fossil record
There are many fossils of Banksia. The oldest of these are fossil pollen between 65 and 59 million years old. There are fossil leaves between 59 and 56 million years old found in southern New South Wales.[20] The oldest fossil cones are between 47.8 and 41.2 million years old, found in Western Australia.[21] Although Banksia is now only native to Australia and New Guinea, there are fossils from New Zealand, between 21 and 25 million years old.[22]
Evolutionary scientists Marcell Cardillo and Renae Pratt have proposed a southwest Australian origin for banksias despite their closest relatives being north Queensland rainforest species.[23]
Ecology
Banksias are heavy producers of
A number of Banksia species are considered rare or endangered. These include B. brownii (feather-leaved banksia), B. cuneata (matchstick banksia), B. goodii (Good's banksia), B. oligantha (Wagin banksia), B. tricuspis (pine banksia), and B. verticillata (granite banksia).
Response to fire
Banksia plants are naturally adapted to the presence of regular bushfires in the Australian landscape. About half of Banksia species are killed by bushfire, but these regenerate quickly from seed, as fire also stimulates the opening of seed-bearing follicles and the germination of seed in the ground. The remaining species usually survive bushfire, either by resprouting from a woody base known as a lignotuber or, more rarely, epicormic buds protected by thick bark. In Western Australia, banksias of the first group are known as 'seeders' and the second group as 'sprouters'.[28]
Infrequent bushfires at expected intervals pose no threat, and are in fact beneficial for regeneration of banksia populations. However, too frequent bushfires can seriously reduce or even eliminate populations from certain areas, by killing seedlings and young plants before they reach fruiting age.[29] Many fires near urban areas are caused by arson, and thus the frequency is often much higher than fires would have been prior to human habitation. Furthermore, residents who live in areas near bushland may pressure local councils to burn areas near homes more frequently, to reduce fuel-load in the bush and thus reduce ferocity of future fires. Unfortunately there are often discrepancies in agreed frequency between these groups and conservation groups.
Dieback
Another threat to Banksia is the
Vulnerable plants typically die within a few years of infection. In
A number of species of Banksia are threatened by dieback. Nearly every known wild population of B. brownii shows some signs of dieback infection, which could possibly wipe it out within years.[32][33] Other vulnerable species include B. cuneata, and B. verticillata.
Dieback is notoriously difficult to treat, although there has been some success with
Because dieback thrives in moist soil conditions, it can be a severe problem for banksias that are watered, such as in the cut flower industry and urban gardens.
Uses
Gardening
Most of species are shrubs, only few of them can be found as trees and they are very popular because of their size, the tallest species are: B. integrifolia having its subspecies B. integrifolia subsp. monticola notable for reaching the biggest size for the genus and it is the most frost tolerant in this genus, B. seminuda, B. littoralis, B. serrata; species that can grow as small trees or big shrubs: B. grandis, B. prionotes, B. marginata, B. coccinea, B. speciosa and B. menziesii. Due to their size these species are popularly planted in parks, gardens and streets, the remaining species in this genus are only shrubs.
Banksias are popular garden plants in Australia because of their large, showy flower heads, and because the large amounts of
Over time, dwarf cultivars and prostrate species are becoming more popular as urban gardens grow ever smaller. These include miniature forms under 50 cm high of B. spinulosa and B. media, as well as prostrate species such as B. petiolaris and B. blechnifolia.
Banksias possibly require more maintenance than other Australian natives, though are fairly hardy if the right conditions are provided (sunny aspect and well drained sandy soil). They may need extra water during dry spells until established, which can take up to two years. If fertilised, only slow-release, low-
Within the Australian horticultural community there is an active subculture of Banksia enthusiasts who seek out interesting flower variants, breed and propagate cultivars, exchange materials and undertake research into cultivation problems and challenges. The main forum for exchange of information within this group is
Cut flower industry
With the exception of the
Woodworking
Banksia
. Woodturners throughout the world value Banksia pods for making ornamental objects.Indigenous uses
The Indigenous people of south-western Australia would suck on the flower spikes to obtain the nectar, they also soaked the flower spikes in water to make a sweet drink.[39][40][41] The Noongar people of southwest Western Australia also used infusions of the flower spikes to relieve coughs and sore throats.[41] The Girai wurrung peoples of the western district of Victoria used the spent flower cones to strain water by placing the cones in their mouths and using them like a straw.[42] Banksia trees are a reliable source of insect larvae which are extracted as food.
Cultural references
Field guides and other technical resources
A number of field guides and other semi-technical books on the genus have been published. These include:
- Field Guide to Banksias
- Written by Ivan Holliday and Geoffrey Watton and first published in 1975, this book contained descriptions and colour photographs of species known at the time. It was largely outdated by the publication of Alex George's classic 1981 monograph, but a revised and updated second edition was released in 1990.
- The Banksias
- This three volume monograph contains botanical illustrator Celia Rosser, with accompanying text by Alex George. Its publication represents the first time that such a large genus has been entirely painted. Published by Academic Press in association with Monash University, the three volumes were published in 1981, 1988 and 2000 respectively.
- The Banksia Book
- Begun by Australian photographer Fred Humphreys and Charles Gardner, both of whom died before its completion, The Banksia Book was eventually completed by Alex George and first published in 1984. It included every species known at the time, with a second edition appearing in 1987 and third in 1996.
- The Banksia Atlas
- In 1983 the Australian Biological Resources Study (ABRS) decided to pilot an Australia-wide distribution study of a significant plant genus. Banksia was chosen because it was a high-profile, widely distributed genus that was easily identified, but for which distribution and habitat was poorly known. The study mobilised over 400 volunteers, collecting over 25,000 field observations over a two-year period. Outcomes included the discovery of two new species, as well as new varieties and some rare colour variants, and discoveries of previously unknown populations of rare and threatened species. The collated data was used to create The Banksia Atlas, which was first published in 1988.[43]
- Banksias, Waratahs and Grevilleas and all other plants in the Australian Proteaceae family
- Written by J. W. Wrigley and M. Fagg, this was published by Collins Publishers in 1989. A comprehensive text on all the Proteaceae genera with good historical notes and an overview of the 1975 Johnson & Briggs classification. It is out of print and hard to find.
May Gibb's "Banksia men"
Perhaps the best known cultural reference to Banksia is the "big bad Banksia men" of May Gibbs' children's book Snugglepot and Cuddlepie. Gibb's "Banksia men" are modelled on the appearance of aged Banksia "cones", with follicles for eyes and other facial features. There is some contention over which species actually provided the inspiration for the "Banksia men": the drawings most resemble the old cones of B. aemula or B. serrata, but B. attenuata (slender banksia) has also been cited, as this was the species that Gibbs saw as a child in Western Australia.[44]
Other cultural references
In 1989, the Banksia Environmental Foundation was created to support and recognise people and organizations that make a positive contribution to the environment. The Foundation launched the annual Banksia Environmental Awards in the same year.[45]
Announced in June 2023, the exoplanet WASP-19b was named "Banksia" in the third NameExoWorlds competition. The approved name was proposed by a team from Brandon Park Primary School in Wheelers Hill (Melbourne, Australia), led by scientist Lance Kelly and teacher David Maierhofer,[46] after various types of Banksia plants.[47]
Selected species
- B. archaeocarpa†
- B. attenuata
- B. integrifolia
- B. seminuda
- B. ericifolia
- B. grandis
- B. marginata
- B. prionotes
- B. dentata
- B. novae-zelandiae†
- B. spinulosa
- B. sphaerocarpa
- B. sessilis
- B. nobilis
- B. dallanneyi
- B. praemorsa
- B. repens
- B. rosserae
- B. elderiana
- B. solandri
- B. oreophila
- B. brownii
- B. montana
- B. goodii (Good's Banksia)
- B. tricuspis (Pine Banksia)
- B. verticillata (Granite Banksia)
- Isostylis
- B. cuneata (Matchstick Banksia)
- B. ilicifolia (Holly-leaved Banksia)
- B. oligantha (Wagin Banksia)
See also
Notes
- ^ a b "Banksia L.f." Plants of the World Online. Royal Botanical Gardens, Kew. 2023. Retrieved 23 June 2023.
- ^ Banksias (Proteaceae) (PDF). Australian Plants Society NSW. 2021.
- ^ Liber C (2004). "Really Big Banksias". Banksia Study Group Newsletter. 6: 4–5.
- ^ George 1999, p. 175.
- ^ Johnson, S (1992). "Multiple Flower Heads". Banksia Study Report. 9: 58.
- ^ Blake, T (1988). "Multiple Heads". Banksia Study Report. 8: 2.
- ^ Cook, James (1893). William J. L. Wharton (ed.). . London: E. Stock.
- ^ Wrigley & Fagg 1991, p. 80.
- Carolus Linnaeus the Younger (1782). Supplementum Plantarum Systema Vegetabilium Editionis Decima Tertia, Generum Plantarum Editionis Fexta, Et Specierum Plantarum Editionis Secunda. Brunsvigae: Orphanotrophei.
- ^ Salkin, Abraham Isaac (Alf) (1981). "A Short History of the Discovery and Naming of Banksias in Eastern Australia: Part I, Banks & Solander". Victorian Naturalist. 98 (2).
- ISBN 978-1-876473-54-9.
- ^ Wrigley & Fagg 1991, pp. 151–152.
- ^ Kuntze, Otto (1891). Revisio generum plantarum. Vol. 2. Leipzig: Arthur Felix. pp. 581–582.
- JSTOR 4107078.
- JSTOR 4111642.
- PMID 19116275.
- ISSN 1030-1887.
- ^ Sleumer, H (1955). "Proteaceae". Flora Malesiana. 5 (1): 147–206 – via Naturalis Institutional Repository.
- JSTOR 2845847.
- .
- .
- PMID 21622389.
- PMID 23957450.
- doi:10.1071/BT00004.
- doi:10.1071/BT00084.
- doi:10.1071/BT01075.
- S2CID 189826442.
- .
- doi:10.1071/BT01078.
- .
- ^ "Impacts in WA". Managing Dieback. Department of Environment and Conservation (Western Australia). Archived from the original on 3 September 2007. Retrieved 21 February 2007.
- ^ Banksia brownii, Species Profile and Threats Database, Department of the Environment and Heritage, Australia.
- OCLC 183084186.[page needed]
- ^ "Phytophthora in forests and natural ecosystems". Second International IUFRO meeting. Murdoch University. Archived from the original on 20 July 2006. Retrieved 26 June 2006.
- ^ Collins, Collins & George 2008, p. 83.
- ^ Collins, Collins & George 2008, p. 53.
- ^ Collins, Collins & George 2008, p. 57.
- ^ Salkin, Abraham Isaac (1979). Variation In Banksia in Eastern Australia: An Investigation Using Experimental Methods. Clayton, Victoria: Monash University. p. 239.
- OCLC 35655910.[page needed]
- ^ J. H. Maiden (1889). The useful native plants of Australia : Including Tasmania. Turner and Henderson, Sydney.
- ^ Wikidata Q113330855.
- ^ Dawson, 1881. Australian Aborigines – the language and customs of several tribes of Aborigines in the Western district of Victoria. Page 22.
- ISBN 0-644-07124-9.
- ^ Collins, Collins & George 2008, p. 68.
- ^ "Introduction and History". Banksia Environmental Foundation. Archived from the original on 24 August 2006. Retrieved 11 July 2006.
- better source needed]
- ^ 2022 Approved Names". nameexoworlds.iau.org. IAU. Retrieved 7 June 2023
References
- Boland, D. J.; et al. (1984). Forest Trees of Australia (Fourth edition revised and enlarged). CSIRO Publishing, Collingwood, Victoria, Australia. OCLC 30628509..
- Collins, Kevin; Collins, Kathy; ISBN 978-1-876473-68-6.
- S2CID 196677407.
- ISBN 978-0-864-17143-6.
- ISBN 978-0-643-06454-6.
- Harden, Gwen (2002). "Banksia". In Harden, Gwen (ed.). Flora of New South Wales: Volume 2 (Revised ed.). New South Wales University Press, Kensington. pp. 82–86. ISBN 978-0-86840-156-0.
- Taylor, Anne; ISBN 0-644-07124-9.
- Thiele, K; Ladiges, PY (1996). "A cladistic analysis of Banksia (Proteaceae)". Australian Systematic Botany. 9 (5): 661–733. .
- Wrigley, John; Fagg, Murray (1991). Banksias, Waratahs and Grevilleas. Sydney, New South Wales: Angus & Robertson. ISBN 978-0-207-17277-9.
External links
- "Banksia". Flora of Australia Online. Department of the Environment and Heritage, Australian Government.
- "Banksia L.f." Department of Biodiversity, Conservation and Attractions.
- The Banksia Page of ASGAP
- Banksia Study Group of ASGAP
- Banksia Farm, Private collection of all Banksia Species, Mount Barker, Western Australia