''Brachychiton'' (kurrajong, bottletree) is a
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
of 31
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of
tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, e.g., including only woody plants with secondary growth, only ...
s and large
shrub
A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...
s, native to
Australia
Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
(the
centre of diversity
A Vavilov center or center of origin is a geographical area where a group of organisms, either domesticated or wild, first developed its distinctive properties. Centers of origin were first identified in 1924 by Nikolai Vavilov. Vavilov posit ...
, with 30 species) and
New Guinea
New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...
(one species). Fossils from
New South Wales
New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...
and New Zealand are estimated to be 50 million years old, corresponding to the
Paleogene
The Paleogene Period ( ; also spelled Palaeogene or Palæogene) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period Ma (million years ago) to the beginning of the Neogene Period Ma. It is the fir ...
.
Description
They grow to 4 – 30m tall, and some are dry-season
deciduous
In the fields of horticulture and botany, the term deciduous () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed Leaf, leaves, usually in the autumn; to the shedding of petals, aft ...
. Several species (though not all) are
pachycaul plants with a very stout stem for their overall size, used to store water during periods of
drought
A drought is a period of drier-than-normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, ...
. The
leaves
A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...
show intraspecific variation and generally range from entire to deeply palmately lobed with long slender leaflet-like lobes joined only right at the base. Their sizes range from 4 – 20 cm long and wide.
All species are
monoecious
Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system comparable with gynomonoecy, andromonoecy and trimonoecy, and contras ...
with separate male and female flowers on the same plant. The flowers have a bell-shaped
perianth
The perianth (perigonium, perigon or perigone in monocots) is the non-reproductive part of the flower. It is a structure that forms an envelope surrounding the sexual organs, consisting of the calyx (sepals) and the corolla (petals) or tepal ...
consisting of a single series of fused lobes which is regarded as a
calyx despite being brightly coloured in most species. The female flowers have five separate
carpels
Gynoecium (; ; : gynoecia) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ...
that can each form a woody fruit containing several seeds. The flower colour is often variable within species. Eastern forest species drop their foliage before flowering but those of the drier regions carry the flowers while in leaf.
Name
The name ''Brachychiton'' is derived from the
Greek
Greek may refer to:
Anything of, from, or related to Greece, a country in Southern Europe:
*Greeks, an ethnic group
*Greek language, a branch of the Indo-European language family
**Proto-Greek language, the assumed last common ancestor of all kno ...
''brachys'', short, and ''
chiton
Chitons () are marine molluscs of varying size in the class Polyplacophora ( ), formerly known as Amphineura. About 940 extant and 430 fossil species are recognized.
They are also sometimes known as sea cradles or coat-of-mail shells or suck ...
'',
tunic
A tunic is a garment for the torso, usually simple in style, reaching from the shoulders to a length somewhere between the hips and the ankles. It might have arm-sleeves, either short or full-length. Most forms have no fastenings. The name deri ...
, in referring to its loose
seed
In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...
coats. The generic name is often misconstrued as being of neuter gender, with the specific epithets then incorrectly amended. Thus ''B. rupestre'' and ''B. populneum'' are sometimes seen in horticultural books and magazines.
''Kurrajong'' comes from the
Dharuk language ''garrajuŋ'' 'fishing line', as fishing lines were made from kurrajong bark.
Species

33 species are accepted.
[
]
Cultivation
A few species of Kurrajong are popular garden trees and have been introduced to hot dry regions including the Mediterranean, South Africa and the western United States. These species are also hybridised for horticultural purposes, ''B. populneo-acerifolius'' being one example. Kurrajongs are known to bloom erratically in cultivation.
References
Further reading
*
*Macoboy, S. (1991) What tree is that?,
*Rathie, Kerry (2014) Brachychitons: Flame Trees, Kurrajongs and Bottle Trees
External links
Notes on Fossil Leaves, Stewart R. Hinsley, 2005
* PlantListbr>search for Brachychiton
Retrieved 20190318.
{{Authority control
Malvaceae genera
Flora of the Australasian realm
Taxa described in 1832
Taxa named by Heinrich Wilhelm Schott
Taxa named by Stephan Endlicher