Gonystylus spp.

Specifications

Family

Thymeleaceae

Species

Gonystylus spp.

Common name

Gonystylus spp.
Commonly known as

Description

It is undifferentiated, whitish or pale yellowish in color, sometimes with brown streaks or greenish central spots. It has a fine texture, mostly straight grain, and a density between 0.55 and 0.80. The presence of sharp fibers that can stick into the skin makes debarking dangerous. It has good mechanical strength but poor durability, except in cold climates.

Plant morphology

Trees up to 40 m tall with a columnar trunk with a maximum diameter of 50 cm. The leaves are stipuleless, alternate, simple, ovate, with entire margins and a mucronate tip. The flowers, about 8 mm in diameter, are greenish and borne at the tips of the branches. The fruit is a dehiscent capsule.

Natural occurrence

Countries of origin and distribution

Southeast Asia and Pacific Islands: Borneo, Sumatra, Solomon Islands, Fiji, Philippines.

Habitat and ecology

This species is widespread in primary forests dominated by Dipterocarpus sp., from the plains up to 300 m above sea level; it prefers well-drained soils on hillsides. Its presence in secondary formations indicates its permanence from the phase preceding human disturbance.

Uses

Use class

CU1

CU2

CU3

CU4

CU5

Application areas

It is used in light carpentry, furniture frames, interior design, skirting boards, toys, and household tools.

Threats and Conservation

Threats

The main factors threatening the conservation of these species are excessive harvesting for their timber, low regeneration capacity, and habitat loss and degradation. Slow growth and low regeneration rates, combined with overexploitation and the selective harvesting of mature individuals that could subsequently reproduce, are highly problematic. Habitat fragmentation and degradation, among other things, allow for the spread of fires, which exacerbate the situation.

Conservation measures

All species belonging to the genus Gonystylus are listed in CITES Appendix II, and therefore their trade is strictly regulated. Some species of the genus are present in ex situ collections and protected areas (BGCI 2017), but it is necessary to improve knowledge of population dynamics and promote sustainable forestry management.

IUCN Red List IUCN

Gonystylus affinis VU - Vulnerable - Vulnerable (2018); G. bancanus CR - Critically Endangered - Severely at risk of extinction (2018); G. brunnescens NT - Near Threatened - Close to threatened; G. calophyllus VU - Vulnerable - Vulnerable (2018); G. confusus LC - Least Concern - Low Risk (2021); G. macrophyllus LC - Least Concern - Low Risk (2018); G. maingayi VU - Vulnerable - Vulnerable (2018).

CITES. Year of assessment CITES

CITES Italia • Ultimo aggiornamento

Appendix II

Technical data

Aesthetic characteristics

Grain

Not obvious

Texture

Fine, Medium

Physical and mechanical properties

Density
ρ

660 kg/m³

Radial shrinkage
Rad. sh.

MPa

Tangential shrinkage
Tang. sh.

MPa

Bending strength
M.O.R.

112 MPa

Modulus of Elasticity
M.O.E.

19020 MPa

Durability characteristics

Fungal resistance

Not durable

Insect resistance

Not resistant

Miscellaneous

Commercially used species include: Gonystylus affinis Radlk., G. bancanus (Miq.) Kurz., G. brunnescens Airy-Shaw, G. caryophyllus Gilg., G. confusus Airy-Shaw, G. forbesii Gilg, G. macrophyllum Airy-Shaw, and G. maingayi Hook. Given the poor state of conservation in the wild of many of these species, the use of ramin should be avoided. In its fresh state, this wood has a pungent odor that is unpleasant to most Westerners, but is highly appreciated by locals, who use it in temples as a substitute for incense.