Calamus simplicifolius (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Calamus simplicifolius Wei

Protologue: Guihaia 6(1/2): 36 (1986).

Family: Palmae

Chromosome number: 2n= unknown

Vernacular names

• China: danye shengteng (Hainan).

Origin and geographic distribution

C. simplicifolius is found on Hainan Island. It has been introduced for cultivation trials in southern China.

Uses

C. simplicifolius is the best Chinese cane of medium diameter, supreme for all types of binding and weaving in the furniture industry and widely used locally for cordage, house construction and the finest basketware when it is abundant. New shoots can be eaten as a vegetable.

Production and international trade

The canes are collected wherever they occur because of their high economic value. Due to its restricted distribution, production occurs only in a few places and no reliable figures are available on annual output. After harvesting the canes are sold to middlemen and then shipped to manufacturers in cities on the mainland for making furniture and handicrafts.

Properties

C. simplicifolius has excellent appearance with its creamy yellow colour and highly glossy surface. Its uniform texture makes it particularly suited to being split into strips or being used whole for furniture making. Specific gravity is 0.488. Tensile strength is 51.2 N/mm². Lignin content is 20%. One seed weighs 0.8 g.

Description

Clustering, rarely forming dense clumps, moderatesized dioecious rattan, climbing high into canopy, with stems ultimately up to 50 m long. Stem without leafsheaths 1215 mm in diameter, with sheaths 50 mm in diameter; internodes c. 30 cm long. Whole leaf up to 3 m long; leafsheath yellowishgreen, armed with flattened triangular spines 2040 mm long and 58 mm wide at the base; knee conspicuous; ocrea conspicuous, purplish, glabrous; petiole up to 20 cm in juveniles, very short in adults; leafrachis bearing scattered spines on the lower surface, distally the rachis prolonged into a whip (cirrus) up to 1.5 m long, bearing grapnellike groups of reflexed spines; leaflets c. 22 on each side of the rachis, arranged irregularly, usually solitary, but sometimes 24 leaflets grouped, lanceolate, up to 40 cm×5 cm, with 5 major veins. Inflorescence borne on the sheath of the leaf above the subtending axil, to 1 m long, the male and female superficially similar, the male branching to 3 orders, the female to 2; bracts tightly tubular; flowerbearing branches to 4.5 cm long, with c. 20 flowers; male flower ovoid to oblong, c. 7.5 mm long, calyx to c. 4.5 mm; female flowers not recorded. Mature fruit 1seeded, spherical, c. 25 mm×20 mm, with a beak to 3 mm long, covered in 18 vertical rows of neat reflexed yellowishwhite scales. Seed ovoid to oblong, c. 13 mm×12 mm, with an outer fleshy sarcotesta; endosperm very deeply ruminate; hilum concave; embryo basal. Seedlingleaf bifid.

Cane anatomy The epidermal zone is built up of one layer of rectangular, silicified cells, and the subepidermal zone of 34 layers of lignified parenchyma cells. The vascular bundle density is 46 /mm². The length of fibres in outer zone and bark is 1.5 mm and 1.4 mm respectively.

Growth and development

Seed germinates 5060 days after sowing with a few seeds germinating after 120 days; after 23 months the seedlingleaf emerges; after 3 years, the first stem may exceed 1 m long, the first climbing whips are produced and 12 suckers in a clump may appear from very short horizontal rhizomes. Three to four years after establishment, the stem may grow at rates exceeding 2.02.5 m/year under suitable conditions. At 10 years old, a clump may consist of 12 aerial stems. Flowering begins in the 5th year after sowing, and is annual thereafter. Phenological cycle has little variability from place to place; generally inflorescences emerge in August, flower buds from February to March of the following year, anthesis starts in April, peaks in May and ends in June when fruiting begins; fruit maturation starts in late October, peaks in November and ends in early December.

In humid rain forest, its prime habitat, only one of the stems in a clump, rarely two, grows up to be a long aerial stem, reaching the forest canopy. Knowledge of the basic biology of this rattan is limited.

Other botanical information

The closely related C. egregius Burret differs from C. simplicifolius in the arrangement of the leaflets, which, in C. egregius occur in pairs or groups of 34.

Ecology

It is usually found growing in natural mountain rain forest between 6001100 m altitude. For optimum growth, C. simplicifolius as well as C. egregius, prefers moisture in abundance and adequate light. The annual average growth rate of the stems growing under semishade canopy conditions is 3 times as high as that of stems growing in dense forest. However, young seedlings cannot withstand full sunlight throughout the day as young leaves may become scorched. Young leaves and new shoots may easily be damaged by temperatures of below2C.

Propagation and planting

C. simplicifolius can be propagated by sucker shoots but propagation is best effected from seeds. Seed propagation includes removing the fruit wall and fleshy seedcoat, cleaning the seeds, sowing seeds in sand beds for germination, and transporting the sprouted seed (the first foliage leaf unexpanded) in potting bags into a nursery under semishade. Seedlings 1115 months old and with 67 leaves are usually ready for planting out. Although seedlings require the support of preexisting tree crops and forest canopy, they also require adequate sunlight for healthy and fast growth. On a small scale, seedlings can be planted in scattered clumps in agroforestry systems; on a commercial scale the species can be planted in lines, on a grid of about 4 m×5 m in loggedover forests or in planted broadleaved forests but the forest canopy should be manipulated to allow light to reach the seedlings. Group planting, 23 seedlings per clump, is considered to be suitable for this species.

Husbandry

Planting lines have to be cleared and the forest canopy has to be thinned to allow sufficient light through to reach the seedlings in the first three years after planting. Fertilizer application may enhance seedling growth.

Diseases and pests

Leaf blight and leafspot diseases caused by fungi occur in poorly managed nurseries. So far, no serious pest problems have been reported, apart from rats attacking seedlings.

Harvesting

Harvesting is carried out in the wild by dragging the stem out of the canopy, removing of the leaves, leafsheaths and debris, cutting the cane into lengths of about 45 m, tying in bundles and transporting to the village for sale.

Yield

It is estimated that 1011 years after establishment the plantation will be ready for initial harvest, with an estimated yield of about 3.5 t/ha. It is also estimated that within a 25year management period, canes may be harvested 5 times in a rotation of 5 years, providing a total yield of about 11.5 t/ha.

Handling after harvest

This is usually carried out by middlemen in the processing village. The first steps involved in preliminary processing are cleaning and drying the canes to prevent attack by staining fungi and powderpost beetle and sorting according to length and quality. Further processing performed by manufacturers involves grading into size classes, rubbing, and splitting and coring into strips.

Genetic resources and breeding

C. simplicifolius has been planted in several botanic gardens and arboreta in southern China, but no attempt has been made to establish a collection to represent the considerable variation in the wild.

Prospects

C. simplicifolius has high commercial value. However, owing to its restricted distribution and severe overexploitation, it may soon be on the verge of extinction. The prospects for C. simplicifolius and the closely related C. egregius as cultivated crops are good. Because of its excellent quality and growth form, it has great potential to be planted not only in subtropical areas in southern China but also in the northern part of the Prosea region. On a small scale, it can be planted in agroforestry systems as a potential source of income for rural people.

Literature

• Cai, Z.M., 1989. Distribution of vascular tissue in four rattan canes. Acta Botanica Sinica 31(8): 569575.
• Rao, A.N. & Vongkaluang, I. (Editors), 1989. Recent research on rattans. Proceedings of the International Rattan Seminar, Chiangmai, 1214 November 1987. Faculty of Forestry, Kasetsart University, Thailand and International Development Research Centre, Canada. pp. 1318, 130137.
• Wei, C.F., 1986. A study on the genus Calamus of China. South China Institute of Botany, Academia Sinica 6(1/2): 1740.
• Xu, H.C., Zhou, Z.Z. & Yin, G.T., 1991. Nutrition evaluation of shoots of two rattan species. Rattan Information Centre Bulletin 10(4): 1720.
• Yin, G.T. & Xu, H.C., 1988. A preliminary study on the effect of different levels of light intensity on the growth of rattan seedlings. Forest Research 1(5): 548551.
• Zhou, Z.Z., Xu, H.C. & Yin, G.T., 1991. A financial appraisal of three commercial rattan plantations. Forest Research 5(1): 4755.

Authors

H.C. Xu & G.T. Yin