Erythrina subumbrans (Hassk.) Merrill

Erythrina subumbrans (Hassk.) Merrill

Family

Leguminosae

Synonyms

Erythrina lithosperma Miquel, Hypaphorus subumbrans Hassk., Erythrina hypaphorus Boerl.

Vernacular Names

Malay­sia                          

Dedap batik, cengkering.

English          

December tree.

Thailand       

Thonglang-pa (northern), thong-Iang (central).

Indonesia     

Dadap duri (general), dadap rangrang (Sun­danese), dadap ri (Javanese) (armed forms); da­dap minyak (general), dadap lesang (Sundanese), dadap lenga (Javanese) (thornless forms).

Philippines    

Dap-dap (Tagalog), rarang (Bikol), anii (Bisaya).

Myanmar       

Ye-katit.

Papua New Guinea          

Th'o:ng hla:ng.

Geographical Distributions

Erythrina sub­umbrans occurs naturally from India and Sri Lan­ka, throughout Southeast Asia (except New Guinea) to Fiji and Samoa. Now, it is distributed throughout the tropics.

Description

Erythrina sub­umbrans is a deciduous, medium-sized tree which can reach 5-25 m tall while its trunk can reach up to 60 cm in diameter. The crown spreads and the bark is whitish. The trunk and branch­es are armed with stout prickles while in cultivation, it is mostly unarmed.

The leaves are arranged alternate and with three leaflets. The stipules are orbicular, small and caducous. The rachis is 10-21 cm long and inclusive of the petiole which is 8-16 cm long and thick­ened at the base. The petiolule is up to 7 mm long. There are 2 stipels below the lateral leaflets. They are stipitate, cup-like, glandular and measure 2 mm long. The leaflets are ovate-triangular-­rhomboid, with terminal one being largest and measuring 8-16 cm x 6-14 cm. The base is rounded or cordate, acumi­nate at apex and hairless.

The inflorescence is racemose at the up­per leaf axils. It is 5-23 cm long and brownish-hairy. There are many flowers arranged in groups of 3. The peduncle is cylindrical, robust, measures 3-15 cm long and pubescent. The pedicel is 2-3 mm long, where in fruit it is up to 6 mm long. The sepal is bell-shaped, measures 1-1.5 cm long, splits open halfway down, hairy and yellow-green. The 5 petals are red where the upper part is broadly elliptical, shortly clawed, measuring 2.5-4 cm x 2-3 cm, scarlet and with numerous white stripes at the base inside. The wings are as long as the keel or slightly longer. They are about 1.5 cm long, and pale red with a blackish at the upper margin. There are 10 stamens which are 3-3.5 cm long, mon­adelphous but with vexillary stamen slightly shorter than the other ones. The pistil is with a hairy ovary.

The pod is flat, curved, measures 10-15 cm long and on a slender stalk 3-4.5 cm long. The lower part is seedless and it is 2-2.5 cm wide, while the upper part is thicker which is 1-1.5 cm wide and 1-5-seeded. It is septate between the seeds and dehiscent. The seed is ellipsoid, measuring 7-18 mm x 5-11 mm, smooth and dull black.

Ecology / Cultivation

Erythrina sub­umbrans occurs at low and. medium altitudes, from (0-)300-1500 m, in moist valleys, near streams, in open locations and sec­ondary forests. It requires a high annual rainfall with a maximum of 4 months with less than 100 mm rainfall, and a mean annual temperature above 22°C. It is reported, however, to occur gre­gariously on the Ijen plateau in East Java, in open grasslands, in stony or sandy, occasionally dry places; elsewhere, it is widely dispersed. The trees are fairly tolerant of wind, unless branches have been damaged by borers. The seeds are dispersed by water and occasionally by birds.

Line Drawing / Photograph

Erythrina_subumbrans

References

  1. Plant Resources of South-East Asia No.11: Auxiliary plants.