Casuarina is a
genusIn biology, a genus is a taxonomic unit used in the classification of living and fossil organisms. The term comes from Latin genus "descent, family, type, gender" , cognate with – genos, "race, stock, kin" ..In addition, genus is a taxonomic rank in the hierarchy In biology, a genus (plural:...
of 17 species in the family
CasuarinaceaeCasuarinaceae is a family of dicotyledonous flowering plants placed in the order Fagales, consisting of 3 or 4 genera and approximately 70 species of trees and shrubs native to the Old World tropics , Australia, and the Pacific islands...
, native to
AustralasiaAustralasia is a region of Oceania: Australia, New Zealand, the island of New Guinea, and neighbouring islands in the Pacific Ocean. The term was coined by Charles de Brosses in Histoire des navigations aux terres australes . He derived it from the Latin for "south of Asia" and differentiated the...
, southeastern
AsiaAsia is the world's largest and most populous continent, located in the eastern and northern hemispheres. It covers 8.6% of the earth's total surface area and with approximately 4 billion people, it hosts 60% of the world's current human population.Asia is traditionally defined as part of the...
, and islands of the western
Pacific OceanThe Pacific Ocean is the largest of the Earth's oceanic divisions. Its name is derived from the Latin name Tepre Pacificum, "peaceful sea", bestowed upon it by the Portuguese explorer Ferdinand Magellan. It extends from the Arctic in the north to Antarctica in the south, bounded by Asia and...
. It was once treated as the sole genus in the family, but has been split into three genera (see
CasuarinaceaeCasuarinaceae is a family of dicotyledonous flowering plants placed in the order Fagales, consisting of 3 or 4 genera and approximately 70 species of trees and shrubs native to the Old World tropics , Australia, and the Pacific islands...
).
They are
evergreenIn botany, an evergreen plant is a plant having leaves all year round. This contrasts with deciduous plants, which completely lose their foliage for part of the year....
shrubA shrub or bush is a horticultural rather than strictly botanical category of woody plant, distinguished from a tree by its multiple stems and lower height, usually less than 5-6 m tall. A large number of plants can be either shrubs or trees, depending on the growing conditions they experience...
s and
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 growing to 35 m tall. The foliage consists of slender, much-branched green to grey-green twigs bearing minute
scale-leavesIn botany, a leaf is an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin. There is continued debate about whether the flatness of leaves evolved to expose the chloroplasts to more light or to increase the absorption of carbon dioxide. In...
in whorls of 5–20. The
flowerA flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to mediate the union of male sperm with female ovum in order to produce seeds...
s are produced in small
catkinA catkin or ament is a slim, cylindrical flower cluster, with inconspicuous or no petals, usually wind-pollinated but sometimes insect pollinated . They contain many, usually unisexual flowers, arranged closely along a central stem which is often drooping...
-like inflorescences; the male flowers in simple spikes, the female flowers on short peduncles.
Casuarina is a
genusIn biology, a genus is a taxonomic unit used in the classification of living and fossil organisms. The term comes from Latin genus "descent, family, type, gender" , cognate with – genos, "race, stock, kin" ..In addition, genus is a taxonomic rank in the hierarchy In biology, a genus (plural:...
of 17 species in the family
CasuarinaceaeCasuarinaceae is a family of dicotyledonous flowering plants placed in the order Fagales, consisting of 3 or 4 genera and approximately 70 species of trees and shrubs native to the Old World tropics , Australia, and the Pacific islands...
, native to
AustralasiaAustralasia is a region of Oceania: Australia, New Zealand, the island of New Guinea, and neighbouring islands in the Pacific Ocean. The term was coined by Charles de Brosses in Histoire des navigations aux terres australes . He derived it from the Latin for "south of Asia" and differentiated the...
, southeastern
AsiaAsia is the world's largest and most populous continent, located in the eastern and northern hemispheres. It covers 8.6% of the earth's total surface area and with approximately 4 billion people, it hosts 60% of the world's current human population.Asia is traditionally defined as part of the...
, and islands of the western
Pacific OceanThe Pacific Ocean is the largest of the Earth's oceanic divisions. Its name is derived from the Latin name Tepre Pacificum, "peaceful sea", bestowed upon it by the Portuguese explorer Ferdinand Magellan. It extends from the Arctic in the north to Antarctica in the south, bounded by Asia and...
. It was once treated as the sole genus in the family, but has been split into three genera (see
CasuarinaceaeCasuarinaceae is a family of dicotyledonous flowering plants placed in the order Fagales, consisting of 3 or 4 genera and approximately 70 species of trees and shrubs native to the Old World tropics , Australia, and the Pacific islands...
).
They are
evergreenIn botany, an evergreen plant is a plant having leaves all year round. This contrasts with deciduous plants, which completely lose their foliage for part of the year....
shrubA shrub or bush is a horticultural rather than strictly botanical category of woody plant, distinguished from a tree by its multiple stems and lower height, usually less than 5-6 m tall. A large number of plants can be either shrubs or trees, depending on the growing conditions they experience...
s and
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 growing to 35 m tall. The foliage consists of slender, much-branched green to grey-green twigs bearing minute
scale-leavesIn botany, a leaf is an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is typically flat and thin. There is continued debate about whether the flatness of leaves evolved to expose the chloroplasts to more light or to increase the absorption of carbon dioxide. In...
in whorls of 5–20. The
flowerA flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to mediate the union of male sperm with female ovum in order to produce seeds...
s are produced in small
catkinA catkin or ament is a slim, cylindrical flower cluster, with inconspicuous or no petals, usually wind-pollinated but sometimes insect pollinated . They contain many, usually unisexual flowers, arranged closely along a central stem which is often drooping...
-like inflorescences; the male flowers in simple spikes, the female flowers on short peduncles. Most species are
dioeciousPlant sexuality covers the wide variety of sexual reproduction systems found across the plant kingdom. This article describes morphological aspects of sexual reproduction of plants....
, but a few are
monoeciousPlant sexuality covers the wide variety of sexual reproduction systems found across the plant kingdom. This article describes morphological aspects of sexual reproduction of plants....
. The
fruitThe term fruit has different meanings dependent on context, and the term is not synonymous in food preparation and biology. Fruits are the means by which flowering plants disseminate seeds, and the presence of seeds indicates that a structure is most likely a fruit, though not all seeds come from...
is a woody, oval structure superficially resembling a
conifer coneA 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...
made up of numerous
carpelsThe gynoecium is a term with several meanings in botanical usage. In reference to mosses; liverworts; and hornworts, gynoecium refers to a cluster of archegonia and any associated modified leaves or stems present on a gametophyte shoot...
each containing a single seed with a small wing.
Casuarina species are a food source of the
larvaA larva is a young form of animal with indirect development, going through or undergoing metamorphosis ....
e of
hepialidThe Hepialidae is a family of insects in the lepidopteran order. Moths of this family are often referred to as swift moths or ghost moths.-Taxonomy and systematics:...
mothA moth is an insect closely related to the butterfly, both being of the order Lepidoptera. The differences between butterflies and moths are more than just taxonomy. Sometimes the names "Rhopalocera" and "Heterocera" are used to formalize the popular distinction...
s; members of the genus
AenetusAenetus is a genus of moths of the family Hepialidae. There are 24 described species found in Indonesia, New Guinea, New Caledonia, Australia and New Zealand. Most species have green or blue forewings and reddish hindwings but some are predominantly brown or white...
, including
A. lewinii and
A. splendens, burrow horizontally into the trunk then vertically down.
Endoclita malabaricusEndoclita is a genus of moths of the family Hepialidae. There are 60 described species found in eastern and southeast Asia and the Indian subcontinent.- Species :*Endoclyta aboe - India*Endoclyta absurdus - China...
also feeds on
Casuarina. The
noctuidThe Noctuidae or Owlet moths are a family of robustly-built moths that includes more than 35,000 known species out of possibly 100,000 total, in more than 4,200 genera. They constitute the largest family in the Lepidoptera....
Turnip MothThe Turnip Moth is a moth of the family Noctuidae. It is a common European species.This is a very variable species with the forewings ranging from pale buff through to almost black. The paler forms have three dark-bordered stigmata on each forewing...
is also recorded feeding on
Casuarina.
Selected species
- Casuarina cristata Miq. Northeastern Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the continental mainland , the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans...
(QueenslandQueensland is a state of Australia that occupies the north-eastern section of the mainland continent. It is bordered by the Northern Territory to the west, South Australia to the south-west and New South Wales to the south. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...
, New South WalesNew South Wales is Australia's most populous state, located in the south-east of the country, north of Victoria, south of Queensland and east of South Australia...
).
- Casuarina cunninghamiana
Casuarina cunninghamiana - River Oak, River Sheoak, Creek Oak or Fire Oak is a species of Casuarina, native to New South Wales and Queensland, Australia. The River Oak is an attractive evergreen tree with fine greyish green needle-like foliage that grows to a height of 60 metres with a spread...
Miq. Northern and eastern Australia (Northern TerritoriesNorthern Territories may refer to several geographic locations:* Northern Territories, a term used by the Japanese to refer to the territory disputed with Russia...
to New South Wales).
- Casuarina equisetifolia
Casuarina equisetifolia is a species of she-oak of the genus Casuarina, native to Australasia, southeast Asia, and islands of the western Pacific Ocean, from Burma and Vietnam east to French Polynesia, New Caledonia, and Vanuatu, and south to Australia...
L. Northern Australia, southeastern Asia, (MadagascarMadagascar, or Republic of Madagascar , is an island nation in the Indian Ocean off the southeastern coast of Africa. The main island, also called Madagascar, is the fourth-largest island in the world, and is home to 5% of the world's plant and animal species, of which more than 80% are endemic to...
, doubtfully native).
- Casuarina glauca
Casuarina glauca, commonly known as the swamp she-oak, is a species of Casuarina native to the east coast of Australia. It is found from central Queensland south to southern New South Wales. It has become naturalized in the Everglades in Florida where it is considered a weed.-External links:*...
Sieber ex Spreng. New South Wales.
- Casuarina grandis L.A.S.Johnson. New Guinea
New Guinea, located north of Australia, is the world's second largest island. It became separated from the Australian mainland when the area now known as the Torres Strait flooded after the last glacial period. The name Papua has long been associated with the island...
.
- Casuarina junghuhniana Miq. Indonesia
The Republic of Indonesia is a country in Southeast Asia and Oceania. Indonesia comprises 17,508 islands. With an estimated population of around 237 million people, it is the world's fourth most populous country, with the world's largest population of Muslims.Indonesia is a republic, with an...
.
- Casuarina obesa Miq. Southern Australia (southwestern Western Australia, New South Wales [one site, now extinct], Victoria).
- Casuarina oligodon L.A.S.Johnson. New Guinea.
- Casuarina pauper F.Muell. ex L.A.S.Johnson. Interior Australia.
Sources:
Cultivation
Commonly known as the
she-oak,
sheoak,
ironwood, or
beefwood, casuarinas are commonly grown in tropical and subtropical areas throughout the world. The tree has delicate, slender ultimate branches and leaves that are no more than scales, making the tree look more like a wispy conifer. The plants are very tolerant of windswept locations, and are widely planted as wind-breaks, although usually not in agricultural situations.
C. equisetifolia is a common tropical seashore tree known as Common Ironwood, Beefwood, Bull-oak, or Whistling-pine and is often planted as a windbreak. The wood of this tree is used for shingles, fencing, and is said to make excellent, hot burning firewood.
C. oligodon has been planted in New Guinea in an ancient (more than 3,000 years)
silvicultureSilviculture is the art and science of controlling the establishment, growth, composition, health, and quality of forests to meet diverse needs and values of the many landowners, societies and cultures.-Regeneration:...
by highland gardeners practicing an intensive traditional
permaculturePermaculture is an approach to designing human settlements and perennial agricultural systems that mimic the relationships found in natural ecologies. It was first developed by Australians Bill Mollison and David Holmgren and their associates during the 1970s in a series of publications...
. The wood of this tree is used for building-timber, furniture and tools and makes excellent firewood. The tree's root nodules are known to fix nitrogen, and it is traditionally prized for its ability to increase the soil's fertility. Its abundant leaf-fall is high in nitrogen and traditionally prized for mulch.
The gum exuded from some
casuarinas is edible and was a food source for
AboriginalIndigenous Australians are the original inhabitants of the Australian continent and nearby islands, and these peoples' descendants. Indigenous Australians are distinguished as either Aboriginal people or Torres Strait Islanders, who currently together make up about 2.6% of Australia's...
people.
As invasive plants
C. cunninghamiana and
C. equisetifolia have been introduced species in several countries, including
ArgentinaArgentina, officially the Argentine Republic , is the second largest country in South America, constituted as a federation of 23 provinces and an autonomous city, Buenos Aires. It is the eighth largest country in the world by land area and the largest among Spanish-speaking nations, though Mexico,...
,
ChinaMainland China, Continental China, the Chinese mainland or simply the mainland, is a geopolitical term that refers to the area under the jurisdiction of the People's Republic of China , excluding Hong Kong and Macau, which are under the jurisdiction of the PRC but run on different economic and...
,
EgyptEgypt , officially the Arab Republic of Egypt, is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Western Asia...
,
IsraelIsrael officially the State of Israel , is a developed state in Western Asia located on the eastern shore of the Mediterranean Sea. It borders Lebanon in the north, Syria in the northeast, Jordan in the east, and Egypt on the southwest, and contains geographically diverse features within its...
,
IraqIraq , officially the Republic of Iraq , also known as Mesopotamia, is a country in Western Asia spanning most of the northwestern end of the Zagros mountain range, the eastern part of the Syrian Desert and the northern part of the Arabian Desert.Iraq shares borders with Jordan to the west, Syria...
,
KenyaThe Republic of Kenya is a country in East Africa. Lying along the Indian Ocean, at the equator, Kenya is bordered by Ethiopia , Somalia , Tanzania , Uganda plus Lake Victoria , and Sudan . The capital city is Nairobi. Kenya spans an area about 85% the size of France or Texas...
,
MexicoThe United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
,
South AfricaThe Republic of South Africa is a country located at the southern tip of Africa, with a coastline on the Atlantic and Indian Oceans. To the north lie Namibia, Botswana and Zimbabwe, to the east are Mozambique and Swaziland, while Lesotho is an independent country surrounded by South Africa.Modern...
,
the BahamasThe Bahamas, officially the Commonwealth of the Bahamas, is an English-speaking country consisting of 29 islands, 661 cays, and 2,387 rocks. It is located in the Atlantic Ocean north of Cuba, Hispaniola and the Caribbean Sea, northwest of the Turks and Caicos Islands, and southeast of the United...
and the southern
United StatesThe United States of America is a federal constitutional republic comprising fifty states and a federal district...
; in the United States it was introduced in the early 1900s, and is now considered an
invasive species'Invasive species' is a phrase with several definitions. The first definition expresses the phrase in terms of non-indigenous species that adversely affect the habitats they invade economically, environmentally or ecologically...
. The species has nearly quadrupled in southern
FloridaFlorida is a state located in the southeastern region of the United States, bordering Alabama to the northwest and Georgia to the north. It was the 27th state admitted to the United States...
between 1993 and 2005, where it is known as Australian pine.
C. equisetifolia is widespread in the
Hawaiian IslandsThe Hawaiian Islands are an archipelago of 19 islands and atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll. Excluding Midway, which is an unincorporated territory of the...
where it grows both on the seashore in dry, salty, calcareous soils and up in the mountains in high rainfall areas on volcanic soils. It is also an introduced, invasive plant in
BermudaBermuda is a British overseas territory in the North Atlantic Ocean. Located off the east coast of the United States, it is situated around 1,770 kilometres northeast of Miami, Florida, and 1,350 kilometres south of Halifax, Nova Scotia, Canada...
. It was introduced to replace the
Juniperus bermudianaJuniperus bermudiana is a species of juniper endemic to Bermuda. This species is most commonly known as Bermuda cedar although, like most "cedars" it is not a true cedar ; a more botanically accurate name would be Bermuda juniper, but this term is extremely rare.It is an evergreen tree growing up...
windbreaks killed by juniper blight in the 1940s. Now they are growing on cliffs and sandy slopes strangling all surrounding plants, or covering them in needles, they also erode the cliffs by digging their roots deep into them and splitting them apart. The plants are strongly suspected of having
allelopathicAllelopathy is a biological phenomenon that is characteristic of some plants, algae, bacteria, coral and fungi by which they produce certain biochemicals that influence the growth and development of other organisms. The biochemicals, called allelochemicals can have a beneficial or detrimental...
properties, as evidenced by the near absence of understory once a mat of litter develops around the plants.