Banksia petiolaris
Encyclopedia
Banksia petiolaris is a species of shrub
of the genus Banksia
in the Proteaceae
family. It is a prostrate banksia, a group of several closely related species all with horizontal stems and thick, leathery upright leaves. No varieties have been subsequently described. It bears yellow inflorescences in spring. It is found in sandy soils in the south coastal regions of Western Australia in the vicinity of Esperance
. It is nonlignotuberous, regenerating by seed after bushfire. Banksia petiolaris adapts readily to cultivation, and is suitable for rockeries and as a groundcover.
s are yellow in overall colour and range from 9 to 16 cm (3.6–6.2 in) high. As the flower spikes age, they fade to a greyish colour, the old flowers persisting. Up to 20 follicles may appear on each spike. Covered with a fine grey fur, they are elliptical in shape and measure 2.8–3.8 cm (1.1–1.7 in) in length, and 1.5–2 cm (0.6–0.8 in) in width.
It is nonlignotuberous, regenerating by seed after bushfire.
in 1864, its specific name Latin
for "with petioles". The type specimen was most likely collected in 1861 by G. Maxwell between Cape Le Grand
and Cape Arid
and is housed in Melbourne. No further subspecies or varieties of B. petiolaris have been described, and it has no taxonomic synonyms. Its only nomenclatural synonym is Sirmuellera petiolaris (F.Muell.) Kuntze, which arose from Otto Kuntze
's unsuccessful 1891 attempt to transfer Banksia into the new name Sirmuellera.
It is one of six closely related species in section Banksia ser. Prostratae
, all endemic to Western Australia
, and all with a prostrate habit. George holds it as closely related to B. blechnifolia.
In 1996, botanists Kevin Thiele
and Pauline Ladiges published an arrangement informed by a cladistic
analysis of morphological
characteristics. Their arrangement
maintained B. petiolaris in B. subg. Banksia and series Prostratae. They found it to be basal (the earliest offshoot) to the other prostrate banksias. Questioning the emphasis on cladistics in Thiele and Ladiges' arrangement, George published a slightly modified version of his 1981 arrangement in his 1999 treatment of Banksia for the Flora of Australia
series of monographs. To date, this remains the most recent comprehensive arrangement. The placement of B. petiolaris in George's 1999 arrangement
may be summarised as follows:
Since 1998, American botanist Austin Mast
has been publishing results of ongoing cladistic analyses of DNA sequence
data for the subtribe Banksiinae, which includes Banksia. With respect to B. petiolaris, Mast's results have some semblance to George and Thiele's. It is somewhat basal in a group with the other prostrate species as well as species in series Tetragonae, and B. elderiana
, B. baueri
, and B. lullfitzii
. However, B. repens, B. chamaephyton and B. blechnifolia form a closely knit group within this group, and the overall inferred phylogeny is very different from George's arrangement. Early in 2007, Mast and Thiele initiated a rearrangement of Banksiinae by publishing several new names, including subgenus Spathulatae
for the species of Banksia that have spoon-shaped cotyledon
s; in this way they also redefined the autonym
B. subgenus Banksia
. They have not yet published a full arrangement, but if their nomenclatural changes are taken as an interim arrangement, then B. petiolaris is placed in subgenus Banksia.
east to Israelite Bay, concentrated in two disjunct ranges – an eastern one around Cape Arid National Park
, and western one east of Scaddan. It is found in white sandy soils in heathland (kwongan
) or mallee-heath, but sometimes occurs with the taller Banksia speciosa
.
survey.
An assessment of the potential impact of climate change
on this species found that its range is likely to contract by between 30% and 80% by 2080, depending on the severity of the change.
Banksia petiolaris has the longest-lived angiosperm leaves so far recorded – a study published in 1992 recorded a lifespan of up to 13 years for a single leaf, while leaves of 10 years of age ably maintained their ability to photosynthesize compared with young leaves. The authors concluded that leaf longevity is advantageous in plants in nutrient poor soils, as the loss of valuable nutrients in leaf loss is minimised (the leaves store much of a plants' nutrients).
, it does require a well drained soil, preferably fairly sandy. Like other banksias, it grows best in full sun. It makes an attractive prostrate groundcover, and can be used in embankments and to reduce soil erosion, as well as rockeries. It is tolerant of alkaline soils, with one cultivated specimen recorded tolerating a pH of 9.5. Seeds do not require any treatment, and takes about 18 to 49 days to germinate.
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
of the genus Banksia
Banksia
Banksia is a genus of around 170 species in the plant family Proteaceae. These Australian wildflowers and popular garden plants are easily recognised by their characteristic flower spikes and fruiting "cones" and heads. When it comes to size, banksias range from prostrate woody shrubs to trees up...
in the Proteaceae
Proteaceae
Proteaceae is a family of flowering plants distributed in the Southern Hemisphere. The family comprises about 80 genera with about 1600 species. Together with the Platanaceae and Nelumbonaceae they make up the order Proteales. Well known genera include Protea, Banksia, Embothrium, Grevillea,...
family. It is a prostrate banksia, a group of several closely related species all with horizontal stems and thick, leathery upright leaves. No varieties have been subsequently described. It bears yellow inflorescences in spring. It is found in sandy soils in the south coastal regions of Western Australia in the vicinity of Esperance
Esperance, Western Australia
Esperance is a large town in the Goldfields-Esperance region of Western Australia, located on the Southern Ocean coastline approximately east-southeast of the state capital, Perth. The shire of Esperance is home to 9,536 people as of the 2006 census, its major industries are tourism, agriculture,...
. It is nonlignotuberous, regenerating by seed after bushfire. Banksia petiolaris adapts readily to cultivation, and is suitable for rockeries and as a groundcover.
Description
Banksia petiolaris is a prostrate shrub which can spread to a diameter of 2 metres (7 ft), its thick stems grow horizontally on the ground and are covered in fine hair. The new growth is more densely covered with velvety orange brown hair. The large leathery upright leaves arise vertically on petioles up to 15 cm (6 in) high. The adaxial surface faces north and is inclined at around 15 degrees off vertical. The leaf laminae can reach 60 cm (24 in) in length and 4 cm (1.6 in) wide. They are dull green with serrated margins and a white undersurface. Dead leaves remain on the plant. Flowering occurs in late spring. The cylindrical inflorescenceInflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
s are yellow in overall colour and range from 9 to 16 cm (3.6–6.2 in) high. As the flower spikes age, they fade to a greyish colour, the old flowers persisting. Up to 20 follicles may appear on each spike. Covered with a fine grey fur, they are elliptical in shape and measure 2.8–3.8 cm (1.1–1.7 in) in length, and 1.5–2 cm (0.6–0.8 in) in width.
It is nonlignotuberous, regenerating by seed after bushfire.
Taxonomy
Banksia petiolaris was first described by Victorian state botanist Ferdinand von MuellerFerdinand von Mueller
Baron Sir Ferdinand Jacob Heinrich von Mueller, KCMG was a German-Australian physician, geographer, and most notably, a botanist.-Early life:...
in 1864, its specific name Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
for "with petioles". The type specimen was most likely collected in 1861 by G. Maxwell between Cape Le Grand
Cape Le Grand National Park
Cape Le Grand National Park is a national park in Western Australia, south-east of Perth and east of Esperance. The park covers an area of The area is an ancient landscape has above sea level for well over 200 million years and remained unglaciated...
and Cape Arid
Cape Arid National Park
Cape Arid National Park is a national park in Western Australia , south east of Perth. The park is situated east of Esperance and lies on shore from the eastern end of the Recherche Archipelago...
and is housed in Melbourne. No further subspecies or varieties of B. petiolaris have been described, and it has no taxonomic synonyms. Its only nomenclatural synonym is Sirmuellera petiolaris (F.Muell.) Kuntze, which arose from Otto Kuntze
Otto Kuntze
Otto Carl Ernst Kuntze was a German botanist.-Biography:Otto Kuntze was born in Leipzig.An apothecary in his early career, he published an essay entitled Pocket Fauna of Leipzig. Between 1863 and...
's unsuccessful 1891 attempt to transfer Banksia into the new name Sirmuellera.
It is one of six closely related species in section Banksia ser. Prostratae
Banksia ser. Prostratae
Banksia ser. Prostratae is a taxonomic series in the genus Banksia. It consists of six closely related species in section Banksia, all endemic to Western Australia, with a prostrate habit.Banksia ser...
, all endemic to Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...
, and all with a prostrate habit. George holds it as closely related to B. blechnifolia.
In 1996, botanists Kevin Thiele
Kevin Thiele
Kevin R. Thiele is curator of the Western Australian Herbarium. His research interests include the systematics of the plant families Proteaceae, Rhamnaceae and Violaceae, and the conservation ecology of grassy woodland ecosystems...
and Pauline Ladiges published an arrangement informed by a cladistic
Cladistics
Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...
analysis of morphological
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
characteristics. Their arrangement
Thiele and Ladiges' taxonomic arrangement of Banksia
Kevin Thiele and Pauline Ladiges' taxonomic arrangement of Banksia, published in 1996, was a novel taxonomic arrangement that was intended to align the taxonomy of Banksia more closely with the phylogeny that they had inferred from their cladistic analysis of the genus...
maintained B. petiolaris in B. subg. Banksia and series Prostratae. They found it to be basal (the earliest offshoot) to the other prostrate banksias. Questioning the emphasis on cladistics in Thiele and Ladiges' arrangement, George published a slightly modified version of his 1981 arrangement in his 1999 treatment of Banksia for the Flora of Australia
Flora of Australia (series)
The Flora of Australia is a 59 volume series describing the vascular plants, bryophytes and lichens present in Australia and its external territories...
series of monographs. To date, this remains the most recent comprehensive arrangement. The placement of B. petiolaris in George's 1999 arrangement
George's taxonomic arrangement of Banksia
Alex George's taxonomic arrangement of Banksia was the first modern-day arrangement for that genus. First published in 1981 in the classic monograph The genus Banksia L.f. , it superseded the arrangement of George Bentham, which had stood for over a hundred years. It was overturned in 1996 by Kevin...
may be summarised as follows:
- BanksiaBanksiaBanksia is a genus of around 170 species in the plant family Proteaceae. These Australian wildflowers and popular garden plants are easily recognised by their characteristic flower spikes and fruiting "cones" and heads. When it comes to size, banksias range from prostrate woody shrubs to trees up...
- B. subg. BanksiaBanksia subg. BanksiaBanksia subg. Banksia is a valid botanic name for a subgenus of Banksia. As an autonym, it necessarily contains the type species of Banksia, B. serrata . Within this constraint, however, there have been various circumscriptions.-Banksia verae:B. subg...
- B. sect. BanksiaBanksia sect. BanksiaBanksia sect. Banksia is one of four sections of Banksia subgenus Banksia. It contains those species of subgenus Banksia with straight or sometimes curved but not hooked styles. These species all have cylindrical inflorescences and usually exhibit a bottom-up sequence of flower anthesis...
- B. ser. SalicinaeBanksia ser. SalicinaeBanksia ser. Salicinae is a valid botanic name for a series of Banksia. First published by Carl Meissner in 1856, the name has had three circumscriptions.-According to Meissner:...
(11 species, 7 subspecies) - B. ser. GrandesBanksia ser. GrandesBanksia ser. Grandes is a taxonomic series in the genus Banksia. It consists of two closely related species in section Banksia, both endemic to Western Australia. These are B. grandis and B. solandri ....
(2 species) - B. ser. BanksiaBanksia ser. BanksiaBanksia ser. Banksia is avalid botanic name for a series of Banksia. As an autonym, it necessarily contains the type species of Banksia, B. serrata . Within this constraint, however, there have been various circumscriptions.-According to Bentham:Banksia ser. Banksia originated in 1870 as...
(8 species) - B. ser. CrocinaeBanksia ser. CrocinaeBanksia ser. Crocinae is a taxonomic series in the genus Banksia. It consists of four closely related species, all of which are endemic to Western Australia; namely B. prionotes , B. burdettii , B. hookeriana and B. victoriae...
- B. ser. ProstrataeBanksia ser. ProstrataeBanksia ser. Prostratae is a taxonomic series in the genus Banksia. It consists of six closely related species in section Banksia, all endemic to Western Australia, with a prostrate habit.Banksia ser...
(6 species, 3 varieties)- B. goodiiBanksia goodiiBanksia goodii, commonly known as Good's Banksia, is an endangered shrub of Southwest Western Australia.Good's Banksia grows as a low shrub, either prostrate or with stems up to twenty centimetres high. The leaves are dark green with a prominent yellow midrib, and are held erect. They may be up...
- B. gardneriBanksia gardneriThe Prostrate Banksia is a species of prostrate shrub in the plant genus Banksia. It occurs along the south coast of Western Australia.-Scientific name:...
- B. gardneri var. gardneriBanksia gardneri var. gardneriBanksia gardneri var. gardneri is a variety of Banksia gardneri. As an autonym, it is defined as encompassing the type material of the species. It is native to the Southwest Botanical Province of Western Australia....
- B. gardneri var. brevidentataBanksia gardneri var. brevidentataBanksia gardneri var. brevidentata is a variety of Banksia gardneri. It is native to the Southwest Botanical Province of Western Australia....
- B. gardneri var. hiemalisBanksia gardneri var. hiemalisBanksia gardneri var. hiemalis is a variety of Banksia gardneri. It is native to the Southwest Botanical Province of Western Australia. Seeds do not require any treatment, and take around 19 days to germinate....
- B. gardneri var. gardneri
- B. chamaephytonBanksia chamaephytonThe Fishbone Banksia is a species of prostrate shrub in the plant genus Banksia. It occurs in sandplain country amongst low heath north of Perth, Western Australia.....
- B. repensBanksia repensBanksia repens, the Creeping Banksia, is a species of shrub in the plant genus Banksia. It occurs on the south coast of Western Australia from D'Entrecasteaux National Park in the west to Mount Ragged in the east....
- B. blechnifoliaBanksia blechnifoliaBanksia blechnifolia is a species of prostrate shrub in the plant genus Banksia. Found in sandy soils in the south coastal region of Western Australia in the vicinity of Lake King, it is non-lignotuberous, regenerating by seed after bushfire...
- B. petiolaris
- B. goodii
- B. ser. CyrtostylisBanksia ser. CyrtostylisBanksia ser. Cyrtostylis is a valid botanic name for a taxonomic series within the plant genus Banksia. First published at sectional rank by George Bentham in 1870, it was demoted to a series by Alex George in 1981. The name has had three circumscriptions.-According to Bentham:Bentham published B....
(13 species) - B. ser. TetragonaeBanksia ser. TetragonaeBanksia ser. Tetragonae is a taxonomic series in the genus Banksia. It consists of three closely related species of erect shrub with pendulous inflorescences in section Banksia. These are B. lemanniana , B. caleyi and B. aculeata ....
(3 species) - B. ser. Bauerinae (1 species)
- B. ser. QuercinaeBanksia ser. QuercinaeBanksia ser. Quercinae is avalid botanic name for a series of Banksia. First published by Carl Meissner in 1856, the name has had three circumscriptions.-According to Meissner:...
(2 species)
- B. ser. Salicinae
- B. sect. Coccinea (1 species)
- B. sect. OncostylisBanksia sect. OncostylisBanksia sect. Oncostylis is one of four sections of subgenus Banksia subg. Banksia. It contains those Banksia species with hooked pistils. All of the species in Oncostylis also exhibit a top-down sequence of flower anthesis, except for Banksia nutans which is bottom-up.Banksia sect...
(4 series, 22 species, 4 subspecies, 11 varieties)
- B. sect. Banksia
- B. subg. IsostylisBanksia subg. IsostylisBanksia subg. Isostylis is a subgenus of Banksia. It contains three closely related species, all of which occur only in Southwest Western Australia. Members of subgenus Isostylis have dome-shaped flower heads that are superficially similar to those of B. ser...
(3 species)
- B. subg. Banksia
Since 1998, American botanist Austin Mast
Austin Mast
Austin R. Mast is a research botanist. Born in 1972, he obtained a Ph.D. from the University of Wisconsin–Madison in 2000. He is currently an associate professor within the Department of Biological Science at Florida State University , and has been director of FSU's since August 2003.One of his...
has been publishing results of ongoing cladistic analyses of DNA sequence
DNA sequence
The sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...
data for the subtribe Banksiinae, which includes Banksia. With respect to B. petiolaris, Mast's results have some semblance to George and Thiele's. It is somewhat basal in a group with the other prostrate species as well as species in series Tetragonae, and B. elderiana
Banksia elderiana
The Swordfish Banksia , commonly known as the swordfish banksia or palm banksia, is a species of shrub in the plant genus Banksia. It occurs in two disjunct areas in the Goldfields-Esperance region of Western Australia...
, B. baueri
Banksia baueri
The Woolly Banksia is a species of shrub in the plant genus Banksia. It occurs in southwest Western Australia north and east of Albany. It has a distinctively large and hairy looking inflorescence which can be 300 mm or more long and up to 200 mm in diameter.It is placed alone in series...
, and B. lullfitzii
Banksia lullfitzii
Banksia lullfitzii is a species of shrub in the plant genus Banksia. A many-branched, spreading bush with golden-orange flowers, it occurs in scattered populations over a large area of the eastern goldfields of Western Australia...
. However, B. repens, B. chamaephyton and B. blechnifolia form a closely knit group within this group, and the overall inferred phylogeny is very different from George's arrangement. Early in 2007, Mast and Thiele initiated a rearrangement of Banksiinae by publishing several new names, including subgenus Spathulatae
Banksia subg. Spathulatae
Banksia subg. Spathulatae is a valid botanic name for a subgenus of Banksia. It was published in 2007 by Austin Mast and Kevin Thiele, and defined as containing all those Banksia species having spathulate cotyledons...
for the species of Banksia that have spoon-shaped cotyledon
Cotyledon
A cotyledon , is a significant part of the embryo within the seed of a plant. Upon germination, the cotyledon may become the embryonic first leaves of a seedling. The number of cotyledons present is one characteristic used by botanists to classify the flowering plants...
s; in this way they also redefined the autonym
Autonym (botany)
In botanical nomenclature, autonyms are automatically created names, as regulated by the International Code of Botanical Nomenclature . Autonyms are cited without an author. Relevant provisions are in articles 6.8, 22.1-3 and 26.1-3....
B. subgenus Banksia
Banksia subg. Banksia
Banksia subg. Banksia is a valid botanic name for a subgenus of Banksia. As an autonym, it necessarily contains the type species of Banksia, B. serrata . Within this constraint, however, there have been various circumscriptions.-Banksia verae:B. subg...
. They have not yet published a full arrangement, but if their nomenclatural changes are taken as an interim arrangement, then B. petiolaris is placed in subgenus Banksia.
Distribution and habitat
Endemic to Western Australia, Banksia petiolaris is found near the state's south coast from the vicinity of MunglinupMunglinup, Western Australia
Munglinup is a small town located in the Goldfields-Esperance region of Western Australia.The town is located along the South Coast Highway between Ravensthorpe and Esperance and close to the Munglinup River....
east to Israelite Bay, concentrated in two disjunct ranges – an eastern one around Cape Arid National Park
Cape Arid National Park
Cape Arid National Park is a national park in Western Australia , south east of Perth. The park is situated east of Esperance and lies on shore from the eastern end of the Recherche Archipelago...
, and western one east of Scaddan. It is found in white sandy soils in heathland (kwongan
Kwongan
Kwongan is a type of heathland found on the coastal plains of Western Australia. The name is derived from the language of the Noongar people. Kwongan comprises floristically-rich heath with dense thickets of sclerophyllous shrubs and isolated small trees...
) or mallee-heath, but sometimes occurs with the taller Banksia speciosa
Banksia speciosa
The Showy Banksia is a species of large shrub or small tree in the plant genus Banksia. It reaches up to 8 m in height...
.
Ecology
Like other banksias, B. petiolaris plays host to a variety of pollinators – insects such as bees, wasps and ants were all recorded in the 1988 The Banksia AtlasThe Banksia Atlas
The Banksia Atlas is an atlas that documents the ranges, habitats and growth forms of various species and other subgeneric taxa of Banksia, an iconic Australian wildflower genus...
survey.
An assessment of the potential impact of climate change
Climate change
Climate change is a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions or the distribution of events around that average...
on this species found that its range is likely to contract by between 30% and 80% by 2080, depending on the severity of the change.
Banksia petiolaris has the longest-lived angiosperm leaves so far recorded – a study published in 1992 recorded a lifespan of up to 13 years for a single leaf, while leaves of 10 years of age ably maintained their ability to photosynthesize compared with young leaves. The authors concluded that leaf longevity is advantageous in plants in nutrient poor soils, as the loss of valuable nutrients in leaf loss is minimised (the leaves store much of a plants' nutrients).
Cultivation
Although somewhat resistant to diebackPhytophthora cinnamomi
Phytophthora cinnamomi is a soil-borne water mould that produces an infection which causes a condition in plants called root rot or dieback. The plant pathogen is one of the world's most invasive species and is present in over 70 countries from around the world.- Life cycle and effects on plants :P...
, it does require a well drained soil, preferably fairly sandy. Like other banksias, it grows best in full sun. It makes an attractive prostrate groundcover, and can be used in embankments and to reduce soil erosion, as well as rockeries. It is tolerant of alkaline soils, with one cultivated specimen recorded tolerating a pH of 9.5. Seeds do not require any treatment, and takes about 18 to 49 days to germinate.