Banksia is a
genusIn biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of around 170
speciesIn biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
in the
plantPlants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
familyIn biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
ProteaceaeProteaceae 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,...
. These
AustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
n
wildflowerA wildflower is a flower that grows wild, meaning it was not intentionally seeded or planted. Yet "wildflower" meadows of a few mixed species are sold in seed packets. The term "wildflower" has been made vague by commercial seedsmen who are interested in selling more flowers or seeds more...
s and popular
garden plantOrnamental plants are plants that are grown for decorative purposes in gardens and landscape design projects, as house plants, for cut flowers and specimen display...
s are easily recognised by their characteristic flower spikes and fruiting "cones" and heads. When it comes to size, banksias range from prostrate woody
shrubA 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...
s to trees up to 30 metres tall. They are generally found in a wide variety of landscapes;
sclerophyllSclerophyll is the term for a type of vegetation that has hard leaves and short internodes . The word comes from the Greek sclero and phyllon ....
forest, (occasionally) rainforest, shrubland, and some more arid landscapes, though not in Australia's deserts.
Heavy producers of
nectarNectar is a sugar-rich liquid produced by plants. It is produced in glands called nectaries, either within the flowers, in which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists, which in turn provide anti-herbivore protection...
, banksias form a vital part of the food chain in the Australian bush. They are an important food source for all sorts of nectariferous animals, including birds, bats, rats, possums, stingless bees and a host of invertebrates. Furthermore, they are of economic importance to Australia's
nurseryA nursery is a place where plants are propagated and grown to usable size. They include retail nurseries which sell to the general public, wholesale nurseries which sell only to businesses such as other nurseries and to commercial gardeners, and private nurseries which supply the needs of...
and
cut flowerFloristry is the general term used to describe production, commerce and trade in flowers. It encompasses flower care and handling, floral design or flower arranging, merchandising, and display and flower delivery. Wholesale florists sell bulk flowers and related supplies to professionals in the trade...
industries. However these plants are threatened by a number of processes including
land clearingLand clearing in Australia describes the removal of native vegetation and deforestation and in Australia. Land clearing involves the removal of native vegetation and habitats, including the bulldozing of native bushlands, forests, savannah, woodlands and native grasslands and the draining of...
, frequent burning and disease, and a number of species are
rareA rare species is a group of organisms that are very uncommon or scarce. This designation may be applied to either a plant or animal taxon, and may be distinct from the term "endangered" or "threatened species" but not "extinct"....
and
endangeredAn endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
.
Description
Banksias grow as
treeA tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to...
s or woody shrubs. Trees of the largest species,
B. integrifoliaBanksia integrifolia, commonly known as Coast Banksia, is a species of tree that grows along the east coast of Australia. One of the most widely distributed Banksia species, it occurs between Victoria and Central Queensland in a broad range of habitats, from coastal dunes to mountains...
(Coast Banksia) and
B. seminudaBanksia seminuda, commonly known as the River Banksia, is a tree in the plant genus Banksia. It is found in south west Western Australia from Dwellingup to the Broke Inlet east of Denmark . It is often mistaken for and was originally considered a subspecies of the Banksia littoralis...
(River Banksia), often grow over 15 metres tall, some even grow to standing 30 metres tall. Banksia species that grow as shrubs are usually erect, but there are several species that are prostrate, with branches that grow on or below the soil.
The leaves of Banksia vary greatly between species. Sizes vary from the narrow, 1–1½ centimetre long leaves of
B. ericifoliaBanksia ericifolia, the Heath-leaved Banksia , is a species of woody shrub of the Proteaceae family native to Australia. It grows in two separate regions of Central and Northern New South Wales east of the Great Dividing Range...
(Heath-leaved Banksia), to the very large leaves of
B. grandisBanksia grandis, commonly known as Bull Banksia, Giant Banksia or Mangite, is a common and distinctive tree in South West Western Australia....
(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
whorlsIn botany, a whorl is an arrangement of sepals, petals, leaves, or branches in which all the parts are attached at the same point and surround or wrap around the stem.There are four whorls in a general flower...
. Many species have differing juvenile and adult leaves (e.g. Banksia integrifolia has large serrated juvenile leaves).
The character most commonly associated with Banksia is the flower spike, an elongated
inflorescenceAn 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...
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. grandisBanksia grandis, commonly known as Bull Banksia, Giant Banksia or Mangite, is a common and distinctive tree in South West Western Australia....
. Not all Banksia have an elongate flower spike, however: the members of the small
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...
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. Thus fewer than half of the currently accepted Banksia taxa possess the elongated flower spike long considered characteristic of the genus.
Banksia flowers are usually a shade of
yellowYellow is the color evoked by light that stimulates both the L and M cone cells of the retina about equally, with no significant stimulation of the S cone cells. Light with a wavelength of 570–590 nm is yellow, as is light with a suitable mixture of red and green...
, but
orangeThe colour orange occurs between red and yellow in the visible spectrum at a wavelength of about 585–620 nm, and has a hue of 30° in HSV colour space. It is numerically halfway between red and yellow in a gamma-compressed RGB colour space, the expression of which is the RGB colour wheel. The...
,
redRed is any of a number of similar colors evoked by light consisting predominantly of the longest wavelengths of light discernible by the human eye, in the wavelength range of roughly 630–740 nm. Longer wavelengths than this are called infrared , and cannot be seen by the naked eye...
,
pinkPink is a mixture of red and white. Commonly used for Valentine's Day and Easter, pink is sometimes referred to as "the color of love." The use of the word for the color known today as pink was first recorded in the late 17th century....
and even
violetAs the name of a color, violet is synonymous with a bluish purple, when the word "purple" is used in the common English language sense of any color between blue and red, not including either blue or red...
flowers also occur. The colour of the flowers is determined by the colour of the
perianthThe term perianth has two similar but separate meanings in botany:* In flowering plants, the perianth are the outer, sterile whorls of a flower...
parts and often the style. The style is much longer than the perianth, and is initially trapped by the upper perianth parts. These are gradually released over a period of days, either from top to bottom or from bottom to top. When the styles and perianth parts are different colours, the visual effect is of a colour change sweeping along the spike. This can be most spectacular in
B. prionotesBanksia prionotes, commonly known as Acorn Banksia or Orange Banksia, is a species of shrub or tree of the genus Banksia in the family Proteaceae. It is native to the southwest of Western Australia and can reach up to 10 m in height. It can be much smaller in more exposed areas or in the...
(Acorn Banksia) and related species, as the white inflorescence in bud becomes a brilliant orange. In most cases, the individual flowers are tall, thin saccate (sack-shaped) in shape.
Occasionally, multiple flower spikes can form. This is most often seen in
Banksia marginataBanksia marginata, commonly known as the Silver Banksia, is a species of tree or woody shrub in the plant genus Banksia found throughout much of southeastern Australia. It ranges from the Eyre Peninsula in South Australia, to north of Armidale, New South Wales, and across Tasmania and the islands...
and
B. ericifoliaBanksia ericifolia, the Heath-leaved Banksia , is a species of woody shrub of the Proteaceae family native to Australia. It grows in two separate regions of Central and Northern New South Wales east of the Great Dividing Range...
(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:
conesA cone is an organ on plants in the division Pinophyta that contains the reproductive structures. The familiar woody cone is the female cone, which produces seeds. The male cones, which produce pollen, are usually herbaceous and much less conspicuous even at full maturity...
only occur in conifers and
cycadCycads are seed plants typically characterized by a stout and woody trunk with a crown of large, hard and stiff, evergreen leaves. They usually have pinnate leaves. The individual plants are either all male or all female . Cycads vary in size from having a trunk that is only a few centimeters...
s.
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
follicleIn 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 axis of the inflorescence. These consist of two horizontal valves that tightly enclose the seeds. The follicle opens to release the seed by splitting along the suture, and 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
The Banksia genus was first described and named by
Carolus Linnaeus the YoungerCarl Linnaeus the Younger, Carl von Linné or Carolus Linnaeus the Younger was a Swedish naturalist...
in his April 1782 publication
Supplementum PlantarumSupplementum Plantarum Systematis Vegetabilium Editionis Decimae Tertiae, Generum Plantarum Editiones Sextae, et Specierum Plantarum Editionis Secundae, commonly abbreviated to Supplementum Plantarum Systematis Vegetabilium or just Supplementum Plantarum, and further abbreviated by botanists to...
; hence the full name for the genus is "Banksia L.f." The genus name honours the
EnglishEngland is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
botanist Sir
Joseph BanksSir Joseph Banks, 1st Baronet, GCB, PRS was an English naturalist, botanist and patron of the natural sciences. He took part in Captain James Cook's first great voyage . Banks is credited with the introduction to the Western world of eucalyptus, acacia, mimosa and the genus named after him,...
, who collected the first Banksia specimens in 1770, during
James CookCaptain James Cook, FRS, RN was a British explorer, navigator and cartographer who ultimately rose to the rank of captain in the Royal Navy...
's first expedition.
Banksia belongs to the family
ProteaceaeProteaceae 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,...
, subfamily
GrevilleoideaeGrevilleoideae is a subfamily of the Proteaceae family of flowering plants. Mainly restricted to the southern hemisphere, it contains around 44 genera and about 950 species. Genera include Banksia, Grevillea and Macadamia.-Description:...
, and tribe Banksieae. There are around 170 species.
Distribution and habitat
All but one of the living Banksia species are
endemicEndemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...
to Australia. The exception is
B. dentataThe Tropical Banksia is a species of small tree in the plant genus Banksia.-Distribution and habitat:It occurs throughout northern Australia, and also extends into New Guinea and the Aru Islands...
(Tropical Banksia), which occurs throughout northern Australia, and on islands to the north including
New GuineaNew Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
and the
Aru IslandsThe Aru Islands are a group of about ninety-five low-lying islands in the Maluku province of eastern Indonesia. They also form a regency of Indonesia.-Geography:...
. An extinct species,
B. novae-zelandiaeBanksia novae-zelandiae is an extinct species of Banksia, known only from fossil leaves found on the South Island of New Zealand.-Description:...
, was found in
New ZealandNew Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
. The other species occur in two distinct geographical regions:
southwestSouthwest Australia is a biodiversity hotspot that includes the Mediterranean forests, woodlands, and scrub ecoregions of Western Australia. The region has a wet-winter, dry-summer Mediterranean climate, one of five such regions in the world...
Western AustraliaWestern 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 eastern Australia. Southwest Western Australia is the main centre of
biodiversityBiodiversity is the degree of variation of life forms within a given ecosystem, biome, or an entire planet. Biodiversity is a measure of the health of ecosystems. Biodiversity is in part a function of climate. In terrestrial habitats, tropical regions are typically rich whereas polar regions...
; over 90% of all Banksia species occur only there, from
Exmouth-Further reading:* Western Australia. Ministry for Planning. Exmouth-Learmonth structure plan. Perth, W.A. : Western Australian Planning Commission...
in the north, south and east to beyond
EsperanceEsperance 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,...
on the south coast. Eastern Australia has far fewer species, but these include some of best known and most widely distributed species, including
B. integrifoliaBanksia integrifolia, commonly known as Coast Banksia, is a species of tree that grows along the east coast of Australia. One of the most widely distributed Banksia species, it occurs between Victoria and Central Queensland in a broad range of habitats, from coastal dunes to mountains...
(Coast Banksia) and
B. spinulosaThe Hairpin Banksia is a species of woody shrub, of the genus Banksia in the Proteaceae family, native to eastern Australia. Widely distributed, it is found as an understorey plant in open dry forest or heathland from Victoria to northern Queensland, generally on sandstone though sometimes also...
(Hairpin Banksia). Here they occur from the
Eyre PeninsulaEyre Peninsula is a triangular peninsula in South Australia. It is bounded on the east by Spencer Gulf, the west by the Great Australian Bight, and the north by the Gawler Ranges. It is named after explorer Edward John Eyre who explored some of it in 1839-1841. The coastline was first explored by...
in South Australia right around the east coast up to
Cape YorkCape York Peninsula is a large remote peninsula located in Far North Queensland at the tip of the state of Queensland, Australia, the largest unspoilt wilderness in northern Australia and one of the last remaining wilderness areas on Earth...
in
QueenslandQueensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
.
The vast majority of Banksia are found in sandy or gravelly soils, though some populations of
B. marginataBanksia marginata, commonly known as the Silver Banksia, is a species of tree or woody shrub in the plant genus Banksia found throughout much of southeastern Australia. It ranges from the Eyre Peninsula in South Australia, to north of Armidale, New South Wales, and across Tasmania and the islands...
(Silver Banksia) and B. spinulosa do occur on heavier, more clay-like, soils. B. seminuda is exceptional for its preference for rich loams along watercourses.
Most occur in
heathlandsA 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 low
woodlandEcologically, a woodland is a low-density forest forming open habitats with plenty of sunlight and limited shade. Woodlands may support an understory of shrubs and herbaceous plants including grasses. Woodland may form a transition to shrubland under drier conditions or during early stages of...
s; of the eastern species, B. integrifolia and B. marginata occur in forests; many south-western species such as
B. grandisBanksia grandis, commonly known as Bull Banksia, Giant Banksia or Mangite, is a common and distinctive tree in South West Western Australia....
,
B. sphaerocarpaBanksia sphaerocarpa, commonly known as the Fox Banksia or Round-fruit Banksia, is a species of shrub or tree in the plant genus Banksia . It is generally encountered as a 1–2 m high shrub, and is usually smaller in the north of its range...
, B. sessilis,
B. nobilisBanksia nobilis, commonly known as Golden Dryandra, Great Dryandra or Kerosene Bush, is a shrub endemic to Western Australia. It occurs on lateritic rises from Eneabba to Katanning in the state's Southwest Botanic Province. With large pinnatifid leaves with triangular lober, and a golden or reddish...
and B. dallanneyi grow as understorey plants in
JarrahEucalyptus marginata is one of the most common species of Eucalyptus tree in the southwest of Western Australia. The tree and the wood are usually referred to by the Aboriginal name Jarrah...
(Eucalyptus marginata), Wandoo (E. wandoo) and Karri (E. diversicolor)
forestA forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
s, with B. seminuda being one of the forest trees in suitable habitat.
Most species do not grow well near the
coastA coastline or seashore is the area where land meets the sea or ocean. A precise line that can be called a coastline cannot be determined due to the dynamic nature of tides. The term "coastal zone" can be used instead, which is a spatial zone where interaction of the sea and land processes occurs...
, notable exceptions being the southern
Western AustraliaWestern 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...
n species
B. speciosaThe Showy Banksia is a species of large shrub or small tree in the plant genus Banksia. It reaches up to 8 m in height...
,
B. praemorsaThe Cut-leaf Banksia is a species of shrub or tree in the plant genus Banksia. It occurs in a few isolated populations on the south coast of Western Australia between Albany and Cape Riche. Seeds do not require any treatment, and take 30 to 49 days to germinate.-References:...
and
B. 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....
. Only a few species, such as
B. rosseraeBanksia rosserae is a recently described species of Banksia. Endemic to inland Western Australia, it is the only Banksia species to occur solely within the arid zone.-Description:...
and
B. elderianaThe 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...
(Swordfish Banksia), occur in
aridA desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...
areas. Most of the eastern Australian species survive in uplands, but only a few of the
Western AustraliaWestern 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...
n species native to the
Stirling RangeThe Stirling Range or Koikyennuruff is a range of mountains and hills in the Great Southern region of Western Australia, 337 km south-east of Perth. It is located at approximately and is over 60 km wide from west to east, stretching from the highway between Mount Barker and Cranbrook...
s -
B. solandriBanksia solandri, commonly known as Stirling Range Banksia, is a species of large shrub in the plant genus Banksia. It occurs only within the Stirling Range in southwest Western Australia.-Description:...
,
B. oreophilaThe Western Mountain Banksia or Mountain Banksia is a species of shrub in the plant genus Banksia. It occurs on the slopes and hilltops of the Stirling and Barren Ranges in southwest Western Australia.-Taxonomy:...
,
B. browniiBanksia brownii, commonly known as Feather-leaved Banksia or Brown's Banksia, is a species of shrub that occurs in southwest Western Australia. An attractive plant with fine feathery leaves and large red-brown flower spikes, it usually grows as an upright bush around two metres high, but can also...
and
B. montanaBanksia montana is a shrub endemic to Western Australia....
- survive at high altitudes.
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 the genus' range tend to have fewer species with larger distributions. The greatest species richness occurs in association with uplands, especially the Stirling Range.
Ecology
Banksias are heavy producers of
nectarNectar is a sugar-rich liquid produced by plants. It is produced in glands called nectaries, either within the flowers, in which it attracts pollinating animals, or by extrafloral nectaries, which provide a nutrient source to animal mutualists, which in turn provide anti-herbivore protection...
, making them an important source of food for nectivorous animals, including honeyeaters and small mammals such as rodents, antechinus,
honey possumThe honey possum or tait, its Native Australian name or noolbenger is a tiny Australian marsupial weighing just seven to eleven grams for the male, and eight to sixteen grams for the female—about half the weight of a mouse. Their physical size ranges from a body length of between 6.5 –...
s,
pygmy possumThe pygmy possums are a family of small possums that together form the marsupial family Burramyidae. There are five extant species of pygmy possum, grouped into two genera. Four of the species are endemic to Australia, with one species also co-occurring in Papua New Guinea and Indonesia.Pygmy...
s, gliders and
batBats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...
s. Many of these animals play a role in pollination of Banksia. Various studies have shown mammals and birds to be important pollinators.
An interesting observation by Carpenter in 1978 was that some banksias had a stronger odour at night possibly to attract mammal pollinators.
Other associated fauna include the
larvaA larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e of
mothA moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...
s (such as the
Dryandra MothThe Dryandra Moth is a species of moth. It is considered the only species in the family Carthaeidae. Its closest relatives are the Saturniidae and it bears a resemblance to many species of that family, bearing prominent eye spots on all wings. The wingspan is up to 10 cm...
) and
weevilA weevil is any beetle from the Curculionoidea superfamily. They are usually small, less than , and herbivorous. There are over 60,000 species in several families, mostly in the family Curculionidae...
s, which burrow into the "cones" to eat the seeds and
pupaA pupa is the life stage of some insects undergoing transformation. The pupal stage is found only in holometabolous insects, those that undergo a complete metamorphosis, going through four life stages; embryo, larva, pupa and imago...
te in the follicles; and
birdBirds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
s such as
cockatooA cockatoo is any of the 21 species belonging to the bird family Cacatuidae. Along with the Psittacidae and the Strigopidae , they make up the parrot order Psittaciformes . Placement of the cockatoos as a separate family is fairly undisputed, although many aspects of the other living lineages of...
s, who break off the "cones" to eat both the seeds and the
insectInsects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
larvae.
A number of Banksia species are considered rare or endangered. These include
B. browniiBanksia brownii, commonly known as Feather-leaved Banksia or Brown's Banksia, is a species of shrub that occurs in southwest Western Australia. An attractive plant with fine feathery leaves and large red-brown flower spikes, it usually grows as an upright bush around two metres high, but can also...
(Feather-leaved Banksia),
B. cuneataBanksia cuneata, commonly known as Matchstick Banksia or Quairading Banksia, is an endangered species of flowering plants in the Proteaceae family. Endemic to southwest Western Australia, it belongs to Banksia subg...
(Matchstick Banksia),
B. 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...
(Good's Banksia),
B. oliganthaBanksia oligantha, commonly known as Wagin Banksia, is an endangered species in the plant family Proteaceae endemic to south west Western Australia. It belongs to Banksia subg. Isostylis, a subgenus of three closely related Banksia species with dome-shaped heads as inflorescences, rather than...
(Wagin Banksia),
B. tricuspisThe Lesueur Banksia or Pine Banksia is a species of shrub or tree in the plant genus Banksia. It occurs within a geographic range of just 15 square kilometres near Jurien, Western Australia.-External links:...
(Pine Banksia), and
B. verticillataBanksia verticillata, commonly known as Granite Banksia or Albany Banksia, is a species of shrub or tree of the genus Banksia in the Proteaceae family. It is native to the southwest of Western Australia and can reach up to 3 m in height. It can grow taller to 5 m in sheltered areas,...
(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 because they have very thick bark that protects the trunk from fire, or because they have
lignotuberA 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...
s from which they can resprout after fire. In
Western AustraliaWestern 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...
, banksias of the first group are known as 'seeders' and the second group as 'sprouters'.
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. 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
water mouldOömycota or oömycetes form a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms . They are filamentous, microscopic, absorptive organisms that reproduce both sexually and asexually...
Phytophthora cinnamomiPhytophthora 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...
, commonly known as "dieback". Dieback attacks the roots of plants, destroying the structure of the root tissues, "rotting" the root, and preventing the plant from absorbing water and nutrients. Banksias
proteoid rootProteoid 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, which help it to survive in low-nutrient soils, make it highly susceptible to this
diseaseA disease is an abnormal condition affecting the body of an organism. It is often construed to be a medical condition associated with specific symptoms and signs. It may be caused by external factors, such as infectious disease, or it may be caused by internal dysfunctions, such as autoimmune...
. All Western Australian species are vulnerable, although most eastern species are fairly resistant.
Vulnerable plants typically die within a few years of infection. In
southwestSouthwest Australia is a biodiversity hotspot that includes the Mediterranean forests, woodlands, and scrub ecoregions of Western Australia. The region has a wet-winter, dry-summer Mediterranean climate, one of five such regions in the world...
Western Australia, where dieback infestation is widespread, infested areas of Banksia forest typically have less than 30% of the cover of uninfested areas. Plant deaths in such large proportions can have a profound influence on the makeup of plant communities. For example, in southwestern Australia Banksia often occurs as an understorey to forests of
JarrahEucalyptus marginata is one of the most common species of Eucalyptus tree in the southwest of Western Australia. The tree and the wood are usually referred to by the Aboriginal name Jarrah...
(Eucalyptus marginata), another species highly vulnerable to dieback. Infestation kills both the Jarrah overstorey and the original Banksia understorey, and over time these may be replaced by a more open woodland consisting of an overstorey of the resistant Marri (
Corymbia calophyllaCorymbia calophylla is a bloodwood native to Western Australia. Common names include Marri and Port Gregory Gum, and a long standing usage has been Red Gum due to the red gum effusions often found on trunks.It is distinctive among bloodwoods for its very large buds and fruit Corymbia calophylla...
), and an understorey of the somewhat resistant Banksia sessilis (Parrotbush).
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. Other vulnerable species include B. cuneata, and B. verticillata.
Dieback is notoriously difficult to treat, although there has been some success with
phosphiteA phosphite is a salt of phosphorous acid. The phosphite ion is a polyatomic ion with a phosphorus central atom where phosphorus has an oxidation state of +3...
and
phosphorous acidPhosphorous acid is the compound described by the formula H3PO3. This acid is diprotic , not triprotic as might be suggested by this formula. Phosphorous acid is as an intermediate in the preparation of other phosphorus compounds.-Nomenclature and tautomerism:H3PO3 is more clearly described with...
, which are currently used to inoculate wild B. brownii populations. However this is not without potential problems as it alters the soil composition by adding
phosphorusPhosphorus 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...
. Some evidence suggests that phosphorous acid may inhibit proteoid root formation.
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
In the garden
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. integrifoliaBanksia integrifolia, commonly known as Coast Banksia, is a species of tree that grows along the east coast of Australia. One of the most widely distributed Banksia species, it occurs between Victoria and Central Queensland in a broad range of habitats, from coastal dunes to mountains...
having its subspecies
B. integrifolia subsp. monticolaBanksia integrifolia subsp. monticola, commonly known as White Mountain Banksia, is a subspecies of Banksia integrifolia. Described in 1994, it occurs in the Blue Mountains in northern New South Wales. It contains the largest recorded Banksia trees.-Description:B. integrifolia subsp. monticola...
notable for reaching the biggest banksias and it is the most frost tolerant in this genus,
B. seminudaBanksia seminuda, commonly known as the River Banksia, is a tree in the plant genus Banksia. It is found in south west Western Australia from Dwellingup to the Broke Inlet east of Denmark . It is often mistaken for and was originally considered a subspecies of the Banksia littoralis...
,
B. littoralisBanksia littoralis, commonly known as the Swamp Banksia, Swamp Oak, Pungura and the Western Swamp Banksia, is a tree in the plant genus Banksia. It is found in south west Western Australia from the south eastern metropolitan area of Perth to the Stirling Range and Albany...
,
B. serrataBanksia serrata, commonly known as Old Man Banksia, Saw Banksia, Saw-tooth Banksia and Red Honeysuckle, is a species of woody shrub or tree of the genus Banksia in the Proteaceae family. Native the east coast of Australia, it is found from Queensland through to Victoria with outlying populations on...
; species that can grow as small trees or big shrubs:
B. grandisBanksia grandis, commonly known as Bull Banksia, Giant Banksia or Mangite, is a common and distinctive tree in South West Western Australia....
,
B. prionotesBanksia prionotes, commonly known as Acorn Banksia or Orange Banksia, is a species of shrub or tree of the genus Banksia in the family Proteaceae. It is native to the southwest of Western Australia and can reach up to 10 m in height. It can be much smaller in more exposed areas or in the...
,
B. marginataBanksia marginata, commonly known as the Silver Banksia, is a species of tree or woody shrub in the plant genus Banksia found throughout much of southeastern Australia. It ranges from the Eyre Peninsula in South Australia, to north of Armidale, New South Wales, and across Tasmania and the islands...
,
B. coccineaBanksia coccinea, commonly known as the Scarlet Banksia, Waratah Banksia or Albany Banksia, is an erect shrub or small tree in the plant genus Banksia...
,
B. speciosaThe Showy Banksia is a species of large shrub or small tree in the plant genus Banksia. It reaches up to 8 m in height...
and
B. menziesiiBanksia menziesii, commonly known as firewood banksia, is a species of flowering plant in the genus Banksia. It is a gnarled tree up to 10 m tall, or a lower spreading 1–3 m shrub in the more northern parts of its range. The serrated leaves are dull green with new growth a paler grey...
. 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 nectar they produce attracts birds and small
mammalMammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s. Popular garden species include B. spinulosa, B. ericifolia,
B. aemulaBanksia aemula, commonly known as the wallum banksia, is a lignotuberous shrub of the Proteaceae family. Found from Bundaberg south to Sydney on the Australian east coast, it is encountered as a shrub or a taller tree to 8 m in coastal heath on deep sandy soil, known as Wallum...
(Wallum Banksia ),
B. serrataBanksia serrata, commonly known as Old Man Banksia, Saw Banksia, Saw-tooth Banksia and Red Honeysuckle, is a species of woody shrub or tree of the genus Banksia in the Proteaceae family. Native the east coast of Australia, it is found from Queensland through to Victoria with outlying populations on...
(Saw Banksia),
Banksia mediaThe Southern Plains Banksia , also known as Golden Stalk Banksia, is a species of shrub in the plant genus Banksia. It occurs on the south coast of Western Australia between Albany and Israelite Bay, where it is a common plant....
(Southern Plains Banksia) and the
cultivarA cultivar'Cultivar has two meanings as explained under Formal definition. When used in reference to a taxon, the word does not apply to an individual plant but to all those plants sharing the unique characteristics that define the cultivar. is a plant or group of plants selected for desirable...
Banksia 'Giant Candles'Banksia 'Giant Candles is a registered Banksia cultivar. It is a hybrid between the Gosford form of B. ericifolia and a form of B. spinulosa var. cunninghamii....
. Banksia species are primarily propagated by seed in the home garden as cuttings can be difficult to strike. However commercial nurserymen extensively utilize the latter method (indeed, cultivars by nature must be vegetatively propagated by cuttings or grafting).
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. petiolarisBanksia 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...
and
B. 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...
.
Banksias possibly require more TLC (i.e. 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-
phosphorusPhosphorus 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...
fertilizerFertilizer is any organic or inorganic material of natural or synthetic origin that is added to a soil to supply one or more plant nutrients essential to the growth of plants. A recent assessment found that about 40 to 60% of crop yields are attributable to commercial fertilizer use...
should be used, as the proteoid roots may be damaged by high
nutrientA nutrient is a chemical that an organism needs to live and grow or a substance used in an organism's metabolism which must be taken in from its environment. They are used to build and repair tissues, regulate body processes and are converted to and used as energy...
levels in the soil. All respond well to some form of pruning.
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 ASGAP's Banksia Study Group.
Cut flower industry
With the exception of the
nurseryA nursery is a place where plants are propagated and grown to usable size. They include retail nurseries which sell to the general public, wholesale nurseries which sell only to businesses such as other nurseries and to commercial gardeners, and private nurseries which supply the needs of...
industryIndustry refers to the production of an economic good or service within an economy.-Industrial sectors:There are four key industrial economic sectors: the primary sector, largely raw material extraction industries such as mining and farming; the secondary sector, involving refining, construction,...
, Banksia have limited commercial use. Some species, principally
B. coccineaBanksia coccinea, commonly known as the Scarlet Banksia, Waratah Banksia or Albany Banksia, is an erect shrub or small tree in the plant genus Banksia...
(Scarlet Banksia),
B. baxteriThe Baxter's Banksia , also known as Bird's Nest Banksia, is a species of shrub in the plant genus Banksia. It occurs along the south coast of Western Australia between Albany and Esperance....
,
B. hookerianaThe Hooker's Banksia is a species of shrub in the plant genus Banksia. It occurs on sandplain shrubland between Arrowsmith and Eneabba in Western Australia. Seeds do not require any treatment, and take 23 to 49 days to germinate....
(Hooker's Banksia),
B. sceptrumBanksia sceptrum, the Sceptre Banksia, occurs in Western Australia near the central west coast from Geraldton north through Kalbarri to Hamelin Pool. It extends inland almost to Mullewa....
) (Sceptre Banksia),
B. speciosaThe Showy Banksia is a species of large shrub or small tree in the plant genus Banksia. It reaches up to 8 m in height...
(Showy Banksia) and
B. menziesiiBanksia menziesii, commonly known as firewood banksia, is a species of flowering plant in the genus Banksia. It is a gnarled tree up to 10 m tall, or a lower spreading 1–3 m shrub in the more northern parts of its range. The serrated leaves are dull green with new growth a paler grey...
(Menzies' Banksia) are grown on farms in Western and Southern Australia, as well as Israel and Hawaii, and the flower heads harvested for the cut flower trade. Their nectar is also sought by
beekeeperA beekeeper is a person who keeps honey bees for the purposes of securing commodities such as honey, beeswax, pollen, royal jelly; pollinating fruits and vegetables; raising queens and bees for sale to other farmers; and/or for purposes satisfying natural scientific curiosity...
s, not for the quality of the
honeyHoney is a sweet food made by bees using nectar from flowers. The variety produced by honey bees is the one most commonly referred to and is the type of honey collected by beekeepers and consumed by humans...
, which is often poor, but because the trees provide an abundant and reliable source of nectar at times when other sources provide little.
Woodworking
Banksia
woodWood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...
is reddish in color with an attractive grain but it is rarely used as it warps badly on drying. It is occasionally used for ornamental purposes in wood turning and cabinet paneling. It has also been used to make
keelIn boats and ships, keel can refer to either of two parts: a structural element, or a hydrodynamic element. These parts overlap. As the laying down of the keel is the initial step in construction of a ship, in British and American shipbuilding traditions the construction is dated from this event...
s for small
boatA boat is a watercraft of any size designed to float or plane, to provide passage across water. Usually this water will be inland or in protected coastal areas. However, boats such as the whaleboat were designed to be operated from a ship in an offshore environment. In naval terms, a boat is a...
s. Historically, the wood of certain species such as B. serrata was used for yokes and boat parts. The large "cones" or seed pods of B. grandis are used for
woodturningWoodturning is a form of woodworking that is used to create wooden objects on a lathe . Woodturning differs from most other forms of woodworking in that the wood is moving while a stationary tool is used to cut and shape it...
projects. They are also sliced up and sold as drink coasters; these are generally marketed as
souvenirA souvenir , memento, keepsake or token of remembrance is an object a person acquires for the memories the owner associates with it. The term souvenir brings to mind the mass-produced kitsch that is the main commodity of souvenir and gift shops in many tourist traps around the world...
s for international
touristsTourism is travel for recreational, leisure or business purposes. The World Tourism Organization defines tourists as people "traveling to and staying in places outside their usual environment for not more than one consecutive year for leisure, business and other purposes".Tourism has become a...
. Woodturners throughout the world value Banksia pods for making ornamental objects.
Indigenous uses
The
IndigenousIndigenous Australians are the original inhabitants of the Australian continent and nearby islands. The Aboriginal Indigenous Australians migrated from the Indian continent around 75,000 to 100,000 years ago....
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. Banksia trees are a reliable source of insect larvae which are extracted as food.
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 watercolour paintings of every Banksia species by renowned botanical illustrator
A botanical illustrator is a person who paints, sketches or otherwise illustrates botanical subjects such as trees and flowers. The job requires great artistic skill, attention to fine detail, and technical botanical knowledge...
Celia RosserCelia Elizabeth Rosser is a renowned Australian botanical illustrator, best known for having published The Banksias, a three-volume series of monographs containing watercolour paintings of every Banksia species....
, 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 UniversityMonash University is a public university based in Melbourne, Victoria. It was founded in 1958 and is the second oldest university in the state. Monash is a member of Australia's Group of Eight and the ASAIHL....
, the three volumes were published in 1981, 1988 and 2000 respectively.
The Banksia Book
- Begun by Fred Humphries and Charles Gardner, both of whom passed away before its completion, The Banksia Book was eventually completed by Alex George and first published in 1984. A comprehensive volume containing colour illustrations of every species, it is now in its third edition, published in 1996. This book is sought after by many and becoming hard to find.
The Banksia AtlasThe 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...
- In 1983 the Australian Biological Resources Study
Australian Biological Resources Study is a project undertaken by Parks Australia Division of Australia's Department of the Environment, Water, Heritage and the Arts ....
(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 AtlasThe 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...
, which was first published in 1988.
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 GibbsCecilia May Gibbs MBE was an Australian children's author, illustrator, and cartoonist. She is best-known for her gumnut babies , and the book Snugglepot and Cuddlepie....
' children's book
Snugglepot and CuddlepieSnugglepot and Cuddlepie is a series of books written by Australian author May Gibbs. The books chronicle the adventures of the eponymous Snugglepot and Cuddlepie. The central story arc concerns Snugglepot and Cuddlepie and their adventures along with troubles with the villains of the story, the ...
. 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, but
B. attenuataBanksia attenuata, commonly known as the candlestick banksia or slender banksia, is a species of plant in the proteaceae family. Commonly a tree, it reaches 10 m high, but is often a shrub in dryer areas 0.4 to 2 m high...
(Slender Banksia) has also been cited, as this was the species that Gibbs saw as a child in Western Australia.
Other cultural references
In 1989, the
Banksia Environmental FoundationThe Banksia Environmental Foundation is an Australian organisation created in 1989 to support and confer recognition on individuals and organisations that make a positive contribution to the environment. The Foundation launched the annual Banksia Environmental Awards in the same year...
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.
External links