3032

11: Auxiliary plants

Paraserianthes falcataria (L.) Nielsen

Bull. Mus. Natn. Hist. Nat., 4e sér., sect. B, Adansonia 5: 327 (1983).

LEGUMINOSAE - MIMOSOIDEAE

2n = 26

Albizia moluccana Miquel (1855), Albizia falcata sensu Backer (1908), Albizia falcataria (L.) Fosberg (1965).

Paraserianthes (general), batai (timber trade name) (En). Peacock's plume (Am). Brunei: puah. Indonesia: jeungjing (Sundanese), sengon laut (Javanese), sikat (Banda). Malaysia: batai (Peninsular, Sabah), kayu machis (Sarawak). Papua New Guinea: white albizia. Philippines: Moluccan sau, falcata.

Paraserianthes falcataria is native to the Moluccas, New Guinea, the Bismarck Archipelago including the Admirality Islands and the Solomon Islands. It is widely planted throughout the humid tropics.

Paraserianthes falcataria is planted extensively for reforestation and afforestation of denuded and eroding land. Because it is very fast- growing, the wood is widely used for fuelwood and charcoal production in spite of its low density and energy value. It is an important shade tree for tea and other crops, its fast growth and good shading properties outweighing its sensitivity to strong winds and its relatively short life. It is being tested in alley-cropping systems, although its tolerance of coppicing is limited.
Paraserianthes falcataria is a major source of paper pulp and has been used for the manufacture of viscose rayon. The comparatively soft timber, called batai in trade, is suitable for general utility purposes such as light construction, furniture and cabinet work, lightweight packing materials and pallets. It is a well-known source for match wood. Because the wood is fairly easy to cut, batai is also suitable for wooden shoes, musical instruments, toys and novelties, forms and general turnery. Batai is an important source of lightweight veneer and plywood and is very suitable for the manufacture of particle board, wood-wool board and hardboard, and has recently also been used for blockboard.
The bark yields a gum, has tanning properties, and it is also used for packing. The leaves are fed to poultry, goats and sheep. Paraserianthes falcataria is also planted as an ornamental.

In Japan there is a great demand for batai wood for manufacturing lightweight furniture and furniture components (e.g. drawer sides); particularly the butt log portion is used for these purposes. Timber from natural and plantation-grown trees is imported in Japan, but no statistics are available.

In Cameroon, the mineral composition of the leaves of 1-year-old trees per 100 g was approximately: N 2.5 g, P 0.15 g, K 0.7 g, and Ca 1.17 g; the composition of the wood: N 0.9 g, P 0.1 g, K 0.4 g, and Ca 0.3 g. In an alley cropping experiment in Western Samoa, Paraserianthes falcataria was pruned 4 times per year, each pruning producing about 1 t/ha total dry matter. The mineral composition of the prunings was: N 5.3 g, P 0.6 g, K 0.8 g, Ca 0.6 g, and Mg 0.3 g.
The density of the wood of Paraserianthes falcataria is (230—)300—500 kg/m³ at 12% moisture content. The energy value of the wood is 19 500—20 600 kJ/kg. Batai is a lightweight, soft to moderately soft wood. The colour of the heartwood ranges from whitish to pale pinkish-brown or light yellowish- to reddish-brown (in older trees); the heartwood of younger trees is not clearly demarcated from the pale coloured sapwood, but it is more distinct in older trees. The grain of the wood is straight or interlocked, texture moderately coarse but even. Batai wood usually air-dries fairly rapidly without serious degrade, and the kiln-drying properties are satisfactory. It is easy to work with machines and hand tools, but is reported to be abrasive to saws. Sharp knives are needed to produce smooth surfaces in planing, otherwise grain may pick up badly. The wood moulds and mortises well but tension wood, if present, will give a woolly surface. Boring is usually easy, but the nailing properties are rated as poor. Glueing is no problem. Batai can be peeled and sliced easily into veneer of good quality. It is very suitable for particle boards, while its pulp is rated among the best of tropical woods, comparable to good-quality eucalypt pulp, and requiring only minimal bleaching.
The wood is not durable when used outdoors, with an average service life in contact with the ground of 0.5—2 years in graveyard tests. It is very vulnerable to termites, powder-post beetles and fungi. The wood can be treated easily with preservatives, e.g. a mixture of creosote and diesel fuel. Stake tests showed an average life of treated wood in contact with the ground of 15 years under tropical conditions.
Sawdust from dry wood may cause allergic reactions and may irritate nose and throat. Batai wood contains 49% cellulose, 27% lignin, 15.5% pentosan, 0.6% ash and 0.2% silica.
Preliminary test results indicate that the leaves of Paraserianthes falcataria are a good fodder: daily liveweight gains of 57 g were found in sheep, about 50% higher than from leaves of Calliandra calothyrsus Meisn. and Gliricidia sepium (Jacq.) Kunth ex Walp.
The weight of 1000 seeds is 16—26 g.

A medium-sized to fairly large, unarmed tree up to 40 m tall, bole straight and cylindrical in dense stands, branchless for up to 20 m and up to 100 cm or sometimes more in diameter; bark surface white, grey or greenish, smooth or slightly warty, sometimes shallowly fissured and with longitudinal rows of lenticels, inner bark white, yellowish, pink or pale red-brown, fibrous; young parts often densely tomentose. Leaves alternate, bipinnate, up to 40 cm long, with (4—)8—15 pairs of pinnae, each pinna with (8—)15—25 leaflets, rachis and pinnae with extrafloral nectaries; stipules linear or filiform, caducous, 3—5 mm x 0.5—1 mm; petiole 2—8 cm long, with a raised gland in the distal half; leaflets oblong-falcate, 6—15 mm x (2—)3—6 mm, sessile, densely appressed puberulous. Inflorescence a paniculate raceme, up to 30 cm long; flowers bisexual, 5-merous, subtended by bracts; calyx valvate, tubular to cup- or bell-shaped, 1.5—3 mm long; corolla valvate, funnel- or bell-shaped, 4—6.5 mm long, creamy to yellowish, sericeous all over; stamens numerous, 10—15 mm long, white, filaments fused into a 3.5 mm long tube at base, anthers quadrangular, minute; ovary solitary, glabrous. Fruit a chartaceous, flat, straight pod, 7.5—10.5 cm x 1.3—1.7 cm, narrowly winged along the ventral suture, dehiscent along both sutures, puberulous, usually glabrescent, many-seeded. Seed oblongoid, flat, 6—7.5 mm x 3—4 mm, olive-green, with oblong areole about 5 mm long.

Paraserianthes falcataria grows so fast that it is sometimes called the 'miracle tree'. It is even mentioned in the Guinness Book of Records as the world's fastest growing tree. On good sites, trees may attain a height of 7 m in a little more than one year. Trees reach a mean height of 25.5 m and a bole diameter of 17 cm after 6 years, 32.5 m and 40.5 cm after 9 years, 38 m and 54 cm after 12 years, and 39 m and 63.5 cm after 15 years, respectively. Growth of young trees in a P-deficient soil is promoted by inoculation with the mycorrhizal fungi Gigaspora margarita and Glomus fasciculatum. Inoculation with Bradyrhizobium has proved to be effective, and especially beneficial in combination with mycorrhizal infection.
Trees may already flower at the age of 3 years. Two flowering periods per year have been observed in Peninsular Malaysia and Sabah. Ripe pods appear approximately 2 months after flowering. The pods dehisce when ripe, often still attached to the tree, scattering the seeds on the ground.

Three subspecies are recognized in Paraserianthes falcataria. Subsp. falcataria occurs in the Moluccas and New Guinea, subsp. solomonensis Nielsen in the Solomon Islands, and subsp. fulva (Lane-Poole) Nielsen (synonyms: Albizia fulva Lane-Poole and Albizia eymae Fosberg) in the central mountains of New Guinea; the latter subspecies has densely puberulous to tomentose pods and a woolly leaf rachis.

As a pioneer species, Paraserianthes falcataria occurs in primary but more characteristically in secondary lowland rain forest, and also in light montane forest, grassy plains and along roadsides near the sea. It is adapted to per-humid and monsoonal climates with a dry season of up to 2(—4) months and an annual rainfall ranging from 2000—4000 mm, averaging 2800 mm. In its natural habitat it occurs from 0—2300 m altitude. The optimum temperature range is 22—29°C, with mean minimum temperatures of the coldest month of 22—24°C and mean maximum temperatures of the hottest month of 30—34°C. It is found on well-drained sandy and lateritic soils. In natural stands in Irian Jaya Paraserianthes falcataria is associated with e.g. Agathis labillardieri Warb., Celtis spp., Diospyros spp., Pterocarpus indicus Willd., Terminalia spp., and Toona sureni (Blume) Merrill.
When planted, Paraserianthes falcataria can grow on comparatively poor sites and survive without application of fertilizers. However, it does not thrive in poorly drained, flooded or waterlogged soils. It is sensitive to fire and easily damaged by strong wind.

Paraserianthes falcataria is strongly light-demanding and regenerates naturally only when the soil is exposed to sunlight. In the forest, wildlings sprout in abundance when the canopy is open and when the soil is cleared from undergrowth. Wildlings can be successfully collected and potted for planting, but they are delicate and have to be handled carefully.
Seeds are difficult to collect from the ground since they are small. They are usually collected by cutting down branches bearing ripe brown pods. The seeds can be easily collected from felled trees if the fruits happen to be in the right condition. Untreated seeds germinate irregularly; germination may start after 5—10 days but sometimes it is delayed for up to 4 weeks from sowing. To hasten germination and to make it more simultaneous, seed can be soaked in boiling water for 1—3 minutes, or by immersion in concentrated sulphuric acid for 10 minutes and then washing and soaking in water for 18 hours. The germination rate can be as high as 80% to almost 100%.
For storage, seeds are air dried for 24 hours and then packed in polythene bags. Stored at 4—8°C, the germination rate after 18 months may still be 70—90%.
Seed is usually sown by broadcasting, pressed gently into the soil, and then covered with a layer of fine sand up to 1.5 cm thick. The soil in the seed-bed must be loose and well-drained; application of a surface layer of mulch is advisable and excessive shading should be avoided. The seedlings can be transplanted when they have reached a height of 20—25 cm with a woody stem and a good fibrous root system; this stage can be reached in 2—2.5 months. Container plants are often transplanted into the field when 4—5 months old. The stem is cut back to about 10 cm above the root collar, and the taproot to a length of 20—25 cm. The seedlings are usually planted into the field at a spacing of 2—4 m x 2—4 m. The average annual production of seedlings in the Philippines was 2.1 million in the period 1979—1982. Seed tissue has been successfully used for propagation by tissue culture in the Philippines.

As initial growth of Paraserianthes falcataria in plantations is remarkably fast, weeding generally can be limited to 1 complete weeding and 3 spot weedings during the first year. The application of fertilizers may improve the yield; application of 12.5 kg/ha of P has been found satisfactory.
In agroforestry systems a cutting cycle of 10—15 years is normally used, in combination with annual crops in the first year and grazing by livestock in subsequent years. Pure stands give a good protective cover to prevent erosion on slopes, and they are recommended for this purpose in Indonesia and the Philippines in catchment areas sheltered from typhoons. Paraserianthes falcataria coppices fairly well, which is advantageous for pulpwood production, but frequent coppicing as in alley-cropping systems quickly exhausts the trees and results in a high mortality rate and poor regrowth. For timber production, the original stand can be thinned to a density of 250 trees/ha when 4—5 years old, and to 150 trees/ha after 10 years. Trees grown for timber must be pruned, as they have a tendency to fork. The cutting cycle is usually 12—15 years. Trees grown for pulp production have a cutting cycle of about 8 years.

Nursery seedlings are susceptible to damping-off caused by fungi of the genera Fusarium, Phytophthora, Pythium, Rhizoctonia and Sclerotium. Sterilizing the soil before sowing and applying fungicides to soil and seeds may control the disease. The fungus Corticium salmonicolor causes pink canker or salmon canker. At first, light brown lesions appear on the bark of young trees; they gradually enlarge and develop cracks, the colour turns to pale salmon or pinkish and then mycelium mats appear around the lesions. The disease may seriously damage plantations. Plantations can also suffer from other fungal diseases like red root caused by Ganoderma pseudoferrum. An anthracnose seedling disease caused by a Colletotrichum species has been observed in Sumatra. In 1988 and 1989 gall rust disease caused by Uromycladium tepperianum provoked severe damage in Bukidnon Province (Mindanao, the Philippines). The government banned the transport of logs in and out of Bukidnon Province, and planting was suspended.
Plantation pests in Indonesia, Malaysia and the Philippines include stem-borers such as the longicorn beetle Xystrocera festiva and the red borer Zeuzera coffeae (a cossid moth). Leaf-eating caterpillars (e.g. Eurema blanda, Eurema hecabe and Semiothesa emersaria) may attack seedlings and trees. Aphids have occasionally been a problem on seedlings. Insecticides are commonly used to control these pests.

Plantations are clear-cut when the cutting age is reached. Usually harvesting is problem-free as the trees are harvested when still comparatively young and consequently have small and lightweight logs which can be yarded and loaded easily. Rapid extraction, conversion and seasoning of batai wood is necessary to prevent insect attack and infestation by fungi. The wood is particularly prone to sap-staining attack.

Paraserianthes falcataria is a fast grower and the yield is often high. In 8—12-year rotations, mean annual volume increments of (10—)25—30(—40) m³/ha are attained. On fertile soils in Indonesia, mean annual increments of 50—55 m³/ha have even been reached in plantations of 9—12 years old (120 trees/ha when 9 years old and 76 trees/ha when 12 years old).

Paraserianthes falcataria is planted on a large scale throughout the tropics and the genetic resources are quite comprehensive.

Breeding programmes should be conducted to obtain superior trees in respect to bole shape (preferably long and straight without a tendency to fork) and resistance to diseases and pests. Superior trees can be mass-produced by tissue culture.

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Dayan, M.P., 1989. Moluccan sau - Albizia falcataria (L.) Back. RISE (Research Information Series on Ecosystems) Vol. 1(10): 84-97.
Eusebio, M.A., Sinohin, V.O. & Dayan, M.P., 1990. Gall rust disease of Albizia falcataria (L.) Back. RISE (Research Information Series on Ecosystems) Special Issue. 14 pp.
Griffioen, K., 1954. Albizzia falcata, een goede industrie-houtsoort [Albizzia falcata, a good industrial timber]. Tectona 43: 97-110.
Martawijaya, A., Kartasujana, I., Mandang, Y.I., Prawira, S.A. & Kadir, K., 1989. Atlas kayu Indonesia [Indonesian wood atlas]. Vol. 2. Forest Products Research and Development Centre, Bogor, Indonesia. pp. 59-64.
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Nielsen, I., Guinet, P. & Baretta-Kuipers, T., 1983. Studies in Malesian, Australian and Pacific Ingeae (Leguminosae-Mimosoideae): the genera Archidendropsis, Wallaceodendron, Paraserianthes, Pararchidendron and Serianthes, part 2. Bulletin du Muséum National d'Histoire Naturelle, 4e sér., sect. B, Adansonia 5: 335-360.
Peh, T.B. & Khoo, K.C., 1984. Timber properties of Acacia mangium, Gmelina arborea, Paraserianthes falcataria and their utilization aspects. Malaysian Forester 47: 285-303.
Rojo, J.P., Alonzo, D.S. & Ilic, J., 1993. Paraserianthes Nielsen. In: Soerianegara, I. & Lemmens, R.H.M.J. (Editors): Plant Resources of South-East Asia No 5(1): Timber trees: major commercial timbers. Pudoc Scientific Publishers, Wageningen, the Netherlands. pp. 319-325.

J.P. Rojo

Rojo, J.P., 1997. Paraserianthes falcataria (L.) Nielsen. In: Faridah Hanum, I & van der Maesen, L.J.G. (Editors): Plant Resources of South-East Asia No 11: Auxiliary plants. PROSEA Foundation, Bogor, Indonesia. Database record: prota4u.org/prosea