Guiacum spp.

Specifications

Family

Zygophyllaceae

Species

Guiacum spp.

Common name

Guiacum spp.
Commonly known as

Description

The sapwood is whitish and the heartwood is dark green, grayish brown, or bronze. It has a greasy appearance, a fine texture, often interwoven grain, and a density of 1.10 to 1.30. Drying and all processing are difficult due to its extreme hardness. Its mechanical strength is very high, and its durability is excellent even in humid environments.

Plant morphology

Slow-growing trees or shrubs, they can reach heights of 20 m but are typically less than half that height. The bark is greenish-brown and fissured. The leaves are pinnate, oval or oblong, and obtuse. It produces blue flowers and cord-shaped capsules.

Natural occurrence

Countries of origin and distribution

Central America: Anguilla, Antigua and Barbuda, Bahamas, Barbados, Belize, Colombia, Costa Rica, Cuba, Dominica, Dominican Republic, Florida, Grenada, Guadeloupe, Guatemala, Haiti, Honduras, Jamaica, Martinique, Mexico, Montserrat, Nicaragua, Netherlands Antilles, Panama, Puerto Rico, Saint Barthélemy, Saint Martin, Saint Vincent and the Grenadines, Turks and Caicos Islands, Venezuela, Virgin Islands. Introduced in Thailand.

Habitat and ecology

Species of dry plain forests, they frequently grow in coastal areas.

Uses

Application areas

It is used for handles, sports tools, turned objects but is particularly appreciated for bearings and propeller shaft supports.

Threats and Conservation

Threats

These species are near extinction due to their historical overexploitation for timber and, at one time, for medicinal purposes. Both legal and illegal trade in their wood continues to pose a serious threat.

Conservation measures

Guaiacum officinale and G. sanctum are included in Appendix II of CITES, the first species is present in protected areas and also cultivated in various ex situ collections (BGCI 2018).

IUCN Red List IUCN

Guaiacum officinale EN - Endangered (2017); Guaiacum sanctum EN - Endangered (1998).

CITES. Year of assessment CITES

CITES Italia • Ultimo aggiornamento

Guaiacum officinale Appendix II, 11/06/1992; G. sanctum Appendix II, 01/07/1975.

Technical data

Aesthetic characteristics

Grain

Obvious

Texture

Fine

Physical and mechanical properties

Density
ρ

1260 kg/m³

Radial shrinkage
Rad. sh.

MPa

Tangential shrinkage
Tang. sh.

MPa

Bending strength
M.O.R.

124 MPa

Modulus of Elasticity
M.O.E.

17110 MPa

Durability characteristics

Fungal resistance

Very durable

Insect resistance

Resistant

Miscellaneous

From a commercial standpoint, the species of interest are: Guaiacum officinale L. and G. sanctum L. Given their poor state of preservation in the wild, their use should be avoided. The wood is more or less aromatic, and a volatile oil is extracted from it, used in perfumery to adulterate rose essence. The balsamic resin secreted by the trunks is used medicinally as an antirheumatic, diaphoretic, and purifying agent.