Albizia

Albizia is a genus of flowering plants in the legume family Fabaceae, consisting of around 60 to 80 described species of trees and shrubs native to tropical and subtropical regions of Africa, Asia, the Americas, and Oceania. Members of this genus are commonly known as albizias, and several species are grown ornamentally for their rapid growth and showy inflorescences.

They typically have bipinnate leaves with numerous small leaflets; in many species the leaves close at night. The flowers are arranged in dense, ball- or bottlebrush-like inflorescences, and are usually pink, purplish, or cream-colored, with long prominent stamens. Fruits are flat, woody pods containing several seeds.

Albizia species are fast-growing, drought-tolerant, and capable of fixing atmospheric nitrogen through symbiosis with rhizobia, which can improve soil fertility. They are widely used in reforestation, agroforestry, shade planting, and erosion control.

Some species have become naturalized or invasive outside their native range; the Persian silk tree (Albizia julibrissin) has become invasive in parts of the United States, where it can form dense stands and outcompete native vegetation.

Notable species include Albizia julibrissin (Persian silk tree), Albizia saman (rain tree), and Albizia lebbeck (lebbeck or Indian siris), which are valued for ornament, shade, and timber applications. Albizia is also used in agroforestry systems to improve soil conditions and provide rapid biomass.