Palaquium leiocarpum (PROSEA)

Plant Resources of South-East Asia Introduction

List of species

Palaquium leiocarpum Boerl.

Protologue: Bull. Inst. Bot. Buitenzorg 5: 24 (1900).

Synonyms

• Palaquium molle Pierre (1902),
• Croixia leiocarpa (Boerl.) Baehni (1965).

Vernacular names

• Indonesia: jongkang, getah hangkang, hangkang (Kalimantan)
• Malaysia: nyatoh jangkar, jangkai (Sarawak).

Distribution

Borneo and Sulawesi; possibly also Peninsular Malaysia.

Uses

The timber is used as nyatoh. The latex gives gutta-percha of rather inferior quality; it is often mixed with superior types of gutta-percha.

Observations

• A small to fairly large tree up to 35 m tall.
• Leaves evenly distributed or loosely clustered at tip of twigs, ovate, obovate or elliptical, with few transverse tertiary veins almost parallel to secondary veins and with a reticulate venation in between, velvety beneath.
• Flowers in 3-6-flowered clusters, borne on 8-15 mm long pedicels (in fruit up to 30 mm), whitish.
• Fruit globose to ellipsoid, 1.5-2.5 cm long, glabrous.

In Peninsular Malaysia a Palaquium species is found which is close to P. leiocarpum or perhaps represents this species. It is a large tree up to 40 m tall with bole up to 75 cm in diameter and large plank buttresses and frequently also stilt roots; locally it is very common in freshwater swamps and on hillsides up to 200 m altitude.

In Borneo, P. leiocarpum is found in primary forests at low altitudes, but sometimes up to 1000 m. The timber is fairly heavy for nyatoh with a density of 610-790 kg/m³ at 15% moisture content. The gutta-percha obtained from this species contains much resin (about 70%) and little poly-isoprene (about 30%).

Selected sources

36, 100, 102, 318, 461, 730, 743, 779.

Main genus page

• Palaquium (Timbers)

Authors

• R.H.M.J. Lemmens (selection of species)