''Albizia julibrissin'', the Persian silk tree, pink silk tree, or mimosa tree, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriat ...

of tree in the family Fabaceae,

native Native may refer to: People * Jus soli, citizenship by right of birth * Indigenous peoples, peoples with a set of specific rights based on their historical ties to a particular territory ** Native Americans (disambiguation) In arts and entert ...

southwestern Asia Western Asia, West Asia, or Southwest Asia, is the westernmost subregion of the larger geographical region of Asia, as defined by some academics, UN bodies and other institutions. It is almost entirely a part of the Middle East, and includes ...

and eastern Asia. The genus is named after the Italian nobleman Filippo degli Albizzi, who introduced it to Europe in the mid-18th century. It is sometimes incorrectly spelled ''Albizzia''. The specific epithet ''julibrissin'' is a corruption of the Persian word (), which means "

silk flower Artificial plants are imitations of natural plants used for commercial or residential decoration. They are sometimes made for scientific purposes (the collection of Glass Flowers, glass flowers at Harvard University, for example, illustrates t ...

" (from "flower" + " silk"). ''Albizia julibrissin'' was described by Antonio Durazzini. John Gilbert Baker used the same scientific name to refer to Prain's '' Albizia kalkora'', the ''Mimosa kalkora'' of William Roxburgh.

Names

''Albizia julibrissin'' is known by a wide variety of common names, such as Persian silk tree and pink siris. It is also called

Lankaran Lankaran ( az, Lənkəran, ) is a city in Azerbaijan, on the coast of the Caspian Sea, near the southern border with Iran. As of 2021, the city had a population of 89,300. It is next to, but independent of, Lankaran District. The city forms a di ...

acacia or bastard tamarind, though it is not too closely related to either genus. The species is called Chinese silk tree, silk tree or mimosa in the United States, which is misleading—the former can refer to any species of '' Albizia'' which is most common in any one locale; and, although once included in '' Mimosa'', neither is it very close to the Mimoseae. To add to the confusion, several species of '' Acacia'', notably '' Acacia baileyana'' and '' Acacia dealbata'', are also known as "mimosa" (especially in floristry), and many Fabaceae trees with highly divided leaves are called thus in horticulture. Jungpflanze des Seidenbaums (Schlafbaum)

Jungpflanze des Seidenbaums (Schlafbaum)

Its leaves slowly close during the night and during periods of rain, the leaflets bowing downward; thus its modern Persian name () means "night sleeper". This tendency also explains the Chinese common name hehuan, which means "shut happy" and symbolizes a happy couple in bed. In Japan its common names are , and which all mean "sleeping tree". Nemu tree is a partial translation of .

Description

''Albizia julibrissin'' is a small deciduous tree with a broad crown of level or arching branches, growing to tall. Its

bark Bark may refer to: * Bark (botany), an outer layer of a woody plant such as a tree or stick * Bark (sound), a vocalization of some animals (which is commonly the dog) Places * Bark, Germany * Bark, Warmian-Masurian Voivodeship, Poland Arts, e ...

is dark greenish grey, becoming vertically striped with age. Its leaves are large and frond-like: They are bipinnate, divided into 6–12 pairs of pinnae, each with 20–30 pairs of leaflets. Individual leaflets are oblong, long and broad. The true leaves are long and broad.

The flowers bloom throughout the summer in dense inflorescences, which resemble starbursts of pink silky threads. The true flowers have small

calyx Calyx or calyce (plural "calyces"), from the Latin ''calix'' which itself comes from the Ancient Greek ''κάλυξ'' (''kálux'') meaning "husk" or "pod", may refer to: Biology * Calyx (anatomy), collective name for several cup-like structures ...

and

corolla Corolla may refer to: *Corolla (botany), the petals of a flower, considered as a unit *Toyota Corolla, an automobile model name *Corolla (headgear) A ''corolla'' is an ancient headdress in the form of a small circlet or crown.stamens, 2–3 cm long and white or pink with a white base. They have been observed to attract

bee Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfami ...

s, butterflies and hummingbirds. Its fruit is a flat brown pod long and broad, containing several seeds inside. There are two varieties: * ''Albizia julibrissin'' var. ''julibrissin'' – the typical variety, described above * ''Albizia julibrissin'' var. ''mollis'' – differs in the shoots being densely hairy

Habitat, cultivation and uses

Original habitats of the tree include regions from Iran (Persia) and the Republic of Azerbaijan to

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slig ...

and Korea. ''A. julibrissin'' is widely planted as an ornamental plant in parks and gardens, grown for its fine leaf texture, flowers and attractive horizontal canopy. Other positive attributes are a fast growth rate, low water requirements and the ability to thrive planted in full sun in hot summer climates. It is frequently planted in semi-arid areas like California's Central Valley, central Texas and Oklahoma. Although capable of surviving drought, growth will be stunted and the tree tends to look sickly. As such it should be given infrequent, deep waterings during the summer, which will benefit growth and flowering. The broad crown of a mature tree makes it useful for providing dappled shade. The flower colour varies from white in ''A. julibrissin'' f. ''alba'', to rich red-tipped flowers. Variants with cream or pale yellow flowers are also reported. Other cultivars are becoming available: 'Summer Chocolate' has red foliage ageing to dark bronze, with pale pink flowers; 'Ishii Weeping' (or 'Pendula') has a drooping growth habit.

''A. julibrissin'' f. ''rosea''

There is also a

form Form is the shape, visual appearance, or configuration of an object. In a wider sense, the form is the way something happens. Form also refers to: *Form (document), a document (printed or electronic) with spaces in which to write or enter data * ...

, ''A. julibrissin'' f. ''rosea'' (pink silk tree) which has, in the past, been classed either as a variety or as a cultivar. This is a smaller tree, only growing to tall, with the flowers always pink. Native to the northeast of the species' range in Korea and Northern China, it is more cold-tolerant than the typical form, surviving temperatures down to at least . The selected cultivar ''A. julibrissin'' 'Ernest Wilson' (also known as 'E.H.Wilson' or 'Rosea') is a cold-tolerant tree with deep pink flower colour. In Japan, ''A. julibrissin'' f. ''rosea'' is often used for non-traditional bonsai. The name (, Kanji: ) and its variants is a '' kigo'' representing the summer in haiku, especially a sleepy summer evening. ''A. julibrissin'' f. ''rosea'' has gained the Royal Horticultural Society's Award of Garden Merit; likewise the cultivar 'Summer Chocolate'.

Other uses

The sweet-scented flowers are a good nectar source for honeybees and butterflies. In Central America, the thornbug ('' Umbonia spinosa'') prefer its branches for mating and overwintering. There is conflicting information on the toxicity of pods and seeds to humans and animals; some parts of the plant may contain neurotoxin. Silk tree wood may be used to make furniture. Pink silk tree can be used to treat the effects of stinging nettle (''Urtica dioica'') by rubbing the leaves in hand and then applying to the rash area. Relief is almost instantaneous.

Invasive species

In the wild, the tree tends to grow in dry plains, sandy valleys, and uplands. It has become an invasive species in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

, where it has spread from southern New York, New Jersey and Connecticut, west to Missouri and Illinois, and south to Florida and Texas. It is cultivated in California and Oregon. Its seeds are wind-dispersed and numerous, and they are fertile even over long periods of drought. Each pod, which resembles a flattened bean pod made of paper, holds about 8 seeds on average. The pod bursts in strong winds, and the seeds can carry over surprisingly long distances. Breeding work is currently underway in the United States to produce ornamental plants which will not set seed and can be planted without risk. However, in the eastern United States it is generally a short-lived tree, being highly susceptible to mimosa vascular wilt,Fusarium Wilt of Mimosa (''Albizia julibrissin'')
Virginia Cooperative Extension a fungal disease caused by a species of ''

Fusarium ''Fusarium'' is a large genus of filamentous fungi, part of a group often referred to as hyphomycetes, widely distributed in soil and associated with plants. Most species are harmless saprobes, and are relatively abundant members of the soil mi ...

'', though the disease does not seem to have seriously impacted its populations. Because of its invasive tendencies and disease susceptibility, it is rarely recommended as an ornamental plant in the United States, though it is still widely planted in parts of Europe.

References

External links

''Albizia julibrissin'' List of Chemicals (Dr. Duke's Databases)
{{taxonbar, from=Q750307 julibrissin Fodder Naturalized trees of Alabama Trees of Europe Plants used in traditional Chinese medicine Trees of Korea