Colona Cav. (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Colona Cav.

Protologue: Icon. 4(2): 47, t. 370 (1798).

Family: Tiliaceae

Chromosome number: x= unknown;2n= unknown

Major species and synonyms

• Colona javanica (Blume) Burret, Notizbl. Bot. Gart. Berlin 9: 810 (1926), synonyms: Columbia javanica Blume (1825), Grewia involucrata Blume (1825), Colona integrifolia (Ridley) Burret (1926).

• Colona serratifolia Cav., Icon. 4(2): 47 (1798), synonym: Columbia serratifolia (Cav.) A. DC. (1824).

Vernacular names

• C. javanica : Indonesia: sampora, jalupang (Sundanese), kayu ules (Lampung)
• Thailand: po nguang, po (peninsular).

• C. serratifolia : Malaysia: jelunut
• Philippines: anilau (Tagalog, Bikol, Bisaya), mamaued (Tagalog), salag (Bikol).

Origin and geographic distribution

Colona comprises 18-30 species distributed from India and Bangladesh eastward through South-East Asia to the Solomon and Caroline Islands and northward to southern China. C. javanica is found in Thailand, Laos, Peninsular Malaysia, the Nicobar Islands (Camorta), Indonesia and the Philippines. C. serratifolia is distributed from Peninsular Malaysia (eastern coast) through Borneo and throughout the Philippines.

Uses

In Java the bast of C. javanica is made into fishing nets and rope used for all domestic purposes requiring strong rope, for instance in the tethering of buffaloes. In South Sumatra, strips from the inner bast of stems or branches up to 15 cm wide are woven into mats on which rice is dried, whereas bast from older trees is used to make walls for houses and barns. C. serratifolia bast strips have been made into cords in the Philippines, where, despite the weakness of its fibre, it has been popular in Los Baños and surrounding towns.

Timber from C. javanica sometimes serves for house construction in Indonesia, but it is not valued very highly. In Thailand it is used for cabinet work.

Production and international trade

No production statistics are available for C. javanica or C. serratifolia . Their products do not enter international trade.

Properties

Coarse but very strong ropes are made by simply twisting the bark of C. javanica . With better processing finer, rather strong ropes can be made. The fibre obtained from the bark of C. serratifolia , however, is weak, especially when dry. The fibres of C. serratifolia are arranged in pyramidal to narrow-rectangular groups, each subdivided into 1-10 strips, which can be separated easily. The ultimate fibre cells are (3-)5(-7)-sided (polygonal), (1.0-)1.6(-2.5) mm long and (5-)14(-27) μm wide, with a lumen width of (1-)4(-8) μm. Freshly isolated fibre strips are yellowish, but upon drying they turn pale brown.

A red dye is obtained from the bark of C. serratifolia . Hydrocyanic acid is present in the leaves, roots and stems (traces). The wood density of C. serratifolia is 0.33 kg/dm³.

Adulterations and substitutes

Many natural and artificial substitutes are available for Colona as a source of cordage, natural ones including other Tiliaceae , such as Grewia and Triumfetta spp.

Description

Usually small trees. Leaves alternate-distichous, simple, base often unequal-sided, palmately 3-7-veined, margin finely dentate to serrate. Inflorescence a lax terminal or axillary panicle of small, 3-flowered cymes; flowers bisexual; sepals 5, free, hairy outside, glabrous inside; petals 5, free, glabrous, glandular at base; receptacle raised, slightly lobed; stamens numerous, borne on apex of receptacle, filaments free and filiform, anthers dorsifixed; ovary 3(-5)-locular, each locule with 2-4 ovules; style narrow, tapering to the pointed stigma. Fruit subglobose schizocarp with 3(-5) longitudinal wings, breaking up into 3(-5), persistently connate, 2-alate, 1-4-seeded, indehiscent mericarps.

• C. javanica . A tree, up to 15(-25) m tall, stem diameter up to 45 cm. Leaves with petiole 0.2-5 cm long; blade ovate to oblong, 5-30 cm × 2-18 cm, base oblique-cordate and 4-6-veined, margin serrate to serrulate, apex acutely acuminate to caudate, secondary veins 3-5 pairs, scalariform and reticulate veins distinct and always depressed on upper surface, petiole and lower blade surface densely brown stellately tomentose; leaves along the inflorescence stipule-like, those of suckers large with petiole 10-13 cm long, blade subcircular, 25-35 cm in diameter. Inflorescence 10-20 cm long, most parts densely brown stellately tomentose; pedicel articulate, 5-7 mm long; flowers odourless, brownish, diameter about 1 cm; sepals oblong, 5-7 mm long, inside yellow, red-dotted, appressed hairy; petals oblong-spatulate, 4.5-6 mm × 1.5-2 mm, inside yellow, red-dotted, glabrous; stamens glabrous; ovary subglobose, diameter 1-2 mm, hairy; style 3-4 mm long. Fruit ovoid or obovoid, 3-winged, 7.5-10 mm × 20-30 mm (wings included). Seed embedded in mucus.

• C. serratifolia . A tree up to 15 m tall, with densely hairy twigs. Leaves with petiole 6 mm long; blade lanceolate, 9.5-24 cm × 3.5-7.5 cm, base oblique, margins with widely spaced, prominent teeth, apex with a long tip, upper surface glabrous, lower surface velvety white-hairy, secondary veins 5-7 pairs and prominently raised below. Flowers 6-7 mm long, petals pink and yellowish or reddish. Fruit about 1 cm long, 3-4 winged.

Growth and development

In West Java C. javanica is evergreen and flowers from March to December. In Thailand flowering is from June to August and fruiting from December to February. C. javanica produces suckers.

Other botanical information

Several other Colona species are known to yield fibre (see Minor fibre plants). The Philippine vernacular name "anilau" for C. serratifolia has also been recorded for C. lanceolata (Warb.) Burret and C. blancoi (Rolfe) Merrill, the name "mamaued" for C. blancoi, and the Malaysian vernacular name "jelunut" for Commersonia bartramia (L.) Merrill.

Ecology

Colona is confined to open habitats, particularly secondary forest, rocky seashores and limestone hills. In West Java C. javanica grows up to 300 m altitude, in not very dense, evergreen, heterogenous forest, especially on rather rocky, unfertile soils. It usually occurs scattered and is seldom found in groups. In Thailand it is found up to 800 m altitude in evergreen forest. C. serratifolia needs sun and grows in secondary forest.

Husbandry

Colona is collected from the wild and is not cultivated.

Handling after harvest

In Java coarse, strong ropes are made from C. javanica by removing the green peel from the bast, which is subsequently twisted manually several times. The division of C. serratifolia strips into narrower strips, for the production of finer cords, must be done when they are still fresh, because they become stiff and brittle upon drying. To preserve freshness cord-making is better done in the morning or in cool weather. Wetting of dried fibres can restore them to the fresh condition.

Genetic resources and breeding

In the Nicobar Islands C. javanica is considered a rare and endangered species. No germplasm collections or breeding programmes of Colona are known to exist.

Prospects

C. javanica will at most remain a local source of cordage, as many natural and artificial substitutes are available. The prospects for C. serratifolia are even bleaker, in view of its lower fibre quality.

Literature

• Backer, C.A. & Bakhuizen Van den Brink Jr, R.C., 1963. Flora of Java. Vol. 1. P. Noordhoff, Groningen, the Netherlands. p. 394.
• Brown, W.H., 1954. Useful plants of the Philippines. Vol. 2. Reprint. Technical Bulletin 10. Department of Agriculture and Natural Resources. Bureau of Printing, Manila, the Philippines. pp. 380-381.
• Heyne, K., 1927. De nuttige planten van Nederlandsch-Indië [The useful plants of the Dutch East Indies]. 2nd Edition. Departement van Landbouw, Nijverheid en Handel in Nederlandsch Indië. (3rd Edition, 1950. W. van Hoeve, 's-Gravenhage, the Netherlands / Bandung, Indonesia). pp. 1023-1024.
• Kochummen, K.M., 1972. Tiliaceae. In: Whitmore & Ng (Editors): Tree flora of Malaya. Vol. 2. Malaysian Forest Records No 26. Longman Malaysia Sdn. Berhad, Kuala Lumpur, Malaysia. pp. 349-412. 5 Mendiola, N.B., 1917. A study of Philippine bast fibers. The Philippine Agriculturist and Forester 6: 6-39.
• Phengklai, C., 1993. Tiliaceae. In: Smitinand, T. & Larsen, K. (Editors): Flora of Thailand. Vol. 6. Part 1. The Forest Herbarium, Royal Forest Department, Bangkok, Thailand. pp. 10-80.

Authors

A.T. Karyawati & D. Darmakusuma