Difference between revisions of "Barringtonia (PROSEA Timbers)"

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Plant Resources of South-East Asia Introduction

List of species

Barringtonia J.R. Forster & J.G. Forster

Protologue: Charact. gen. pl.: 38 (1775).

Family: Lecythidaceae

Chromosome number: x= unknown;B. acutangula:n= 13, 2n= 26,B. racemosa: 2n= 52

Vernacular names

• Putat (trade name), vutu (Pacific, trade name). Barringtonia (En). Brunei: angas gimpalang, angas gimplang
• Indonesia: butun (general), keben (Javanese), songgom (Sundanese)
• Malaysia: tampalang (Sabah)
• Philippines: botong, ulam (Tagalog). Burma (Myanmar): kyi-bin, kyi-gyi
• Thailand: chik.

Origin and geographic distribution

Barringtonia comprises about 40 species which occur from tropical and subtropical regions of East Africa (1 species), Madagascar (2 species) to Afghanistan, Pakistan, India, Sri Lanka, Indo-China, southern China, Taiwan, the Ryukyu Islands, Thailand and the whole of the Malesian region towards northern Australia and the Pacific, east to Samoa and the Society Islands (Tahiti). Malesia represents the centre of diversity of Barringtonia with 32 species occurring there. One species ( B. asiatica ) has been introduced into East Africa, Hawaii, the West Indies and St. Helena.

Uses

The wood of Barringtonia is used for temporary construction, local house building (posts, beams), general planking, flooring, boat building, mouldings, interior finish, handles of non-striking tools, household utensils, agricultural implements, boxes and crates and wooden pallets. The wood is suitable for veneer and plywood manufacturing. It has been applied in various kinds of wood-based panels like hardboard, particle board and blockboard, and has been used for the production of pulp. In India the wood is used additionally for carts, rice pounders and cabinet work. In the Philippines it has been reported that when treated with preservatives the timber can be used to make good ties and paving blocks, and that it might serve as an attractive cabinet wood. In the Nicobar Islands, Papua New Guinea and Pacific islands, the bole is used to make canoes. In the Pacific region the wood has additionally been used for carving and turnery. The wood is sometimes used for fuel.

Several species are planted as ornamentals. B. asiatica has also been planted as wind-break and for shade. Seed of most of the species contains saponins which are used as fish poison; the whole fruit, bark, wood or root is sometimes employed for the same purpose. In the Philippines the fruits are used to poison wild pigs and also for fish-net floats. Young leaves and shoots of some species are eaten as a salad. In Peninsular Malaysia the leaves of B. racemosa are used as a traditional vegetable with medicinal properties (against high blood pressure and as a depurative). Pounded leaves are said to cure chicken pox. In India B. acutangula is used for the production of honey. Bark, leaves and fruits of B. asiatica have been used medicinally for treating sores. In the Philippines its leaves have been topically applied against rheumatism and the seed as a vermifuge. A decoction of the leaves of B. macrostachya is said to cure stomach-ache. An infusion of the leaves and bark of B. calyptrata has been used to treat chest pains and fever.

Production and international trade

As the trees are often not large enough to be converted in saw-mills and supplies are small, utilization of the timber of Barringtonia is limited and it is not sold on the international market. In local trade, however, it is sold in mixed consignments of light or medium hardwood. "Putat" is the South-East Asian standard trade name for timber of Barringtonia spp. and Planchonia spp. ( Lecythidaceae ).

Properties

Barringtonia yields a medium-weight hardwood with a density of 480-815 kg/m³at 15% moisture content. Heartwood cream-white, pale yellow-brown, sometimes with reddish tinge, not differentiated from the sapwood; grain straight to interlocked; texture moderately fine and even. Growth rings indistinct, boundaries sometimes indicated by darker zones or by narrow, discontinuous layers of parenchyma; vessels medium-sized to moderately large, solitary and in radial multiples of 2-4, rarely in clusters ( B. calyptrata ), open; parenchyma moderately abundant, paratracheal scanty, vasicentric, aliform or occasionally confluent, and apotracheal diffuse-in-aggregates, visible with a hand lens, in B. asiatica also in regular bands both wider and narrower than the vessels; rays moderately broad or broad, visible to the naked eye; ripple marks absent.

Shrinkage upon air drying is moderate to high and it takes about 2 months and about 5 months, respectively, to air dry 13 mm and 38 mm thick boards of B. pendula , which is fairly slow. There is only a slight risk of insect attack and stain during air drying; severe cupping was observed in samples from Sabah. The wood kiln dries well from the green state, but some surface checking and slight warping occurs in back-sawn material. Boards of 25 mm and 50 mm thick of B. samoensis take 4-5 days and 8-9 days, respectively, to kiln dry. The wood is soft to moderately hard and fairly weak. It is easy to work and plane with hand and machine tools, although sawing has been reported to be difficult for B. asiatica ; the finish may be slightly fibrous, and hence very sharp tools are required. Peeling of B. pendula did not present problems; the veneers dried easily but were liable to develop end splits and waviness. The wood is non-durable; the sapwood is permeable, the heartwood moderately resistant to pressure impregnation. The wood is liable to sap-stain, termite, and marine borer attack. The sapwood is susceptible to Lyctus .

The gross energy value of the wood of B. acutangula is about 20 650 kJ/kg. The seed is especially rich in saponins.

See also the tables on microscopic wood anatomy and wood properties.

Botany

Evergreen shrubs or small to medium-sized or occasionaly large trees up to 30(-47) m tall; bole branchless for up to 18 m, up to 60(-100) cm in diameter, rarely with thick buttresses spreading to 1.2 m, sometimes with steep, thick buttresses or a fluted base ( B. pendula ); bark surface slightly grooved and longitudinally fissured, cracked or scaly, sometimes smooth or dippled with roundish scales ( B. scortechinii ), thick, lenticels often distinctly diamond-shaped, brown, red-brown or grey, sometimes tinged with pink; inner bark finely, firmly fibrous, yellow-brown to pink or white with yellowish streaks ( B. asiatica ), without exudate. Leaves arranged spirally, crowded towards the ends of twigs, simple, obovate or obovate-oblong, dentate (except in B. asiatica ), glabrous, with numerous lateral veins; stipules small, triangular, caducous. Flowers in a many-flowered, terminal or axillary, or sometimes cauliflorous, erect or pendulous raceme or spike, white, pink or red, often very large, very fragrant, fluffy from the numerous stamens; calyx rupturing circumscissile or into 2-4(-5) segments or with 4(-5) free lobes, the tube angular or winged; petals (3-)4(-5), free but connate to the filament tube; disk circular; ovary inferior, 2-4-locular with 2-6 ovules in each cell, with a single style. Fruit a medium to large, 1-seeded berry, ovoid to fusiform, smooth, grooved or angled, crowned by the persistent calyx. Seedling with hypogeal germination; cotyledons absent (seed containing a swollen hypocotyl); shoot with scales at the first few nodes.

Branching is predominantly sympodial. Flowering takes place during the night with the corolla opening early in the evening and falling the next morning. In B. asiatica only 1 flower per inflorescence opens every night whereas in B. racemosa about half of the flowers in a single inflorescence bloom simultaneously. Most species flower throughout the year but full bloom is generally reached in May and August to September. Pollination of the fragrant flowers is generally by bats or insects (mainly moths) which are also attracted by the copious nectar. After shedding of the flowers, the inflorescences are often crowded with ants attracted by the nectar. A comparatively high percentage of the fruits is seedless. In lowland dipterocarp forest in Peninsular Malaysia the flowering-to-fruiting period of B. pendula is 8-18 weeks. Seed dispersal is usually by squirrels and other animals that feed on the fruits. Fruits of B. asiatica and several other species are buoyant thanks to the thick layer of spongy, fibrous pericarp, and are dispersed by sea currents.

The family Lecythidaceae is sometimes split into three separate families, with Barringtonia being a member of the Barringtoniaceae . Species of Barringtonia are extremely variable in e.g. leaf shape, size and margin, position and shape of spikes, and fruit shape and size. Despite this polymorphism the species are generally easy to recognize.

Ecology

Most Barringtonia species are quite common elements of the canopy layer in evergreen, primary or sometimes secondary, lowland rain forest. They often occur on river banks or in estuaries, or in permanently or seasonally swampy locations but some species prefer well-drained habitats. Most species are found below 600 m but a few grow in montane forest up to 1500(-2000) m altitude. Barringtonia species are present in areas subject to perhumid or seasonal conditions. B. asiatica is a very characteristic element of the coastal fringe forest ( Barringtonia formation) and is associated with other trees like Calophyllum inophyllum L., Casuarina equisetifolia L., Hibiscus tiliaceus L. and pandans ( Pandanus spp.). B. racemosa may form almost pure stands along tidal rivers or in upper mangrove swamps.

Silviculture Barringtonia can be propagated by seed or by cuttings. Seeds of B. asiatica have about 70% germination in 36-63 days, compared with about 75% for B. scortechinii in 5-15 months. Sown fruits of B. macrostachya have about 40% germination in 9-22 months. Seeds of B. acutangula should be sown in full light, giving a germination of about 90%. B. asiatica can also be propagated by cuttings. B. asiatica is not resistant to fire.

Genetic resources and breeding

As trees are not often harvested for timber, there is no threat to the genetic diversity of Barringtonia . There are no records of Barringtonia in seed or germplasm banks.

Prospects

In view of the poor wood quality it is unlikely that the importance of Barringtonia for timber, either by exploiting natural forest or by establishing plantations will increase.

Literature

130, 151, 162, 163, 198, 209, 267, 302, 304, 340, 348, 387, 406, 436, 438, 450, 464, 536, 543, 678, 679, 751, 752, 800, 828, 829, 831, 861, 872, 889, 934, 940, 1038, 1053, 1169, 1192, 1221, 1232, 1236, 1239, 1242.