Silk Tree

There are some 150 species of deciduous, occasionally thorny trees, shrubs, and lianas in this genus, which occurs widely in subtropical regions, from Asia and Africa to Australia, often on poor soils. Albizia julibrissin is a graceful tree that tolerates hot, dry conditions. It is popular as an ornamental, but susceptible to pests and diseases in urban areas. A. julibrissin was first mentioned in Chinese medicine in Omissions for the Materia Medica (Tang Dynasty, c.CE700). Bark of the related A. odoratissima, which bears scented white flowers, is externally used in India and Sri Lanka for ulcers and leprosy.

Smalldomed to flat-topped, spreading tree with smooth, gray-brown bark, and doubly pinnate leaves to 20cm (8in) long. Yellow-green flower heads with very long stamens are borne in terminal clusters, 7-15cm (3-6in) wide in summer.

Common Name:	Silk Tree
Botanical Name:	Albizia julibrissin
Genus:	Albizia
Family:	Mimosaceae
Location:	Iran to Japan
Cultivation:	Well-drained, moisture-retentive soil in full sun. Tolerates poor, alkaline and saline soils, drought, and windy positions. Size and shape may be controlled by cutting back the previous year's growth to 5-6 buds in spring. Plants may be attacked by webworm, scale insects, and nematodes. The trunk may be killed by vascular wilt disease, leaving the roots to sucker. Young specimens make attractive foliage plants and may be treated as annuals for the purpose. Mature specimens are hardier and more floriferous in relatively poor soils, and also in areas with long, hot summers.
Propagation:	By seed sown when ripe, pre-soaked for 12 hours; by semi-ripe cuttings in summer; by root cuttings in spring; by layering in winter.
Harvest:	Bark is removed in spring or late summer, and flowers as they open; both are dried for decoctions.
Height:	6-10m (20-30ft)
:Width	10m (30ft)
Variations:	alba white flowers f. rosea Pink flowers This species tends to be fast-growing but short-lived and can become weedy through suckering and copious production of seedlings.
Hardiness:	Z6-9. The form rosea is a bit hardier than the species.
Parts Used:	Bark, flowers (he huan), leaves
Properties:	A bitter, astringent, sedative herb that is also diuretic and analgesic, with stimulant effects on the circulation, uterus, and appetite (bark); the flowers are tranquilizing and relieve indigestion.
Medicinal Uses:	Internally for insomnia and irritability (bark, flowers), boils and carbuncles (bark), breathlessnessm and poor memory (flowers). Externally for injuries, swellings, and lung abscesses (bark).
Culinary Uses:	Flowers and young leaves are edible. Dried leaves are used for tea.
Bibliography:	Encylopedia of Herbs by Deni Brown Copyright ©: 1995, 2001 Dorling Kindersley Limited pg 109