Ailanthus
Encyclopedia
Ailanthus is a genus of tree
s belonging to the family Simaroubaceae
, in the order Sapindales
(formerly Rutales or Geraniales
). The genus is native from east Asia
south to northern Australasia
.
They are fast-growing deciduous
trees growing to 25–45 m tall, with spreading branches and large (40–100 cm) pinnate leaves with 15-41 long pointed leaflets, the terminal leaflet normally present, and the basal pairs of leaflets often lobed at their bases. The small yellow to greenish flower
s are borne on branched panicles. They turn reddish later in the year and eventually brown. They stay on the tree for a long time; the male flowers have a strong odour. The odour tends to resemble the smell of strong cat urine or the spray of a male cat. Also, touching the leaves leaves an unpleasant smell on the hands. The fruit
is a samara
drawn out into a long wing with the seed in the middle. The wood is fine grained and satiny.
This genus is considered invasive
in North America and Britain. It sends out suckers that can damage pavements and walls, and in the right conditions it can spread very quickly.
It has the capacity to get to large heights and can outcompete native plant species around it.
Ailanthus are capable of forming thick blankets of roots and heavy shade to the extent that native species are prevented from being able to reclaim an area that has been logged or deforested, as well as areas that have been heavily developed.
A silk spinning moth, the Ailanthus silkmoth (Samia cynthia), lives on Ailanthus leaves, and yields a silk more durable and cheaper than mulberry silk, but inferior to it in fineness and gloss. This moth has been introduced to the eastern United States and is common near many towns; it is about 12 cm across, with angulated wings, and in colour olive brown, with white markings. Other Lepidoptera
whose larva
e feed on Ailanthus include Endoclita malabaricus
.
Tree
A 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 belonging to the family Simaroubaceae
Simaroubaceae
The Simaroubaceae is a small, mostly tropical, family in the order Sapindales. In recent decades it has been subject to much taxonomic debate, with several small families being split off...
, in the order Sapindales
Sapindales
Sapindales is a botanical name for an order of flowering plants. Well-known members of Sapindales include citrus; maples, horse-chestnuts, lychees and rambutans; mangos and cashews; frankincense and myrrh; mahogany and neem....
(formerly Rutales or Geraniales
Geraniales
Geraniales are a small order of flowering plants, included within the rosid subgroup of dicotyledons. The largest family in the order is Geraniaceae with over 800 species. In addition, the order includes some small families, contributing together another less than 40 species...
). The genus is native from east Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
south to northern Australasia
Australasia
Australasia is a region of Oceania comprising 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...
.
They are fast-growing deciduous
Deciduous
Deciduous means "falling off at maturity" or "tending to fall off", and is typically used in reference to trees or shrubs that lose their leaves seasonally, and to the shedding of other plant structures such as petals after flowering or fruit when ripe...
trees growing to 25–45 m tall, with spreading branches and large (40–100 cm) pinnate leaves with 15-41 long pointed leaflets, the terminal leaflet normally present, and the basal pairs of leaflets often lobed at their bases. The small yellow to greenish flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s are borne on branched panicles. They turn reddish later in the year and eventually brown. They stay on the tree for a long time; the male flowers have a strong odour. The odour tends to resemble the smell of strong cat urine or the spray of a male cat. Also, touching the leaves leaves an unpleasant smell on the hands. The fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
is a samara
Samara (fruit)
A samara is a type of fruit in which a flattened wing of fibrous, papery tissue develops from the ovary wall. A samara is a simple dry fruit and indehiscent . It is a winged achene...
drawn out into a long wing with the seed in the middle. The wood is fine grained and satiny.
Species
The number of species is disputed, with some authorities accepting up to ten species, while others accept six or fewer. Species include:- Ailanthus altissima (Tree of Heaven) – northern and central mainland ChinaMainland ChinaMainland 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 . According to the Taipei-based Mainland Affairs Council, the term excludes the PRC Special Administrative Regions of Hong Kong and...
, TaiwanTaiwanTaiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...
, arguably the best known species. Ailanthus vilmorinianaAilanthus vilmorinianaAilanthus vilmoriniana, commonly known as Downy Tree of Heaven, is a tree in the quassia family. It is native to western China, but is occasionally encountered in northern European gardens.-Description:...
is a synonym of Ailanthus altissima. - Ailanthus excelsa – IndiaIndiaIndia , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
and Sri LankaSri LankaSri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the... - Ailanthus integrifoliaAilanthus integrifoliaAilanthus triphysa is also known as White Siris Ailanthus integrifolia is a species of plant in the Simaroubaceae family. It is found in India, Indonesia, Malaysia, Papua New Guinea, the Solomon Islands, and Vietnam....
– New GuineaNew 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 QueenslandQueenslandQueensland 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...
, AustraliaAustraliaAustralia , 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... - Ailanthus triphysaAilanthus triphysaAilanthus triphysa is an Asian and Australian rainforest tree.-Distribution:It occurs in India, Sri Lanka, China, Malaysia, Burma, Thailand, Laos, Philippines, Indonesia and Vietnam...
(White Siris) – northern and eastern Australia. Ailanthus malabarica is a synonym of Ailanthus triphysa.
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
in North America and Britain. It sends out suckers that can damage pavements and walls, and in the right conditions it can spread very quickly.
It has the capacity to get to large heights and can outcompete native plant species around it.
Ailanthus are capable of forming thick blankets of roots and heavy shade to the extent that native species are prevented from being able to reclaim an area that has been logged or deforested, as well as areas that have been heavily developed.
A silk spinning moth, the Ailanthus silkmoth (Samia cynthia), lives on Ailanthus leaves, and yields a silk more durable and cheaper than mulberry silk, but inferior to it in fineness and gloss. This moth has been introduced to the eastern United States and is common near many towns; it is about 12 cm across, with angulated wings, and in colour olive brown, with white markings. Other Lepidoptera
Lepidoptera
Lepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...
whose larva
Larva
A 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 feed on Ailanthus include Endoclita malabaricus
Endoclita
Endoclita 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 :*E. aboe - India*E. absurdus - China*E. actinidae - China...
.