Peltophorum dasyrhachis (Miquel) Kurz
Family
Leguminosae
Synonyms
Caesalpinia dasyrhachis Miquel, Peltophorum grande Prain, Peltophorum tonkinense (Pierre) Gagnep.
Vernacular Names
|
Malaysia |
Batai, jemerelang. |
|
English |
Peltophorum. |
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Indonesia |
Soga (Palembang), petaian (Lampung). |
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Cambodia |
Trâse:k. |
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Laos |
S’a:z kha:m, sa: fang, sa: ph’ang. |
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Thailand |
Nonsi (centra!), arang (north-eastern). |
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Vietnam |
Lim x[ej]t, lim v[af]ng. |
Geographical Distributions
Peltophorum dasyrhachis is found in Thailand, Indo-China, Peninsular Malaysia, Sumatra and Borneo. It is also cultivated in many other tropical regions, e.g. in Java.
Description
Peltophorum dasyrhachis is usually a deciduous tree that can grow up to 30 m tall, with a straight trunk and rather diffuse crown. The root system is with a well-developed taproot and a few superficial lateral roots. Its trunk is up to 70 cm in diametre. The bark is up to 10 mm thick and reddish brown inside. The young branches are reddish-hairy.
The leaves are bipinnate, with 5-9 pairs of pinnae and 6-16 pairs of leaflets per pinna. The stipules are large, bipartite and with pinnatifid or bipinnatifid branches. The petiole is up to 7 cm long. The rachis is up to 40 cm long. Both petiole and rachis are reddish-pubescent. The leaflets are oblong-elliptical, measuring 10-25 mm x 4-10 mm, sessile, acute at base, obtuse or rounded, rounded-emarginate at apex, finely pubescent, nearly hairy, rather glaucous below and shiny above.
The inflorescence is an axillary with unbranched raceme and measures 15-30 cm long. The bracts are linear, measure 10-12 mm long and persisting until the flowers open. The pedicel is 1.7-4 cm long. The sepal is deeply 5-lobed. The lobes are ovate, measuring 10-15 mm x 5-6 mm, densely velvety outside and hairless inside. There are 5 obovate petals which measure 15-25 mm x 10-12 mm, spreading, yellow and hairy towards the base inside. There are 10 free stamens. The filaments are 10-15 mm long and woolly at the base. The anthers are dorsifixed.
The ovary is sessile. It is 5 mm long, hairy, 4-8-ovuled and with slender style. The pod is elliptical, sharp-pointed, measuring 10-15 cm x 2–4 cm, flat and dull-brown when ripens but blackish later. It is 4-8-seeded, indehiscent and often hanging in bunches below the leaves. The seed is flattened oblongoid, measuring 10-12 mm x 5 mm and transversely positioned. Seedling is with epigeal germination. The hypocotyl is 4-6 cm long. The cotyledons are stalked, 3 nerved and smooth.
Ecology / Cultivation
Peltophorum dasyrhachis is found in secondary, deciduous or evergreen forests below 800 m altitude with an annual rainfall of 1500-2500 mm. It is mainly found on ultisols. Due to its relatively deep rooting system, it is drought tolerant. Its hairiness and fairly thick bark have been associated with its tolerance of fire.
Line Drawing / Photograph
References
1. Plant Resources of South-East Asia No.11: Auxiliary plants.
