Changes

:Chromosome number: ''x''= 13;''A. chinensis'',''A. lebbeck'',''A. lebbekoides'',''A. procera'': 2''n''= 26

*Evergreen to briefly deciduous shrubs or small to fairly large trees up to 35(-50) m tall, rarely armed lianas; bole straight or rather crooked, short or branchless for up to 20 m, up to 100(-150) cm in diameter, sometimes with small buttresses; bark surface smooth to closely fissured, lenticellate, grey to blackish, inner bark coarsely fibrous, reddish-brown or yellow to cream; crown usually flattened. *Leaves arranged spirally, bipinnate, rachis and pinnae with extrafloral nectaries; leaflets many, opposite, entire; stipules caducous. *Flowers in pedunculate glomerules or corymbs which are axillary or aggregated into a terminal or axillary panicle, 5-merous, often dimorphic, the marginal flowers in each head bisexual, the central ones male; calyx and corolla connate, valvate; stamens many, united into a tube below, long exserted; ovary superior, 1-locular with many ovules, style filiform. *Fruit a straight, flat, dehiscent to indehiscent pod. *Seed circular to ellipsoid, more or less flattened, the hard testa with pleurogram. *Seedling with epigeal germination; cotyledons emergent, fleshy; hypocotyl elongated; first 2 leaves opposite or subopposite, subsequent ones arranged spirally, initially pinnate or bipinnate from the start.

''Albizia'' belongs to the subfamily ''Mimosoideae'' and the tribe ''Ingeae'' , together with e.g. the genera ''Archidendron'' and ''Paraserianthes'' . The distinction between the various genera is difficult, and has given rise to a complicated nomenclatural history. ''Albizia'' is often misspelled as ''Albizzia'' , ''A. lebbekoides'' often as ''A. lebbeckioides'' .

''Albizia'' is usually found scattered or in small groups as a pioneer in open, secondary vegetation or primary deciduous or monsoon forest, savanna and scrub vegetation, from sea-level up to 1700 m altitude; ''A. chinensis'' has been cultivated up to 2400 m. They occur in areas with a seasonal climate, often on sandy soils or otherwise well-drained locations. ''A. dolichadena'' prefers swamp forest. ''A. retusa'' is a littoral species. In the Philippines ''A. acle'' is commonly associated with molave ( ''Vitex parviflora'' A.L. Juss.). In Papua New Guinea ''A. procera'' is commonly found in fire-induced grasslands in association with ''Eucalyptus'' . Several species can be planted in rocky and shallow sites with a pronounced dry season of at least 4 months.

'''== Silviculture''' == ''Albizia'' is easy to propagate from seed. Direct sowing is often applied, as planting out nursery-grown plants disturbs the long taproot which develops rapidly in young seedlings; in the latter case a survival rate of as low as 4% has been recorded. Some 5-10 seeds per planting hole is usually satisfactory for direct sowing. Cuttings can also be used. Seed should be collected from the tree as it is very susceptible to insect attack and rotting. Seed viability is usually high and seed can be stored for up to 5 years without serious decline in viability. Available seed counts per kg are: ''A. acle'' about 240, ''A. chinensis'' 49 500-52 000, ''A. lebbeck'' 7000-10 500, ''A. lebbekoides'' 49 000-59 000 and ''A. procera'' 21 000-41 000. Pretreatment of seed with boiling water, concentrated sulphuric acid or by nicking the seed-coat is usually recommended to overcome dormancy, but untreated seed of various species gave 20-80% germination. To assure optimal germination, seeds should be sown in full light. ''A. lebbeck'' and ''A. procera'' form nitrogen-fixing nodules in the nursery without any inoculation treatment. When sterilized soil was inoculated with ''Rhizobium'' obtained from the nodules of a large ''A. lebbeck'' tree, however, the seedlings from that tree developed optimally. Seedlings are stumped before planting; in ''A. lebbeck'' the stem is cut back to 5 cm, the roots to 15 cm, whereas in ''A. procera'' a shoot length of 10-20 cm and a root length of 20-40 cm with a diameter at the collar of 0.5-1.0 cm are recommended. Seedlings up to 1 m tall have been successfully planted as bare-rooted stock. Root cuttings have been successful when taken at least 15 cm long and 1 cm in diameter. In trials in Java the mean annual clear bole volume increment was 7.7-8.5 m³/ha for 15-year-old trees of ''A. chinensis'' , 2.8 m³/ha for 12-year-old ''A. lebbekoides'' trees and 6.7 m³/ha for 12-year-old ''A. procera'' trees. In these trials ''A. lebbekoides'' developed a poor stem form due to forking and formation of low and heavy branches. In the Philippines ''A. chinensis'' yielded 10-12 m³/ha/year on fertile sites. Lopping the branches for fodder and coppicing are very well tolerated. A rotation of 10-15 years is recommended for ''A. lebbeck'' planted for fuelwood, and of 30 years for timber production. The fungus ''Fusarium oxysporum'' is a serious disease of several ''Albizia'' species, causing gummosis of the vessels and eventually leading to death. In the Philippines the following pests have been observed in ''A. acle'' : ''Lophococcus convexus'' , a scale insect attacking and killing smaller branches, caterpillars of the faggot worm ''Clavia cremeri'' feeding on the leaves, and a flat-headed woodborer, ''Chrysochroa fulminans'' , whose larvae feed on the sapwood, possibly girdling the tree inside and whose adults feed on leaves and green bark.

As the timber of several ''Albizia'' species, especially that of ''A. acle'' and ''A. procera'' , is of good quality and growth is moderately fast their potential deserves further exploration.