Calamus poilanei

Calamus (KAL-ah-muhs) poilanei (poh-ee-LAHN-eh)
Nam Theun Dam, Laos. Photo by Dr. John Dransfield, Royal Botanic Gardens, Kew/Palmweb.
Scientific Classification
Genus: Calamus (KAL-ah-muhs) Species: poilanei (poh-ee-LAHN-eh)
Synonyms
None set.
Native Continent
Asia
Morphology
Habit: Solitary Leaf type: Pinnate
Culture
Survivability index
Common names
wai thoon (Lao Loum), blong thoon (Khamu), gaparl (Phong), wai kruh (Thailand), probably also wai khom (Lao Loum), blong chang (Khamu), wai nampung (Thailand).

Habitat and Distribution

Indochinese endemic, Thailand (North and North-east), Laos (Central and North) and Vietnam (South Annam and

Nam Theun Dam, Laos. Photo by Dr. John Dransfield, Royal Botanic Gardens, Kew/Palmweb.

probably North Annam). Tropical moist forest. In Laos at 300 - 1300 m, in Thailand at 600 - 700 and in South Annam at 500 m.

Description

Robust single-stemmed rattan. Stem climbing to 150 m long, but usually much less because of over-harvesting, without sheaths 3–5 cm in diam., with sheaths 4–7.5 cm in diam., internodes about 35 cm long, longer in juvenile stems. Leaves ecirrate, massive; sheaths bright green, sometimes with scattered dark brown indumentum, armed with scattered, solitary or occasionally paired, reflexed broad triangular green spines 1.5–3.5 cm long, with black tips and slightly swollen bases, spines sometimes very sparse or lacking altogether; ocrea inconspicuous, very short, tattering, bearing scattered black caducous indumentum; knee prominent, generally unarmed; flagellum massive, often exceeding 7 m long; petiole to 60 cm long, about 2.5 cm wide, armed with scattered groups of broad triangular spines to 1.5 x 0.4 cm; rachis to 2.25 m, somewhat curved, bearing about 40, regularly arranged leaflets on each side of the rachis, the longest to 55 x 3 cm, armed with scattered short black spines along the margins and two lateral nerves on upper surface. Inflorescences 2–6 m or more long with a terminal flagellum and numerous (10 or more) widely spaced partial inflorescnces, the male branched to 3 orders the female to 2; male rachillae 3 x 0.4 cm, female rachillae 11–20 x 0.4 cm. Mature fruit ovoid, 2.0 x 1.4 cm, covered in about 20 rows of pale straw-coloured spines with darker margins. Seed ellipsoid with flattened side, about 1.2 x 0.8 cm; endosperm homogeneous. (J. Dransfield, A Synopsis of the Rattans (Arecaceae: Calamoideae) of Laos and Neighbouring Parts of Indochina. 2002)/Palmweb. Editing by edric.

Comments and Curiosities

Uses: Calamus poilanei is the most economically important rattan in Laos, dominating the export trade in raw cane and being the preferred species used by Lao artisans for the frames of furniture. The shoot is also edible. There are plantations extent in Vietnam.

Conservation: Of high conservation concern. Listed as Threatened- Rare in Vietnam (Phan Thuc Vat 1996). Although relatively widespread within Indochina, high harvesting pressure has already caused the collapse of many populations (e.g. in Laos, pers. obs.) and declines are undoubtedly continuing. Stem harvesting is the main threat, but shoot harvesting may threaten some remnant populations. The solitary habit hinders regeneration and harvests have been so thorough in many areas that very few mature fruiting stems remain.