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Calamus solitarius T. Evans et al vai thork

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Calamus solitarius T. Evans et al. vai thork

Synonyms: C. oligostachys T. evans et al., C. tetradactylus Hance.

Other names: Local name: vai yong, vai hakyong, vai savang.

Use: Local people use canes for handicrafts like baskets, mats, knife handles, hunting and fishing tools. In factories canes are used to make frame structures for furniture or weave seats. Shoots are a common food but some species taste a little bitter and are often not used.
Active ingredients:
Harvesting of canes of both mature and immature stems mostly takes place in the dry season. Cane collection is often done by the poorest families, but harvesting depends on the orders from factory or middleman, who have to request for quotas. Small caned rattans are completedly harvested, and cut at 4-10 m long to facilitate transport from the forest, however sizes harvested depend also on the demand. Gatherers are able to haul 50 kg of canes. Young shoots (up to 12 months) are harvested for eating, mostly in the rainy season. Shoots are cut of ca. 1 m long. One person is able to carry about 70 shoots (ca. 50 cm long) collected within half a day. Villagers would be able to cut more, but loads would then be too heavy.
Yield: Between 20-50 stems per ha.
Access rules: Because of policy restrictions harvesting of quality rattan is not officially promoted, but in general is considered to be village common property and most rattans are collected from the wild under a system of free access. Conservation areas are frequently encroached upon for illegal rattan collection. Community management rules and commencement dates for sustainable harvesting of natural stands are sometimes set up.
Sustainability: The practices used to harvest rattan from natural stands are destructive, as both mature and immature stems are cut and only mature stems (5-20 years) carrying fruits. For solitary stemmed rattans regeneration is poor as shoots can only be harvested once, after which the plant dies and less seed is available. National programmes of land allocation, management around protected areas and improving rural education may all help to avoid rattans being completely over-harvested in most areas. Also more research is required to study domestication and harvesting of rattans, with some small trial plantations at Nam Xuang, Vientiane.
Conservation status: Most forest outside protected areas will probably be cleared or have rattans over-harvested in the future, and protected areas will be the main gene pool and for conservation of rattans.
Processing: For eating the shoots, the spiny bark is removed and the inner core of the plant cooked or roasted, which tastes like bamboo-shoots or asparagus. Canes are mainly exported as raw material, with a limited amount of small rattan furniture manufacturers in Vientiane, Savannaketh and Pakse, producing for the local market. Production of rattan handicrafts is often done by richer villages who buy rattan from poorer villages. Villagers mature raw canes by sun drying or smoking causing scorching and quality loss. Canes are split and cut to different sizes for the making of handicrafts and, small furniture. For thatching purposes, mature leaflets are woven. In many cases traders or middle-men bring designs popular in urbans markets to be copied in the village. Factories boil the canes in diesel solutions for 10-30 minutes at 60-150°C to remove moisture, waxy materials, resins and gums, to improve colour and prevent insect or fungi attack. After boiling canes are washed with pressured water or scrubbed with sawdust to remove remaining dirt and excessive diesel. Sulphur is used to provide a uniform colour of the canes. For the removal of stains a bleaching solution of 1% hydrogen peroxide and a 1:4 ratio of sodium hydroxide : sodium silicate is used at a temperature of 60°C for 2 hours. Subsequently canes are air-dried for a period of 50-60 days, while checked and shaken. After this they are straightened and tied in bundles of 30-60 kg. During this time rattan canes are sorted and graded. Before bending canes for large furniture into desired shapes, they are heated by steam to facilitate bending in moulds.
Quality criteria: Grading is based on defects. To avoid this, canes should be kept from the ground, to avoid fungi and dirt damage.

Marketing: Locally a single bitter shoot is sold for US$0.05-0.07. Factories or middlemen buy canes from farmers for ca. US$0.5-0.6/kg. Different standard sizes for selling canes are:



5 m long


Diameter in mm, per kg






Market prospects: There may be a potential for developing rattan furniture industry, but requires improved designs and good connections to overseas markets, which are difficult to establish for small farmers. Companies have shifted from large diameters to small diameters for canes and some believe they cannot maintain the business for much longer, with resources being depleted. The trade in edible rattan shoots from wild plants is large but essentially unregulated. Rattan plantation development is under way in the country, and edible shoot production is a dynamically growing subsector. The outlook for expanding edible shoot production is much better than that for cane production, as rattans are now grown in open sun with no available climbing supports. However, abundance of cheap seedlings and widespread expertise in growing these species will make cane plantations easier to establish if economic conditions become attractive in the future. There is a large domestic market, and the Laos competes only with Thailand in supplying the export market with exports of semi-processed and processed rattan canes still increasing to Thailand, China and Vietnam but prices are unstable.
Propagation: Rattans can be planted from seed, but need assistance in germination, otherwise this will take 1 year: skins and pulp are removed from the seeds, then soaked in water and dried in the sun. Young seedlings are planted in bags, germinating starting after (15)20-30 days and transplanted after 1 year. Growth is slow in the first 5 years, after that faster. Edible shoots can be harvested when plants are 3-4 years old. Small diameter rattans take 10-15 years to grow to mature sizes. Propagation is also possible by culms or rhizomes, and tissue culture, mainly carried out in Thailand and Malaysia. It is better to plant rattan from seed than by digging seedlings form the forests, often resulting in high mortality rates.
Description: Solitary, stem up to 50 m long or more and 0.4-1 cm diameter. Sheath 0.6-1.5 cm diameter, dark or pale green with some grey-brown indumentum. The roots often form stilts raising the base of the stem off the ground. Ocrea tiny, dry, with no spines or bristles. Leaf 0.5-1 m long, leaflets in group, petiole 2-10 cm long. Inflorescence 1.3-5 m long plus flagellum. Fruit 0.8 by 0.8 cm, scale pale yellow when dry with reddish margins, perianth remains partly tubular, seed not ruminate.

Distribution & Ecology: Vai thork grows in evergreen or semi-evergreen forest, including in areas with much bamboo, at 200-600 m. Found in Vientiane, Bolikhamxay and Khammouane provinces.


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