Regarded first as a rather productive timber tree, secondly for firewood (specific gravity = 0.65). The hard, light-brown wood is dense, with narrow sapwood and a straight, close grain. It makes excellent particle board and could possibly be useful for furniture, cabinetmaking, and perhaps even pulp and paper. Capable of being directly sown, the tree appears quite promising for erosion control where adapted (NAS, 1979). Some success is indicated in the use of the species to correct the problem of the Imperata grasslands (Tham, 1979). Sabah foresters have converted 1,200 ha of degraded Imperata grassland into productive forest lands.
No data available.
According to Anderson (1978) the gum contains 5.4% ash, 0.98% N, 1.49% methoxyl, and by calculation, 32.2% uronic acid. The sugar composition after hydrolysis: 9.0% 4-0-methylglucuronic acid, 23.2% glucuronic acid, 56% galactose, 10% arabinose, and 2% rhamnose.
Dust from pods pounded during seed extraction causes a respiratory reaction in some people. No hint of pollen allergies has been reported (NAS, 1983d).
Tree to 30 m tall, bole often straight, to over half the total tree height. Branchlets, phyllodes and petioles glabrous or slightly scurfy. Phyllodes 5–10 cm broad, 2–4 times as long as broad, dark green, chartaceous when dry. The phyllodes have (3–)4 longitudinal main nerves which join on the dorsal margin at the base of the phyllode, secondary nerves fine and inconspicuous. Flowers in loose spikes to 10 cm long, solitary or paired in the upper axils. Flowers pentamerous, the calyx 0.6–0.8 mm long, with short obtuse lobes, the corolla twice as long as the calyx. Pods linear, glabrous, 3–5 mm broad, ca 7.5 cm long when green, woody, coiled and brackish-brown when mature, depressed between the seeds. Seeds lustrous, black, ellipsoid, ovate or oblong, 3.5 x 2.5 mm, the orangish funicle forming a fleshy aril beneath the seed.
Native to the Australian Center of Diversity, the mange tree has been reported to tolerate heavy soil, laterites, low pH, poor soil, slopes, and weeds (NAS, 1979, 1983d). Hybridizes naturally with
Acacia auriculiformis, producing hybrids which grow faster than either parent, but tending to retain the poor form of
A. auriculiformis.
Largely Australian with disjunct distribution of small stands in New Guinea and the Moluccas, as well as in Cape York Peninsula. In Indonesia
A. mangium occurs on Taliabu, the most western island, and Sanana, a southern island of the Sula Island Group and near Waesalan in the southwest of the main Ceran group. Introduced to Banglasesh, Cameroon, Costa Rica, Hawaii, Indonesia, Malaysia, Nepal, Papua, and the Philippines (NAS, 1983d).
Often in grasslands and on margins of lowland primary forests at altitudes of 10–50 m. Probably capable of ranging from Tropical Very Dry to Moist through Subtropical Dry to Wet Forest Life Zones, this species has outperformed
Albizia falcataria, Gmelina arborea (considered among the fastest-growing useful trees on earth, NAS, 1979), and
Pinus caribaea on poor sites such as disturbed or burned sites, on degraded lateritic clay underlain with volcanic rock, on soils so worn out that even shifting cultivation had been abandoned, and on slopes infested with
Eupatorium and/or
Imperata species. Mangium apparently tolerates annual precipitation of 10 to 45 dm or more, mean maximum temperature of 31–34°C in summer, mean minimum temperature of 12–25°C in winter, and pH of 4.2–7.5 (NAS, 1983d). It is reported on entisols and ultisols.
Sometimes sown direstly. During the first two years growth in Sabah Imperata wastelands, trees required some weeding and occasionally insecticidal treatment. Beyond that, little tending is required. Trees coppice readily and flower and fruit profusely and "continuously" (NAS, 1979). Many more details are reported by NAS (1983d).
Large-diameter logs can be sawn or peeled. Viable seed can be harvested only 24 hours after planting (NAS, 1983d). Fourteen-year old trees yield a kilogram of seed.
Said to be a very fast growing species attaining 15 m height and 40 cm DBH in 3 years. They have attained 23 m tall in 9 years.
Yields as high as 30 m
3/ha/yr have been reported, but 20 m
3 has been reported on poor sites. The timber, recommended for testing as firewood, has potential for firewood and charcoal (NAS, 1983d). The wood has 4,800–4,900 kcal/kg. Untended 9-year old stands have yielded 415 m
3 timber per ha, representing annual productivity of 46 m
3 (NAS, 1979). The MAI in Sabah varies from 13.8–44.5 m
3/ha.
There are problems with leaf insects. Mangium has symbioses with the bacterium
Rhizobium and the fungus
Thelephora. Specimens (ca 12%) in Sabah suffer from a heart rot and a "pink disease" (
Corticium salmonicolor). Seedlings in Hawaiian nurseries are attacked by a powdery mildew (
Oidium sp.). Three pinhole borers attack the tree in Sabah, especially on poorer sites. Carpenter ants (
Camponotus sp.) form galleries in the heartwood of young trees. Wood borers of the genus
Xystrocera may be a problem. Seedlings may be defoliated by
Hypomeces squamosus. Scale insects and mealy bugs may also be problematic with young plants (NAS, 1983d).
- Anderson, D.M.W. 1978. Chemotaxonomic aspects of the chemistry of acacia gum exudates. Kew Bull. 32(3):529–536.
- N.A.S. 1979. Tropical legumes: resources for the future. National Academy of Sciences, Washington, DC.
- N.A.S. 1983d. Mangium and other acacias of the humid tropics. National Academy Press, Washington, DC.
- Tham, C.K. 1979. Trials of Acacia mangium Willd. as a plantation species in Sabah. Forest Genetic Resources Information 9. FAO Forestry Occasional Paper 1979 (No. 1).
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