Ailanthus
From Wikipedia, the free encyclopedia
| iAilanthus | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
 Ailanthus altissima leaf and seeds
|
||||||||||||
| Scientific classification | ||||||||||||
|
||||||||||||
|
|
||||||||||||
|
See text |
Ailanthus (derived from ailanto, an Ambonese word probably meaning "tree of the gods" or "tree of heaven") is a genus of trees 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 and evergreen 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 flowers are borne on branched panicles; the male flowers have a strong odour. The fruit is a samara drawn out into a long wing with the seed in the middle. The wood is fine grained and satiny.
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 China, Taiwan
- Ailanthus excelsa – India and Sri Lanka
- Ailanthus integrifolia – New Guinea and Queensland, Australia
- Ailanthus malabarica – southeast Asia
- Ailanthus triphysa (White Siris) – northern and eastern Australia
- Ailanthus vilmoriniana (Downy Tree of Heaven) – southwest China
The best known species, A. altissima, is a native of northern and central China, and an invasive species widely elsewhere. In southwest China it is replaced by A. vilmoriniana, which differs in pubescent (downy) leaves, and in soft spines on shoots on young trees; some botanists do not regard it as distinct from A. altissima.
A silk spinning moth, the Ailanthus moth (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 larvae feed on Ailanthus include Endoclita malabaricus.
