Laccosperma secundiflorum (PROTA)

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Plant Resources of Tropical Africa
Introduction
List of species


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Laccosperma secundiflorum (P.Beauv.) Küntze


Protologue: Rev. Gen. Pl. 2: 729 (1891).
Family: Arecaceae (Palmae)

Synonyms

  • Calamus secundiflorus P.Beauv. (1805),
  • Ancistrophyllum secundiflorum (P.Beauv.) H.Wendl. (1878).

Vernacular names

  • Large rattan, African climbing palm, African rattan palm (En).
  • Palmier-asperge (Fr).
  • Likaw (Sw).

Origin and geographic distribution

Laccosperma secundiflorum is widely distributed in tropical Africa, from Senegal to DR Congo.

Uses

The whole stems are mainly used for furniture framework, but also for binding and for walking sticks, baskets, fish-traps, suspension bridges and drumsticks. Thinner stems are used as rope. Split stems with the pith scraped out are used for basketry, fish-traps and as tying material. In Cote d’Ivoire the split stems are used in the fabrication of traditional drums by securing the goat-skin onto a wooden frame. Potential uses of the stem include the production of particle board and briquettes from waste material from furniture making. The leaves have been used as a thatching material in Sierra Leone, Ghana and Nigeria.

The apical bud (palm heart) is eaten, sometimes even raw. The young shoots are eaten boiled and fried as a vegetable. The soft pith of young shoots is also eaten. Sap from the stem is potable.

In Côte d’Ivoire women eat the boiled apical bud with the leaves of Caesalpinia bonduc (L.) Roxb. for the treatment of sterility-provoking stomach-ache. The soft pith of young shoots and a tea made from the young shoots are used against worms. In Cameroon an infusion of the leaves is taken against stomach-ache and dysmenorrhoea, the young shoots are a remedy against fever and dysentery and the sap is a vermifuge. In Cameroon and Congo the fresh stem is part of a preparation externally applied on dermatoses.

Production and international trade

Laccosperma secundiflorum is important both at subsistence level and for commercial utilisation. Its unit of trade is the ‘packet’. A packet of Laccosperma secundiflorum represents twenty stems, with each stem being 3–4 m long. The international rattan trade dates back as far as the 1920s, when Ghana supplied a significant proportion to the UK market. Some raw cane has been recently exported from Ghana and Nigeria to Korea. Currently, the international trade in rattan is worth about US$ 6.5 billion a year, but the international trade is dominated by South-East Asian countries.

Properties

The stem is reddish brown and is of light to medium weight with a density of 400–600 kg/m³ when oven-dry. It is valued because of its strength, durability, bending ability and aesthetic value. At 12% moisture content stems from Nigeria had a modulus of rupture of 91 N/mm² and a modulus of elasticity of 11,100 N/mm². It is common to see cracks on the stem surface. These cracks, which are areas of insipient structural failure, are attributed to different drying rates of the core and the outer portions. Furthermore, radial swelling and shrinking is higher than longitudinal swelling and shrinking, which may cause stresses within the cane leading to cracks and warping.

The stems are susceptible to discoloration by fungi, while beetles may make holes. The most common cause of staining are blue stain fungi. It is estimated that about 20% of harvested canes become stained if not treated. Fungal invasion can occur within one day of cutting. Staining can be controlled by spraying or soaking in preservative solution, but prophylactic treatment is seldom applied within 24 hours as required because of difficulties posed by harvesting procedures, storage and transport. Through intensive marketing, furniture in various colours has become fashionable. However, heavily stained material cannot be used for furniture since its bending strength is reduced; it is often utilized for baskets and other perishable products, or even as fuel. Poles can also be discoloured by surface moulds if transported or stored under humid conditions. Unlike blue stain, this discoloration is only superficial and can be wiped off. Nevertheless, the surface shine is reduced. At moisture levels of more than 20%, decay fungi can also attack the stem. Such infections are often noticed only at a later stage, when the fruit bodies appear, and they can cause serious structural degradation of rattan in service.

Air-dried samples of the stems in Nigeria were recorded to contain per 100 g: water 15.8 g, energy 1359 kJ (325 kcal), protein 2.9 g, fat 0.8 g, carbohydrate 79.4 g, ash 1.0 g, Ca 212 mg, Mg 35 mg.

Adulterations and substitutes

The stems of Laccosperma robustum (Burret) J.Dransf. have roughly the same properties as those of Laccosperma secundiflorum, and can be used for the same purposes. In Ghana, small diameter bamboos are sometimes used to make cane furniture frames.

Description

Moderately sized to robust, clustering rattan palm; stem 25–50 m long, 20–25 mm in diameter without sheaths, 30–35 mm in diameter with sheaths, internodes 10–50 cm long. Leaves sturdy, pinnately compound, up to 3.5(–5) m long; sheath dark green, armed with conspicuous brown to greenish sharp spines; ocrea 25–35 cm long and often torn at the margins, armed as sheath; petiole 20–60 cm long, rounded abaxially, concave adaxially, armed with black-tipped spines up to 18 mm long; rachis up to 1.5 m long, armed as petiole, distally prolonged into cirrus up to 2 m long, armed on the underside with black-tipped spines and bearing pairs of acanthophylls (leaflets modified into reflexed hooks) up to 4 cm long; leaflets up to 50 on each side of the rachis, elongate, often sigmoid but sometimes linear to lanceolate in shape, composed of 2–4 folds, 35–45(–60) cm × 2–8 cm, finely acuminate at the apex, dark green, margin armed with black-tipped spines 1–2 mm long. Inflorescence axillary, large, aggregate, branched to 2 orders; rachis branches 25–30 cm long, perpendicular to main axis; rachillae 15–20 cm long, pendulous; peduncle 15–20 cm long. Flowers bisexual, 2(–3) together, greenish white; calyx stalk-like at base, c. 8 mm long, with 3 triangular lobes c. 4.5 mm long; corolla c. 9 mm long, tubular at the base, with 3 valvate lobes; stamens 6; gynoecium 3-carpellate. Fruit ovoid, up to 2 cm × 1.5 cm, with 18–22 vertical rows of scales, reddish. Seed ovoid, 10–12 mm × 8–12 mm × 5–7 mm, often flattened on one side.

Other botanical information

Laccosperma comprises 6 species and is restricted to Africa. Although most species can easily be distinguished using vegetative characters, different species may bear similar vernacular names. Hence misidentification is common.

Laccosperma acutiflorum (Becc.) J.Dransf. (synonym: Ancistrophyllum acutiflorum Becc.) is a robust rattan with stems up to 70 m long and 35–60 mm in diameter (45–80 mm with sheaths), distributed from Sierra Leone to Gabon and DR Congo. Its stem is reported to be of very poor quality and therefore it is only occasionally used.

Laccosperma laeve (G.Mann & H.Wendl.) H.Wendl. (synonym: Calamus laevis G.Mann & H.Wendl.) is an understorey rattan with stems 10–13 m long and up to 16 mm in diameter (up to 20 mm with sheaths), leaflets with spineless margins, and coffee bean-like seeds, distributed from Liberia to Cabinda (Angola). It is occasionally used for basketry or weaving, and in Gabon the pounded stems are woven into rope. The roasted root is eaten to improve virility.

Laccosperma opacum (G.Mann & H.Wendl.) Drude (synonym: Ancistrophyllum opacum (G.Mann & H.Wendl.) Drude) is an understorey rattan with stems 10–15 m long and up to 15 mm in diameter (20 mm with sheaths), globose fruits and warty seeds. It is distributed from Liberia to eastern DR Congo and perhaps Uganda. In Ghana the split stem is sometimes used for making baskets, and the leaves are used for thatching. Sap from cut stems is drunk, and the roasted palm heart is eaten. In Cameroon decoctions of the stems are used for the treatment of cough, rheumatism and fractures.

Laccosperma robustum (Burret) J.Dransf. (synonym: Ancistrophyllum robustum Burret) is a robust rattan with stems 30–45 m long and 30–50 mm in diameter (45–60 mm with sheaths), and pendulous leaflets. It is distributed from Nigeria to eastern DR Congo and Cabinda (Angola). The whole stem is used for furniture frames, and the split stems are used for coarse basketry. It is highly prized and much traded.

Anatomy

The cross section of the stem shows three distinct regions: epidermis, cortex and central cylinder. The epidermis consists of a single layer of approximately square cells with a radial length of 11.6–19 μm and width of 8.7–14.5 μm. The cortex consists of fibre bands, rudimentary vascular bundles embedded in parenchyma cells, lying ring-like around the central cylinder. The cortex is 80–823 μm wide, with parenchyma cells round, oval and occasionally radially elongated, of varying sizes; intercellular spaces are present. There are two fibre rows just below the epidermis. The central cylinder is composed of vascular bundles embedded in ground parenchyma. The peripheral vascular bundles are larger and arranged in a patch-work-like manner; the inner ones are smaller and diffusely scattered. The vascular bundles consist of conducting tissue (xylem and phloem), surrounded by a fibre sheath and parenchyma. In a complete vascular bundle there is one metaxylem vessel with a diameter of 175–375 μm, the protoxylem consists of a cluster of 1–6 vessels, and the phloem occurs in a single field containing a cluster of 4–10 sieve tubes. The surrounding fibre sheath is more extensive in peripheral vascular bundles than in inner vascular bundles, which are horse shoe-shaped in cross-section. The fibre cells are 0.4–6.7 mm long and 7.3–43.5 μm wide, with a lumen width of 0.3–26 μm and a cell wall thickness of 2.9–37.7 μm. The ground tissue parenchyma, round to oval in shape and sometimes radially elongated (rectangular), is arranged in a net-like pattern.

Growth and development

Laccosperma secundiflorum grows rapidly. In Cameroon an annual extension growth of about 2.8 m has been recorded for seedlings planted under obsolete rubber trees. Flowering is predominantly during the rainy season, and fruiting in the dry season. Laccosperma secundiflorum is hapaxanthic, which means that individual stems die after flowering. The seeds are dispersed primarily by birds (especially hornbills). However, primates, predominantly drills and mandrills (two species of forest primate related to the baboon), chimpanzees and gorillas are also key dispersal agents, as are elephants. Predation by rodents accounts for some additional dispersal.

Ecology

Laccosperma secundiflorum occurs up to 1050 m altitude in high forest, rarely in secondary forest. It is particularly abundant in seasonally inundated and swampy areas. It grows well in poorly drained waterlogged soils in areas where the average annual rainfall is below 1600 mm. In areas with an average annual rainfall over 1750 mm, however, it prefers well-drained locations. The species prefers gaps in dense high forest, and it benefits from a certain amount of forest disturbance. The rootstock is easily killed by fire and it will not regenerate in areas that have been burnt several times in the past.

Propagation and planting

Laccosperma secundiflorum can be propagated with seed or vegetatively using rhizomes or suckers. Seed propagation is more common since it is difficult to gather large quantities of suckers or rhizomes due to their bulkiness. However, seed germination is slow and seed mortality high. In trials in Cameroon emergence took as long as 100 days, with a germination rate of only 19%. This may be due to the seed having a relatively robust seed coat, which impedes imbibition, causing a dormancy that can delay germination for 9–12 months. In trials in Cameroon, the average time from planting to shoot emergence was 74 days for suckers and 84 days for rhizomes. In a trial in Côte d’Ivoire shoots emerged from suckers 35–56 days after planting, but shoots did not develop from rhizomes.

In-vitro propagation using axillary bud and apical meristem explants has proven possible, but for mass propagation the reliability and efficiency of the protocol need to be improved.

Management

Laccosperma secundiflorum is harvested exclusively from the wild. Usually cutting of all the stems within a clump prevents juvenile ones from growing successfully, since their survival depends on the mature stems in the middle of the clumps. To ensure sustainability, only mature stems should be removed and adequate light should be made available to the juvenile ones to ensure vigorous regeneration. Where some level of management of wild Laccosperma secundiflorum is implemented, the cut stems are almost totally removed to deliberately allow adequate light penetration for regeneration of the clump. The same clump can then be harvested again 3–5 years later. Some clumps are known to have been harvested more than 4 times.

In on-farm trials in Ghana, Nigeria and Cameroon high post planting mortalities were recorded, which were attributed to neglect and predation by rodents. However, the growth rates reported in established plantings in West Africa were encouraging, which indicates that, once past the establishment phase, Laccosperma secundiflorum can be grown in a relatively short cropping cycle.

Diseases and pests

Laccosperma secundiflorum is susceptible to attacks by fungi and insects due to its high starch content. Defects resulting from these attacks can result in severe losses.

Harvesting

From each rattan clump, harvesters tend to cut only the mature canes; young stems are often left and can be harvested during a later visit. The stems selected are those with no lower leaves, and often only the lower 6 m (2 lengths of cane) are harvested. This is because living nodes form a considerable obstruction when the cane is split. So, the remaining 30 m of each mature stem is left in the canopy, and previously harvested rattan clumps are often marked by the presence of many dry stems in the canopy. The major disadvantage of this harvesting procedure is that, with the top sections of the cut stems remaining in place, there is little light penetration to the clump. This often means that the rhizome will not regenerate, and the clump often dies. In some communities improved harvesting is practiced, mainly with the aim of encouraging regeneration after harvest. In this case, the main part of the cut stems is removed from the canopy to allow sufficient light to reach the rhizome. Harvesting of rattans is often an unpleasant and dangerous occupation with dead branches being dislodged from the canopy, as well as ants and wasps being disturbed.

Yield

Laccosperma secundiflorum and other rattans occur widely dispersed and therefore no reliable data on yield per unit area of forest are available.

Handling after harvest

Freshly harvested canes should be treated shortly after harvesting, before transportation or usage, to reduce their weight and their susceptibility to attacks by fungi and insects. After being harvested, the stems are arranged into bundles and head-portered to local villages. Carrying these heavy bundles from far inside the forest makes for strenuous work. Afterwards, drying is undertaken in the open air with little or no preservative treatment. Other post-harvest treatments, including oil curing, bleaching, deglazing to remove the silicified epidermis and fumigation, are necessary to avoid defects and to increase processing possibilities and market value.

Genetic resources

Laccosperma secundiflorum has a wide distribution and is not considered threatened, according to IUCN criteria. However, the demand for cane has increased over the years, and there is now a threat to the populations that are easily accessible.

Prospects

The demand for Laccosperma secundiflorum is increasing, and in many parts of Africa much more is being processed today than five or ten years ago. The increased demand has led to a significant decline in wild stocks and considerable local scarcity, particularly around urban centres. Although the establishment of cultivation systems for the species seems useful for the rattan cottage industry in Africa, there appears to be little adoption among farmers, mainly because of land tenure issues and the relative abundance of rattans in the wild.

Major references

  • Abbiw, D.K., 1990. Useful plants of Ghana: West African uses of wild and cultivated plants. Intermediate Technology Publications, London and Royal Botanic Gardens, Kew, Richmond, United Kingdom. 337 pp.
  • Burkill, H.M., 1997. The useful plants of West Tropical Africa. 2nd Edition. Volume 4, Families M–R. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 969 pp.
  • Defo, L., 2004. Rattan exploitation in the Yaounde region of Cameroon. In: Sunderland, T. & Ndoye, O. (Editors). Forest Products, livelihoods and conservation. Case studies of non-timber forest product systems. Volume 2, Africa. CIFOR, Bogor, Indonesia. pp. 291–316.
  • Ebanyenle, E. & Oteng-Amoako, A.A., 2003. Anatomy and identification of five indigenous rattan species of Ghana. Ghana Journal of Forestry 11(2): 77–90.
  • Oteng-Amoako, A.A. & Obiri-Darko, B., 2002. Rattan as a sustainable cottage industry in Ghana: the need for development interventions. In: Sunderland, T.C.H. & Profizi, J.P. (Editors). New research on African rattans. Proceedings of the CARPE-funded International Expert Meeting on the Rattans of Africa, held at the Limbe Botanic Garden, Cameroon, 1–3 February 2000. International Network for Bamboo and Rattan (INBAR), Beijing, China. pp. 105–114.
  • Profizi, J.P., 1986. Notes on West African rattans. RIC Bulletin 5(1): 1–3.
  • Sunderland, T.C.H., 2007. Field guide to the rattan palms of Africa. Kew Publishing, Royal Botanic Gardens, Kew, Richmond, United Kingdom. 66 pp.
  • Sunderland, T.C.H., Balinga, M.P.B., Asaha, S. & Malleson, R., 2008. The utilization and management of African rattans: constraints to sustainable supply through cultivation. Forests, Trees and Livelihoods 38(4): 337–353.
  • Sunderland, T.C.H., Beligné, V., Bonnéhin, L., Ebanyenle, E., Oteng-Amoako, A. & Zouzou, E.-J., 2005. Taxonomy, population dynamics and utilisation of the rattan palms of the Upper Guinea forests of West Africa. In: Bongers, F., Parren, M.P.E. & Traoré, D. (Editors). Forest climbing plants of West Africa. Diversity, ecology and management. CABI Publishing, Wallingford, United Kingdom. pp. 147–166.
  • Tuley, P., 1995. The palms of Africa. The Trendrine Press, St. Ives, United Kingdom. 189 pp.

Other references

  • Abbiw, D.K., 1997. Traditional vegetables in Ghana. In: Guarino, L. (Editor). Traditional African vegetables. Proceedings of the IPGRI international workshop on genetic resources of traditional vegetables in Africa: conservation and use, 29–31 August 1995, ICRAF, Nairobi, Kenya. Promoting the conservation and use of underutilized and neglected crops 16. pp. 29–38.
  • Adjanohoun, E.J., Ahyi, A.M.R., Aké Assi, L., Baniakina, J., Chibon, P., Cusset, G., Doulou, V., Enzanza, A., Eymé, J., Goudoté, E., Keita, A., Mbemba, C., Mollet, J., Moutsamboté, J.-M., Mpati, J. & Sita, P. (Editors), 1988. Médecine traditionnelle et pharmacopée - Contribution aux études ethnobotaniques et floristiques en République Populaire du Congo. Agence de Coopération Culturelle et Technique, Paris, France. 606 pp.
  • Blach-Overgaard, A., Svenning, J.-C., Dransfield, J., Greve, M. & Balslev, H., 2010. Determinants of palm species distributions across Africa: the relative roles of climate, non-climatic environmental factors, and spatial constraints. Ecography 33(2): 380–391.
  • Defo, L., 1999. Rattan or porcupine? Benefits and limitations of a high-value NWFP for conservation in the Yaounde region of Cameroon. In: Sunderland, T.C.H., Clark, L.E. & Vantomme, P. (Editors). Non-wood forest products of Central Africa: current research issues and prospects for conservation and development. Food and Agriculture Organisation, Rome, Italy. pp. 237–244.
  • Ebanyenle, E. & Oteng-Amoako, A.A., 2005. Variation in some anatomical and physical properties of stems of five rattan palm species of Ghana. Journal of Bamboo and Rattan 4(2): 125–142.
  • Irvine, F.R., 1961. Woody plants of Ghana, with special reference to their uses. Oxford University Press, London, United Kingdom. 868 pp.
  • Jiofack, T., Fokunang, C., Guedje, V., Kemeuze, V., Fongnzossie, E., Nkongmeneck, B.A., Mapongmetsem, P.M. & Tsabang, N., 2009. Ethnobotanical uses of some plants of two ethnoecological regions of Cameroon. African Journal of Pharmacy and Pharmacology 3(13): 664–684.
  • Kouakou, K.L., Zoro Bi, I.A., Abessika, Y.G., Kouakou, T.H. & Baudoin, J.-P., 2009. Rapid seedlings regeneration from seeds and vegetative propagation with sucker and rhizome of Eremospatha macrocarpa (Mann & Wendl.) and Laccosperma secundiflorum (P.Beauv.) Kuntze. Scientia Horticulturae 120: 257–263.
  • Kouakou, K.L., Zoro Bi, I.A., Kouakou, T.H., Koné, M. & Baudoin, J.-P., 2009. Direct regeneration of rattan seedlings from apical meristem and axillary bud explants. Belgian Journal of Botany 142(1): 60–67.
  • Kouassi, K.I., Barot, S., Gignoux, J. & Zoro Bi, I.A., 2008. Demography and life history of two rattan species, Eremospatha macrocarpa and Laccosperma secundiflorum, in Cote d’Ivoire. Journal of Tropical Ecology 24: 493–503.
  • Lucas, E.B. & Dahunsi, B.I.O., 2004. Characteristics of three western Nigerian rattan species in relation to their utilization as construction material. Journal of Bamboo and Rattan 3(1): 45–56.
  • Mohanan, C., 1993. Biodeterioration of post-harvest rattans. In: Rattan management and utilization. Proceedings of a seminar, Trichur, India, 1992. Kerala Forest Research Institute, Peechi, India. pp. 266–280.
  • Morakinyo, A.B., 1995. The commercial rattan trade in Nigeria forests. Trees and People Newsletter 25: 22–30.
  • Olorunnisola, A.O., 2004. Briquetting of rattan furniture waste. Journal of Bamboo and Rattan 3(2): 139–149.
  • Olorunnisola, A.O., Pitman, A. & Mansfield-William, H., 2005. Strength properties and potential uses of rattan-cement composites. Journal of Bamboo and Rattan 4(4): 343–352.
  • Sunderland, T.C.H., 2001. The taxonomy, ecology and utilisation of African rattans (Palmae: Calamoideae). PhD Thesis, University College, London, United Kingdom. 359 pp.
  • Sunderland, T.C.H., Defo, L., Ndam, N., Dione, M. & Tamnjong, I., 2003. A socio-economic profile of the rattan trade in Cameroon. In: Sunderland, T.C.H. & Profizi, J.P. (Editors). New research on African rattans. Proceedings of the CARPE-funded International Expert Meeting on the Rattans of Africa, held at the Limbe Botanic Garden, Cameroon, 1–3 February 2000. International Network for Bamboo and Rattan (INBAR), Beijing, China. pp. 115–140.
  • Tshiamala-Tshibangu, N., Gbeli, Essimbi, E.P. & Ndjigba, J.D., 1999. Utilisation des produits forestiers autres que le bois (PFAB) au Cameroun : cas du projet forestier du Mont Koupé. Revue de Médecines et Pharmacopées Africaines 13: 19–32.
  • Vanden Berghen, C., 1988. Flore illustrée du Sénégal. Monocotylédones et Ptéridophytes. Volume 9. Monocotylédones: Agavacées à Orchidacées. Gouvernement du Sénégal, Ministère du Développement Rural et de l’Hydraulique, Direction des Eaux et Forêts, Dakar, Senegal. 522 pp.
  • Zoro Bi, I.A. & Kouakou, K.L., 2004. Vegetative propagation methods adapted to two rattan species Laccosperma laeve and Laccosperma secundiflorum. Tropicultura 22(4): 163–167.

Sources of illustration

  • Sunderland, T.C.H., 2001. The taxonomy, ecology and utilisation of African rattans (Palmae: Calamoideae). PhD Thesis, University College, London, United Kingdom. 359 pp.

Author(s)

  • E. Opuni-Frimpong

Forestry Research Institute of Ghana (FORIG), University P.O. Box 63, KNUST, Kumasi, Ghana

  • L.K. Kwakye Ameyaw

Forestry Research Institute of Ghana (FORIG), University P.O. Box 63, KNUST, Kumasi, Ghana

  • E. Ebanyenle, Forestry Research Institute of Ghana (FORIG), KNUST, University, P.O. Box 63, Kumasi, Ghana
  • T.C.H. Sunderland, Forests and Livelihoods Programme, Centre for International Forestry Research (CIFOR), P.O. Box 0113 BOBCD, Bogor 16000, Indonesia

Correct citation of this article

Opuni-Frimpong, E. & Kwakye Ameyaw, L.K. & Ebanyenle, E. & Sunderland, T.C.H., 2011. Laccosperma secundiflorum (P.Beauv.) Küntze. [Internet] Record from PROTA4U. Brink, M. & Achigan-Dako, E.G. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. <http://www.prota4u.org/search.asp>.

Accessed 7 March 2020.