Xanthorrhoea
Encyclopedia
Xanthorrhoea is a genus
of flowering plant
s native to Australia
and a member of family
Xanthorrhoeaceae
, being the only member of subfamily Xanthorrhoeoideae. The Xanthorrhoeaceae are monocots, part of order Asparagales
. There are 28 species
and five subspecies of Xanthorrhoea.
All are perennials
and have a secondary thickening meristem in the stem. Many, but not all, species develop an above ground stem. This is rough-surfaced, built from accumulated leaf-bases around the secondarily thickened trunk. The trunk is sometimes unbranched, some species will branch if the growing point is damaged and others naturally grow numerous branches. Flowers are borne on a long spike above a bare section called a scape, the total length can be up to four metres long in some species. Flowering occurs in a distinct flowering period, which varies for each species. Flowering can be stimulated by bushfire, in which case it occurs in the next flowering period after the fire.
are established plants taken from bushland. Nurseries charge high prices for the plants. However, there is a very low survival rate for nursery purchased plants, which may take 3–4 years to die. The most successful examples of transplanting have been where a substantial amount of soil (> 1 cubic metre) has been taken with the plants.
name balga is used for X. preissii
. In South Australia
, Xanthorrhoea is commonly known as yakka
, also spelled yacca and yacka, a name probably from a South Australian Aboriginal language, mostly likely Kaurna.
. In the bush the flowers are used as a compass. This is because flowers on the warmer, sunnier side of the spike (usually the north facing side) often open before the flowers on the cooler side facing away from the sun.
The resin from Xanthorrhoea plants is used in spear
-making and is an invaluable adhesive for Aboriginal people, often used to patch up leaky coolamon
s (water-containers) and even yidaki (didgeridoos).
and Dasypogon
are unrelated Australian plants with a similar growth habit to Xanthorrhoea. Both genera have at times been confused with xanthorrhoeas and mis-named as grasstrees. Some plant classification systems such as Cronquist have included a wide range of other genera in the same family as Xanthorrhoea. However, later anatomical and phylogenetic research has supported the view of Dahlgren who regarded Xanthorrhoea as the sole member of his family Xanthorrhoeaceae sensu stricto, which is now treated as the subfamily Xanthorrhoeoideae of a much more broadly defined family Xanthorrhoeaceae.
According to the World Checklist of Selected Plant Families, there are 28 species in the genus:
Genus
In 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 flowering plant
Flowering plant
The flowering plants , also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants. Angiosperms are seed-producing plants like the gymnosperms and can be distinguished from the gymnosperms by a series of synapomorphies...
s native to Australia
Australia
Australia , 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...
and a member of family
Family (biology)
In 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...
Xanthorrhoeaceae
Xanthorrhoeaceae
Xanthorrhoeaceae is the botanical name of a family of flowering plants in the order Asparagales. Such a family has been recognized by most taxonomists, but the circumscription of the family has varied wildly....
, being the only member of subfamily Xanthorrhoeoideae. The Xanthorrhoeaceae are monocots, part of order Asparagales
Asparagales
Asparagales is the name of an order of plants, used in modern classification systems such as the APG III system . The order takes its name from the family Asparagaceae and is placed in the monocots. The order has only recently been recognized in classification systems...
. There are 28 species
Species
In 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...
and five subspecies of Xanthorrhoea.
Description
Perennial plant
A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...
and have a secondary thickening meristem in the stem. Many, but not all, species develop an above ground stem. This is rough-surfaced, built from accumulated leaf-bases around the secondarily thickened trunk. The trunk is sometimes unbranched, some species will branch if the growing point is damaged and others naturally grow numerous branches. Flowers are borne on a long spike above a bare section called a scape, the total length can be up to four metres long in some species. Flowering occurs in a distinct flowering period, which varies for each species. Flowering can be stimulated by bushfire, in which case it occurs in the next flowering period after the fire.
Growth rates
There is no doubt that Xanthorrhoea grow very slowly. However, this is often generalized to mean they all grow at the rate of about an inch (2½ cm) per year. In actuality, after the initial establishment phase, the rate of growth varies widely from species to species. Thus, while a five-metre tall member of the fastest growing Xanthorrhoea may be 200 years old, a member of a more slowly-growing species of equal height may have aged to 600 years.Cultivation
Xanthorrhoea may be cultivated, as seed is easily collected and germinated. While they do grow slowly, quite attractive plants with short trunks (10 cm) and leaf crowns up to 1.5 m (to the top of the leaves) can be achieved in 10 years. The slow growth rate means that it can take 30 years to achieve a specimen with a significant trunk. Most Xanthorrhoea sold in nurseriesNursery (horticulture)
A 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...
are established plants taken from bushland. Nurseries charge high prices for the plants. However, there is a very low survival rate for nursery purchased plants, which may take 3–4 years to die. The most successful examples of transplanting have been where a substantial amount of soil (> 1 cubic metre) has been taken with the plants.
Common names
The best known common name for the Xanthorrhoea is blackboy. This name refers to the purported similarity in appearance of the trunked species to an Aboriginal boy holding an upright spear. Some people now consider this name to be offensive, or at least belonging to the past, preferring instead grasstree. In the South West, the NoongarNoongar
The Noongar are an indigenous Australian people who live in the south-west corner of Western Australia from Geraldton on the west coast to Esperance on the south coast...
name balga is used for X. preissii
Xanthorrhoea preissii
Xanthorrhoea preissii , with the common name Balga, is a widespread species of perennial monocot in Southwest Australia. This plant, and other members of the genus Xanthorrhoea, are also known as grasstrees...
. In South Australia
South Australia
South Australia is a state of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.South Australia shares borders with all of the mainland...
, Xanthorrhoea is commonly known as yakka
Yakka
Yakka may refer to:* Yakka Banovic , Bosnian footballer* A Lot of Hard Yakka, autobiography by English cricketer journalist Simon Hughes* Yacka, South Australia, settlement in South Australia...
, also spelled yacca and yacka, a name probably from a South Australian Aboriginal language, mostly likely Kaurna.
Traditional Aboriginal uses
Xanthorrhoea is important to the Aboriginal people who live where it grows. The flowering spike makes the perfect fishing spear. It is also soaked in water and the nectar from the flowers gives a sweet tasting drinkAustralian Aboriginal sweet foods
Australian Aborigines had many ways to source sweet foods. The four main types of sweet foods gathered – apart from ripe fruit – were:* honey from ants and bees * leaf scale * tree sap* flower nectar...
. In the bush the flowers are used as a compass. This is because flowers on the warmer, sunnier side of the spike (usually the north facing side) often open before the flowers on the cooler side facing away from the sun.
The resin from Xanthorrhoea plants is used in spear
Spear
A spear is a pole weapon consisting of a shaft, usually of wood, with a pointed head.The head may be simply the sharpened end of the shaft itself, as is the case with bamboo spears, or it may be made of a more durable material fastened to the shaft, such as flint, obsidian, iron, steel or...
-making and is an invaluable adhesive for Aboriginal people, often used to patch up leaky coolamon
Coolamon (vessel)
A coolamon is an Indigenous Australian carrying vessel.It is a multi-purpose shallow vessel, or dish with curved sides, ranging in length from 30–70 cm, and similar in shape to a canoe....
s (water-containers) and even yidaki (didgeridoos).
Similar plants
KingiaKingia
Kingia is a genus of the plant family Dasypogonaceae, consisting of a single species Kingia australis. It has a thick pseudo-trunk consisting of accumulated leaf-bases, with a cluster of long, slender leaves on top. The trunk is usually unbranched, but can branch if the growing tip is damaged...
and Dasypogon
Dasypogon
Dasypogon is a genus of flowering plants in the family Dasypogonaceae. It includes three species....
are unrelated Australian plants with a similar growth habit to Xanthorrhoea. Both genera have at times been confused with xanthorrhoeas and mis-named as grasstrees. Some plant classification systems such as Cronquist have included a wide range of other genera in the same family as Xanthorrhoea. However, later anatomical and phylogenetic research has supported the view of Dahlgren who regarded Xanthorrhoea as the sole member of his family Xanthorrhoeaceae sensu stricto, which is now treated as the subfamily Xanthorrhoeoideae of a much more broadly defined family Xanthorrhoeaceae.
Species
- Xanthorrhoea acanthostachya D.J.Bedford
- Xanthorrhoea acaulis (A.T.Lee) D.J.Bedford
- Xanthorrhoea arboreaXanthorrhoea arboreaXanthorrhoea arborea a species of grasstree of the genus Xanthorrhoea native to New South Wales and Queensland. It was one of the many species authored by the Scottish botanist Robert Brown....
R.Br. - Xanthorrhoea arenaria D.J.Bedford
- Xanthorrhoea australisXanthorrhoea australisXanthorrhoea australis, the Grass-tree or Black Boy is a unique Australian plant. It is the most commonly seen species of the genus Xanthorrhoea . Its fire-blackened trunk can grow up to several metres tall and is often branched...
R.Br. - Xanthorrhoea bracteata R.Br.
- Xanthorrhoea brevistyla D.A.Herb.
- Xanthorrhoea brunonis Endl. in J.G.C.Lehmann
- Xanthorrhoea caespitosa D.J.Bedford
- Xanthorrhoea concava (A.T.Lee) D.J.Bedford
- Xanthorrhoea drummondii Harv.
- Xanthorrhoea fulvaXanthorrhoea fulvaXanthorrhoea fulva a species of grasstree of the genus Xanthorrhoea native to New South Wales and Queensland. It was previously regarded as a subspecies of Xanthorrhoea resinosa, but reclassified as a species in its own right in 1986....
(A.T.Lee) D.J.Bedford - Xanthorrhoea glaucaXanthorrhoea glaucaXanthorrhoea glauca, known as the Grass Tree, is a large plant in the genus Xanthorrhoea, widespread in eastern Australia. The trunk can grow in excess of 5 metres tall, and may be many branched. It is occasionally seen in large communities in nutrient rich soils...
D.J.Bedford - Xanthorrhoea gracilis Endl. in J.G.C.Lehmann
- Xanthorrhoea johnsoniiXanthorrhoea johnsoniiXanthorrhoea johnsonii, known as the Grass Tree, or Johnsons Grass Tree is a large plant in the genus Xanthorrhoea. Found in eastern Australia. The trunk can grow to 5 metres tall....
A.T.Lee - Xanthorrhoea latifolia (A.T.Lee) D.J.Bedford
- Xanthorrhoea macronemaXanthorrhoea macronemaXanthorrhoea macronema, is a forest plant in the genus Xanthorrhoea. Found in eastern Australia north of Sydney, in coastal regions. The trunk of this Grass Tree is underground....
F.Muell. ex Benth. - Xanthorrhoea malacophylla D.J.Bedford
- Xanthorrhoea mediaXanthorrhoea mediaXanthorrhoea media, known as a Grass Tree, or Gulgadya in the Cadigal language, is a mid-sized plant in the genus Xanthorrhoea. The specific epithet media is from the Latin, and refers to the fact that this species is in the middle of the taxonomic range for this group.This perennial shrub is...
R.Br. - Xanthorrhoea minorXanthorrhoea minorXanthorrhoea minor is a species of grasstree of the genus Xanthorrhoea native to south-eastern Australia. It was one of the many species authored by the Scottish botanist Robert Brown....
R.Br. - Xanthorrhoea nana D.A.Herb.
- Xanthorrhoea platyphylla D.J.Bedford
- Xanthorrhoea preissiiXanthorrhoea preissiiXanthorrhoea preissii , with the common name Balga, is a widespread species of perennial monocot in Southwest Australia. This plant, and other members of the genus Xanthorrhoea, are also known as grasstrees...
Endl. in J.G.C.Lehmann (syn. Xanthorrhoea pecoris F.Muell., Xanthorrhoea reflexa Endl.) - Xanthorrhoea pumilio R.Br.
- Xanthorrhoea quadrangulataXanthorrhoea quadrangulataXanthorrhoea quadrangulata is a plant in the genus Xanthorrhoea....
F.Muell. - Xanthorrhoea resinosaXanthorrhoea resinosaXanthorrhoea resinosa , is known as one of the Grass Trees, a mid-sized plant in the genus Xanthorrhoea. The specific epithet is from the Latin, meaning “having resin”...
Pers. (syn. Xanthorrhoea hastilis Pers., Xanthorrhoea resinifera (Sol. ex Kite) E.C.Nelson & D.J.Bedford, nom. inval.) - Xanthorrhoea semiplana F.Muell.
- Xanthorrhoea thorntonii Tate
External links
- Xanthorrhoea australis - R.Br. Plants For A Future
- XANTHORRHOEA INFORMATION PAGE Monica Pawlan
- Xanthorrhoea, Australian Plant Name Index (APNI)