Calamus tumidus (PROSEA)
 |
Introduction |
Calamus tumidus Furtado
- Protologue: Gardens' Bull. Singapore 15: 105 (1956).
- Family: Palmae
- Chromosome number: 2n= unknown
Vernacular names
- Rotan manau tikus (general throughout Peninsular Malaysia and Sumatra)
- Malaysia: rotan manau buku hitam (northern Peninsular).
Origin and geographic distribution
C. tumidus is a common and distinctive rattan in the lowlands of the eastern part of Peninsular Malaysia and in Sumatra.
Uses
The canes of larger diameter are sold as rotan manau in the trade, and used in furniture making while smallerdiameter canes are sold with other smallerdiameter canes for various uses including parts of furniture.
Production and international trade
The amount of cane produced and entering international trade is not known.
Properties
An excellent cane whose quality is affected by poor processing and depends on factors such as age, moisture content and light conditions during growth. The diameter of the cane is not as regular as that of C. manan Miq. and it also has shorter internodes.
Description
Solitary, high climbing, dioecious rattan with stems eventually reaching over 60 m. Stem without leafsheaths about 12 mm in diameter near base, and about 25 mm in upper part of the mature plant, with sheaths to about 45 mm in diameter; upper internodes about 12 cm long, lower internodes to 30 cm. Leaf robust, cirrate, to about 4 m long including the cirrus 1.5 m in length; leafsheath with large spines and indumentum; knee greatly swollen; ocrea short, rather inconspicuous; petiole about 30 cm in length, newly emerged petiole reddishbrown to crimson in colour, quickly turning dull yellowishgreen, lower and upper petiole surfaces unarmed and without indumentum; leaflets about 25 on each side of the rachis grouped in pairs, about 40 cm×6 cm, pale yellowishgreen to glaucous, conspicuously white waxy on the lower surface when young, black bristly along margins. Inflorescences, male and female superficially similar, to about 1 m long with spiny bracts and up to 8 partial inflorescences on each side of the rachis; rachillae about 15 cm long. Mature fruit ellipsoid, about 22 mm×18 mm, shortly beaked, covered with 15 vertical rows of convex yellowishbrown scales. Seed 1.6 cm×1.2 cm×1 cm, flattened, covered in yellowishgreen sarcotesta, irregularly pitted and deeply ruminate. Seedlingleaf bifid.
Growth and development
Seeds germinate between 6 to 31 weeks. After about 24 months from field planting, cirri develop after which the aerial stems may grow (at rates still unknown). No phenological work has been documented. Plantationgrown C. tumidus is estimated to be harvestable at year 15.
Other botanical information
C. tumidus differs from the closely related C. manan in that the former is smaller, has different leafsheath armature and a very large bulbous swollen knee.
Ecology
C. tumidus is very common in the lowlands of the eastern part of Peninsular Malaysia and in Jambi Province of Sumatra. It is most commonly found in freshwater swamp forest; it has also been found in peatswamp forest and on alluvial flats. It is apparently absent from hillslopes where C. manan replaces it.
Propagation and planting
Propagation is best effected from seeds. The fruit wall and the fleshy seedcoat must be removed before sowing and the clean seeds kept moist, as any drying out will cause the embryo to die. Seeds are usually sown in seedbeds in the shade and potted in polybags when the first leaf has emerged. Once potted, seedlings should be kept in the shade and provided with plenty of moisture without waterlogging. Seedlings are usually ready for planting 912 months after transplanting into bags and require tree support. Seedlings require about 50% relative light intensity for establishment and growth. The planting distance should be 6 m×3 m or variations of this.
Husbandry
Once the seedlings are planted in the field, thinning of tree canopy along planting lines in the establishment phase may be necessary to allow light to reach the seedlings. During the first three years, about 50 g of compound fertilizer per seedling is added per year.
Diseases and pests
Few diseases and pests have been recorded on Calamus species generally. In the field, collar rot disease of plant seedlings is so far the only serious fungal disease. In the nursery, leaf diseases (shot holes, brown rings and brown spots) are evident on the leaves of young growing stock of C. tumidus . The severity varies from mild to severe and control is by spraying fungicide at 10day intervals.
Calamus leaves are reported to be attacked by Artona catoxanta (moth), Botryonopa sanguinea , Protocerius colossus and Rhabdonemis leprosa (all beetles). The fruits have been observed to be attacked by beetles before they are ripe. Stunted growth may result from beetle larvae damaging the swollen basal part of the stem.
Harvesting
Harvesting of the stems varies slightly from place to place. Essentially, it involves dragging the rattan from the canopy, removing dead leafsheaths and debris and discarding the uppermost 23 m, which are immature and too soft for use. The leafsheaths and debris are usually removed by coiling and pulling the rattan stem around a conveniently placed small tree trunk, resulting in a clean stem. The cane is then cut into 3 m lengths suitable for bundling and transport out of the forest to the processor.
Handling after harvest
C. tumidus is treated for protection against attack by staining fungi and powderpost beetle. The canes are boiled in a mixture of diesel and coconut oil, or of diesel and kerosene, or of diesel and palm oil, for varying lengths of time. After boiling, the canes are rubbed with sawdust, ragwaste or gunny sacking and then made into a bundle tied loosely at one end and stood upright with the untied end on the ground in wigwamlike fashion for drying in the sun for a period of 12 (rarely three) weeks. They may also be fumigated over burning sulphur, which not only prevents attack by diseases and pests but also improves the colour of the rattan skin.
Genetic resources
No attempt has been made to establish a collection to represent the considerable variation found in this species in the wild. However, C. tumidus is represented in silvicultural plots.
Breeding
No breeding has been carried out. Early selection and provenance trials are needed since C. tumidus is sold as rotan manau (cane with larger diameter) in the market.
Prospects
The future of this and other commercial rattan species in the wild is uncertain, owing to severe overexploitation. As both C. manan and C. tumidus are solitary species, and as C. tumidus is usually of smaller diameter, C. manan is preferred for cultivation.
Literature
- Aminuddin Mohamad, 1990. Ecology and silviculture of Calamus manan in Peninsular Malaysia. Ph.D. Thesis. University of Wales. 245 pp. [mimeographed]
- Dransfield, J., 1979. A manual of the rattans of the Malay Peninsula. Malayan Forest Records No 29. Forest Department, Kuala Lumpur. pp. 145147.
- Manokaran, N., 1978. Germination of fresh seeds of Malaysian rattans. Malaysian Forester 41: 319324.
- Manokaran, N., 1985. Some information of rattan species undergoing silviculture trials. Rattan Information Centre Bulletin 4(4): 14.
- Norani, A., Tho, Y.P. & Hong, L.T., 1985. Pests and diseases of rattans and rattan products in Peninsular Malaysia. In: Wong, K.M. & Manokaran, N. (Editors): Proceedings of the rattan seminar, Kuala Lumpur, 24 October 1984. Rattan Information Centre, Forest Research Institute of Malaysia, Kepong. pp. 131135.
Authors
Aminuddin bin Mohamad
