Calamus exilis (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Calamus exilis Griffith

Protologue: Palms of British India: 51 (1850).

Family: Palmae

Chromosome number: 2n= unknown

Synonyms

Calamus ciliaris Blume sensu Ridley (1893), C. curtisii Ridley (1907), C. ciliaris Blume var. peninsularis Furt. (1956).

Vernacular names

• Indonesia: uwi pahe (Palembang), rotan gunung
• Malaysia: rotan paku, rotan lilin.

Origin and geographic distribution

C. exilis is widespread in Peninsular Malaysia and Sumatra.

Uses

Both in Peninsular Malaysia and in Sumatra this rattan is mostly used locally in binding and weaving. The local people of Sungai Tutung, Kerinci, Sumatra have for years produced baskets using the split cane of this rattan. The same material can be used to produce handicrafts such as lamps and vases.

Production and international trade

To date, C. exilis has been collected from the wild mostly for local consumption. Although it is known that this rattan is also sold, the actual amount traded internationally is not known.

Properties

C. exilis produces a good quality slender cane suitable for binding and weaving.

Botany

Slender solitary or clustering rattan. Stem climbing to 10 m or sometimes to 15 m high; stem without leafsheaths 48 mm in diameter, with sheaths 820 mm; internodes 15 cm or more. Leaf 4590 cm long including the petiole; leafsheath dull greybrown, variable in armature, always densely covered by minute scabrid spines, often no other spines present or two or more triangular spines present on one leafsheath, or leafsheath densely armed with flat triangular spines irregularly arranged or arranged in partial whorls; knee and whip (flagellum) present on the sheath; petiole up to 30 cm long, scabrid as the sheath; rachis to 60 cm long, with rusty hairs along the upper surface, armed with scattered spines on the lower surface; leaflets 2240 pairs, very regularly arranged, linear lanceolate, up to 40 cm×2 cm, the upper surface usually densely hairy. Inflorescence to 1.5 m long, with terminal whip, the male and female superficially similar, usually the female more robust, the male branching to 3 orders and the female to 2, the whole inflorescence scabrid as the sheath; bracts tightly tubular; first order branches 27, rather distant; flowerbearing branches slender, to 7 cm long in the female, shorter in the male; male flower greenishyellow, 6 mm×2 mm; female flower on a conspicuously stalked disk, 4 mm×3 mm, each borne in a pair together with a sterile male flower. Mature fruit ovoid to oblong, 22 mm×8 mm, with strawcoloured scales. Seed 12 mm×3 mm, sinuous grooved, brainlike, covered with a thin green intensely bitter and fetid sarcotesta; endosperm homogenous, embryo lateral. Seedlingleaf pinnate, with rusty coloured hairs along rachis and about 10 leaflets on each side of the rachis, the uppermost leaflets much larger and broader than the lowermost.

No information on growth and development is available for this rattan. It is only known that C. exilis is a forest undergrowth species and in one trial at FRIM, Kepong, grew at a rate of 120 cm/year.

Ecology

C. exilis is found in a wide variety of forest types. It has been found in peatswamp forest, but mostly on ridges in hill and lower montane forests.

Agronomy

A plantation trial has been established in Sungai Tutung, Kerinci, Sumatra. Sucker shoots were used as planting material, and transplanted beneath perennial crops. It was reported that after two months survival was high.

Genetic resources and breeding

Besides the plantation trial at Kerinci, Sumatra, a few plants of C. exilis have been cultivated at the arboretum at FRIM, Kepong, Malaysia.

Prospects

This rattan may be cultivated for local use.

Literature

• Dransfield, J., 1979. A manual of the rattans of the Malay Peninsula. Malayan Forest Records No 29. Forest Department, Kuala Lumpur. p. 176.
• Siebert, S.F., 1989. The dilemma of a dwindling resource: Rattan in Kerinci, Sumatra. Principes 33(2): 7987.

Authors

P. Kramadibrata