Flacourtia rukam Zoll. & Moritzi

Flacourtia rukam Zoll. & Moritzi

Family

Flacourtiaceae

Synonyms

Flacourtia euphlebia Merr.

Vernacular Names

Malaysia Rukam manis, rukam gajah.
English Rukam.
Indonesia Ganda rukem, rukam (Java), klang tatah kutang (Borneo).
Philippines Amaiit (Tagalog), aganas (Bisaya), kalominga (Igorot).
Laos Kén.
Thailand Takhop-thai (Central), khrop-dong (Pattani).
Vietnam Mung guân ru'ng.
French Prunier de Chine, prunier café.

Geographical Distributions

F. rukam is widely distributed but scattered, both cultivated and wild, all over Malaysia. It is apparently rare in the Moluccas and New Guinea. It has been introduced into Indo-China, India and Thailand.

Description

This is a small tree which can grow up to 5-15(-20) m tall. The trunk and old branches are usually crooked, furrowed and branched near the base. The young stem and branches are with strong, woody, simple or branched spines, up to 10 cm long and usually absent in clonally propagated trees.

The leaves are ovate-oblong or elliptic to oblong-lance-shaped, measuring (6.5-)10-15(-18) cm x (3-)4-7(-9) cm, hairless or hairy on the midrib and nerves, often shiny dark green above, brownish-red and drooping when young and with coarsely-toothed margins. The petiole is 5-8 mm long.

The inflorescences are in few-flowered, short, axillary and finely hairy racemes. The pedicels are 3-4 mm long. The flowers are greenish-yellow and usually unisexual. There are 4 sepals, but rarely 3-6, while petals are absent. The male flowers are with 8 orange or yellow-white fleshy disk-lobes and numerous stamens. The female flowers are usually without stamens, with 4-6(-8) styles, free and indistinctly bilobed stigmas.

The fruit is spherical, depressed-spherical to obovate berry, 2-2.5 cm in diametre, light-green to pink or purplish-green to dark red, with whitish, juicy, acid pulp and crowned by the 4-6(-8) small peg-like styles set in a circle.

There are 4-7 seeds and flat.

Ecology / Cultivation

F. rukam grows under humid tropical conditions up to 1500 m above sea level; it has been found growing wild at 2100 m elevation. Its natural habitat is primary or secondary forests, often along rivers, and the tree grows in the shade as well as in full sun. The tree appears to be fairly adaptable to a range of temperature, rainfall and soil conditions.

Line Drawing / Photograph

BOT00172

References

  1. Plant Resources of South-East Asia No.2: Edible fruits and nuts .