Cubilia (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Cubilia Blume

Protologue: Rumphia 3: 100 (1847).

Family: Sapindaceae

Chromosome number: x= unknown; 2n= unknown

Vernacular names

• Indonesia: amasi (Ambon), kamesi raindang (Minahassa), saninten sabrang (Sundanese)
• Philippines: kubili (general), baksian (Manobo), malasaging (Tagalog).

Origin and geographic distribution

Cubilia is a monotypic genus. Its single species is C. cubili (Blanco) Adelb. (synonyms: C. blancoi Blume, C. rumphii Blume) which occurs naturally in Borneo (East Kalimantan, Sabah), the Philippines, Sulawesi and the Moluccas, and is occasionally cultivated for its fruits in the Philippines, Sulawesi, the Moluccas and Java.

Uses

The timber of C. cubili is used for interior construction and general carpentry.

The young leaves are eaten as a vegetable. The arillode is edible, as are the seeds, which taste like chestnuts when cooked or roasted. The use of the fruits is probably more important than that of the timber.

Production and international trade

There are no records of the timber of C. cubili being traded commercially. In fact, the trees are seldom cut for timber because of the fruits, which are called "castanas" in the Philippines, where they are sold in local markets.

Properties

C. cubili yields a medium-weight hardwood with a density of 520-730 kg/m³at 15% moisture content. Heartwood whitish to reddish brown. Vessels moderately small.

The wood is moderately strong and moderately durable under cover. It is resistant to dry-wood termites. The sapwood is resistant to Lyctus.

The edible portion of the fruit contains 48.3% water, 5.2% protein, 1.9% fat, 23.1% starch, 18.8% other carbohydrates, 1.2% crude fibre and 1.5% ash. The energy value is 861 kJ/100g.

See also the table on microscopic wood anatomy.

Botany

• An evergreen, monoecious, small to medium-sized or rarely large tree up to 25(-50) m tall; bole straight, branchless for up to 12 m, up to 75 cm in diameter, with buttresses up to 6 m high; bark surface smooth, reddish-brown or greyish-brown; crown globose. Branches cinnamon or red-brown to purplish black.
• Leaves arranged spirally, paripinnate, 3-7-jugate, exstipulate; leaflets opposite to alternate, entire, often with naked glands in the vein axils below.
• Flowers in a terminal or pseudo-terminal panicle, unisexual, small, 5-merous; calyx with 5 small lobes; petals very small, included in the calyx, with 2 minute auricles at base inside; disk annular; stamens 5(-6); ovary superior, 2-locular with 1 ovule in each cell, stigma sessile, 2-lobed.
• Fruit composed of 2 parts, densely prickly.
• Seed dark brown, enveloped in the thin, entire arillode up to about halfway; testa shiny dark brown.
• Seedling with hypogeal germination; cotyledons not emergent, succulent; hypocotyl not elongated; first 2-4 leaves scale-like, first developed leaf often 1-jugate, subsequent ones with more leaflets.

Trees bearing flowers or fruits have been reported throughout the year. Flowers are pollinated by insects, probably bees. The seeds are probably dispersed by birds.

Ecology

C. cubili occurs in primary and secondary rain forest, often on poorly aerated, basic soils, often along rivers, up to 600(-1700) m altitude.

Silviculture

In the nursery the germination of C. cubili seed is fair and usually within a week.

Genetic resources and breeding

In the Philippines C. cubili trees are occasionally planted for their fruits, but there are no records of breeding.

Prospects

The wood properties of C. cubili are very poorly known and its use for timber is limited. Its use as a fruit tree is probably more important, but more research is needed on its cultivation.

Literature

70, 150, 238, 341, 436, 594, 632, 861, 907, 934, 1048.

U.A. Dasuki