Articles

Derris microphylla (Miquel) B.D. Jackson

Derris microphylla (Miquel) B.D. Jackson

Family

Leguminosae

Synonyms

Brachypterum microphyllum Mi­quel, Derris dalbergioides Baker, Deguelia microphylla (Miquel) Valeton.

Vernacular Names

Malay­sia       

Daun berayai, batai, betek (Peninsular).

English          

Vetch tree

Indonesia     

Kayu retak (Palembang).

Thailand       

Khangten (south-eastern), di-ngu, fantae (peninsular).

Geographical Distributions

Derris mi­crophylla occurs naturally in Sumatra, Peninsular Malaysia, Thailand, Burma (Myanmar) and possi­bly in Indo-China. Its natural occurrence in Java, where it is often planted, is uncertain.

Description

Derris mi­crophylla is a tree with several ascending branches, with an umbrella-shaped, feathery crown and can reach up to 5-20 m tall. Its bark is light-grey to brown and slightly fissured. The branchlets, petioles and buds are golden-brown silky and nearly hairless.

The leaves are imparipinnate. The petiole and rachis are 9-20 cm long while the petiolule is 1-2 mm long. There are 19-43 leaflets, which are elliptical-oblong, measuring 1.5-3.2 cm x 0.8­1.2 cm, rounded-emarginate at both ends where both surfaces are thinly appressed brown hairy and glaucous below.

The inflorescence is an axillary raceme, and measures 2-13 cm long. The flowers are 7-8 mm long. The pedicel is 0.5-1.5 cm long. The sepal is bell-shaped while the petal is dark ­red to violet. The upper part of petal measures 9 mm x 7 mm that bears 2 glands at the base. There are 10 stamens which are monadelphous, where 1 sta­men is free at the top and the bottom but adnate to stamen tube in the centre.

The pod is flat, elliptical to lin­ear-Iance-shaped in outline, measuring 2.5-7 cm x 1.2-1.7 cm, 1-2(-5)­seeded, indehiscent, narrowed at both ends and smooth to hairy. The brown-green seed measures 6 mm x 3 mm.

Ecology / Cultivation

In Java and Peninsular Malaysia, Derris mi­crophylla occurs from 200-1200 m altitude. It is tolerant of strong winds. To provide shade in plan­tations, it is mostly planted in soils too poor for Leucaena leucocephala (Lamk) de Wit or Paraserianthes falcataria (L.) Nielsen.

Line Drawing / Photograph

Derris_microphylla

References

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