Banksia xylothemelia
Encyclopedia
Banksia xylothemelia is a sprawling woody shrub
of the Proteaceae
family endemic to southern Western Australia
, one of the many species commonly known as dryandras and until recently called Dryandra xylothemelia. To date it is almost unknown in cultivation.
s arising from an underground lignotuber
. It has woolly
stems, and Leaves are pinnatifid with five to nine leaflets on each side, 7 to 12 centimetres long, 4 to 5.5 centimetres wide, smooth above but woolly beneath. Flowers occur in dome shaped heads up to four centimetres across, attached directly to an older stem, or on a short stalk. Flower heads contain from 80 to 100 bright yellow flowers. Each flower consists of a tubular perianth
made up of four fused tepal
s, and one long wiry style. The styles are hooked rather than straight, and are initially trapped inside the upper perianth parts, but break free at anthesis
. Seeds are produced in follicles
embedded in the woody bases of the flower heads.
by Robert M. Buehrig on 9 December 1993, and a specimen collected from west of Lake King
by P. G. Wilson. On 11 October 1994, Alex George
collected what would later become the type specimen, from a location on the Holt Rock South Road, 14 kilometres north of Newdigate-Lake King Road, at 32°58′S 119°23′E.
Two years later, George published a formal description of the species in Nuytsia
10(3), placing it in genus Dryandra
, subgenus Dryandra and series Armatae. He gave it the specific name "xylothemelia", from the Greek
"xylon" (wood) and "themelios" (foundation), in reference to species' lignotuber
, the possession of which distinguishes it from its close relative B. cirsioides
; thus the full name of the species was for a time Dryandra xylothemelia A.S.George.
Early in 2007, Austin Mast
and Kevin Thiele
transferred all Dryandra taxa to Banksia. The current name for this species is therefore Banksia xylothemelia (A.S.George) A.R.Mast & K.R.Thiele. As an interim measure, Mast and Thiele placed all but one Dryandra taxon in Banksia ser. Dryandra.
It occurs in sand over laterite
or in gravelly loam, amongst heath
or sometimes mallee woodlands and shrublands
. It occurs only within the Esperance Plains
and Mallee
biogeographic
region, between Kulin
, Lake Magenta
, Frank Hann National Park
and Hyden
.
, B. xylothemelia has proteoid root
s, roots with dense clusters of short lateral rootlets that form a mat in the soil just below the leaf litter. These enhance solubilisation of nutrients, thus allowing nutrient uptake in low-nutrient soils such as the phosphorus
-deficient native soils of Australia. It has a lignotuber, so is able to resprout after being burned to the ground by bushfire.
It has been given a rating of "Priority Three - Poorly Known Taxa" on Western Australia's Department of Environment and Conservation's Declared Rare and Priority Flora List.
An assessment of the potential impact of climate change
on this species found that its range is likely to contract by half under mild change, and severe change is likely to lead to extinction
unless it migrates rapidly into newly habitable areas.
and other heavy soils, and tolerates dry conditions and moderate frosts once established. Tony Cavanagh and Margaret Pieroni
suggest that it would be best suited to a small garden in a warm sunny area. Seed takes six to seven weeks to germinate; germination rates appear to be quite low, with most reports suggesting success rates of less than 30%.
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 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 endemic to southern 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...
, one of the many species commonly known as dryandras and until recently called Dryandra xylothemelia. To date it is almost unknown in cultivation.
Description
It grows as a sprawling shrub up to one metre (3 ft) high, often with basal shootBasal shoot
A basal shoot, root sprout, adventitious shoot, water sprout or sucker is a shoot or cane which grows from a bud at the base of a tree or shrub or from its roots. This shoot then becomes, or takes the form of, a singular plant. A plant that produces suckers is referred to as surculose...
s arising from an underground lignotuber
Lignotuber
A lignotuber is a starchy swelling of the root crown possessed by some plants as a protection against destruction of the plant stem by fire. The crown contains buds from which new stems may sprout, and a sufficient store of nutrients to support a period of growth in the absence of...
. It has woolly
Tomentose
Tomentose is a term used to describe plant hairs that are flattened and matted, forming a woolly coating known as tomentum. Often the hairs are silver or gray-colored...
stems, and Leaves are pinnatifid with five to nine leaflets on each side, 7 to 12 centimetres long, 4 to 5.5 centimetres wide, smooth above but woolly beneath. Flowers occur in dome shaped heads up to four centimetres across, attached directly to an older stem, or on a short stalk. Flower heads contain from 80 to 100 bright yellow flowers. Each flower consists of a tubular perianth
Perianth
The term perianth has two similar but separate meanings in botany:* In flowering plants, the perianth are the outer, sterile whorls of a flower...
made up of four fused tepal
Tepal
Tepals are elements of the perianth, or outer part of a flower, which include the petals or sepals. The term tepal is more often applied specifically when all segments of the perianth are of similar shape and color, or undifferentiated, which is called perigone...
s, and one long wiry style. The styles are hooked rather than straight, and are initially trapped inside the upper perianth parts, but break free at anthesis
Anthesis
Anthesis is the period during which a flower is fully open and functional. It may also refer to the onset of that period.The onset of anthesis is spectacular in some species. In Banksia species, for example, anthesis involves the extension of the style far beyond the upper perianth parts...
. Seeds are produced in follicles
Follicle (fruit)
In botany, a follicle is a dry unilocular many-seeded fruit formed from one carpel and dehiscing by the ventral suture in order to release seeds, such as in larkspur, magnolia, banksia, peony and milkweed....
embedded in the woody bases of the flower heads.
Taxonomy
Early collections of B. xylothemelia include a specimen collected in the Dragon Rocks Nature ReserveDragon Rocks Nature Reserve
Dragon Rocks is a 322 km2 nature reserve in the south-east of the wheatbelt region of Western Australia, some 310 km east-south-east of Perth. It is surrounded by farmland...
by Robert M. Buehrig on 9 December 1993, and a specimen collected from west of Lake King
Lake King, Western Australia
Lake King is a town located in the Eastern Wheatbelt region of Western Australia, from Perth along State Route 107 between Wagin and Ravensthorpe....
by P. G. Wilson. On 11 October 1994, Alex George
Alex George
Alexander Segger George is a Western Australian botanist. He is the authority on the plant genera Banksia and Dryandra...
collected what would later become the type specimen, from a location on the Holt Rock South Road, 14 kilometres north of Newdigate-Lake King Road, at 32°58′S 119°23′E.
Two years later, George published a formal description of the species in Nuytsia
Nuytsia (journal)
Nuytsia is a peer-reviewed journal published by the Western Australian Herbarium. It publishes papers on systematic botany, giving preference to papers related to the flora of Western Australia. Nearly twenty percent of Western Australia's plant taxa have been published in Nuytsia. First published...
10(3), placing it in genus Dryandra
Dryandra
Banksia ser. Dryandra is a series of 94 species of shrub to small tree in the plant genus Banksia. It was considered a separate genus named Dryandra until early 2007, when it was merged into Banksia on the basis of extensive molecular and morphological evidence that Banksia was paraphyletic with...
, subgenus Dryandra and series Armatae. He gave it the specific name "xylothemelia", from the Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
"xylon" (wood) and "themelios" (foundation), in reference to species' lignotuber
Lignotuber
A lignotuber is a starchy swelling of the root crown possessed by some plants as a protection against destruction of the plant stem by fire. The crown contains buds from which new stems may sprout, and a sufficient store of nutrients to support a period of growth in the absence of...
, the possession of which distinguishes it from its close relative B. cirsioides
Banksia cirsioides
Banksia cirsioides is a shrub endemic to Western Australia. It was known as Dryandra cirsioides until 2007, when all Dryandra species were transferred to Banksia by Austin Mast and Kevin Thiele.-Description:...
; thus the full name of the species was for a time Dryandra xylothemelia A.S.George.
Early in 2007, 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...
and 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...
transferred all Dryandra taxa to Banksia. The current name for this species is therefore Banksia xylothemelia (A.S.George) A.R.Mast & K.R.Thiele. As an interim measure, Mast and Thiele placed all but one Dryandra taxon in Banksia ser. Dryandra.
Distribution and habitat
Laterite
Laterites are soil types rich in iron and aluminium, formed in hot and wet tropical areas. Nearly all laterites are rusty-red because of iron oxides. They develop by intensive and long-lasting weathering of the underlying parent rock...
or in gravelly loam, amongst heath
Heath (habitat)
A heath or heathland is a dwarf-shrub habitat found on mainly low quality acidic soils, characterised by open, low growing woody vegetation, often dominated by plants of the Ericaceae. There are some clear differences between heath and moorland...
or sometimes mallee woodlands and shrublands
Mallee Woodlands and Shrublands
Mallee Woodlands and Shrublands is a Major Vegetation Group which occurs in semi-arid areas of southern Australia. The vegetation is dominated by mallee eucalypts which are rarely over 6 metres high...
. It occurs only within the Esperance Plains
Esperance Plains
Esperance Plains, also known as Eyre Botanical District, is a biogeographic region in southern Western Australia. Located on the south coast between the Avon Wheatbelt and Hampton regions, and bordered to the north by the Mallee region, it is a plain punctuated by granite and quartz outcrops and...
and Mallee
Mallee (biogeographic region)
Mallee, also known as Roe Botanical District, is a biogeographic region in southern Western Australia. Located between the Esperance Plains, Avon Wheatbelt and Coolgardie regions, it has a low, gently undulating topography, a semi-arid mediterranean climate, and extensive Eucalyptus mallee...
biogeographic
Biogeography
Biogeography is the study of the distribution of species , organisms, and ecosystems in space and through geological time. Organisms and biological communities vary in a highly regular fashion along geographic gradients of latitude, elevation, isolation and habitat area...
region, between Kulin
Kulin, Western Australia
Kulin is a town located in the Eastern Wheatbelt region of Western Australia, approximately 280 km from Perth. It is the main town in the Shire of Kulin.- History :...
, Lake Magenta
Lake Magenta
Lake Magenta is an ephemeral salt lake in the Wheatbelt area of Western Australia.The lake is located approximately North East of Jerramungup and approximately West of Ravensthorpe....
, Frank Hann National Park
Frank Hann National Park
Frank Hann National Park is a national park in Western Australia , located east-southeast of the capital, Perth in the Shire of Lake Grace. It was named for Frank Hann, an early explorer of the district...
and Hyden
Hyden, Western Australia
The town of Hyden is located 339 km east of Perth, Western Australia in the Shire of Kondinin. Hyden is home to Wave Rock and Mulka's Cave, both popular local tourist attractions....
.
Ecology
Like most other ProteaceaeProteaceae
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,...
, B. xylothemelia has proteoid root
Proteoid root
Proteoid roots, also known as cluster roots, are plant roots that form clusters of closely spaced short lateral rootlets. They may form a two to five centimetre thick mat just beneath the leaf litter. They enhance nutrient uptake, possibly by chemically modifying the soil environment to improve...
s, roots with dense clusters of short lateral rootlets that form a mat in the soil just below the leaf litter. These enhance solubilisation of nutrients, thus allowing nutrient uptake in low-nutrient soils such as the phosphorus
Phosphorus
Phosphorus is the chemical element that has the symbol P and atomic number 15. A multivalent nonmetal of the nitrogen group, phosphorus as a mineral is almost always present in its maximally oxidized state, as inorganic phosphate rocks...
-deficient native soils of Australia. It has a lignotuber, so is able to resprout after being burned to the ground by bushfire.
It has been given a rating of "Priority Three - Poorly Known Taxa" on Western Australia's Department of Environment and Conservation's Declared Rare and Priority Flora List.
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 half under mild change, and severe change is likely to lead to extinction
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
unless it migrates rapidly into newly habitable areas.
Cultivation
B. xylothemelia is rarely cultivated. It prefers lateriticLaterite
Laterites are soil types rich in iron and aluminium, formed in hot and wet tropical areas. Nearly all laterites are rusty-red because of iron oxides. They develop by intensive and long-lasting weathering of the underlying parent rock...
and other heavy soils, and tolerates dry conditions and moderate frosts once established. Tony Cavanagh and Margaret Pieroni
Margaret Pieroni
Margaret Pieroni is a Western Australian botanical artist and botanist who has authored, co-authored and/or illustrated numerous books on Australian botany, including Brush with Gondwana: Botanical Artists Group of Western Australia , The Dryandras , Verticordia: the turner of hearts , Discovering...
suggest that it would be best suited to a small garden in a warm sunny area. Seed takes six to seven weeks to germinate; germination rates appear to be quite low, with most reports suggesting success rates of less than 30%.