- General characteristics
- Appearance
- Foliage
- flowers
- Fruit
- Taxonomy
- Etymology
- Synonymy
- Habitat and distribution
- Plagues and diseases
- Applications
- Industrial
- Medicinal
- Ornamental
- References
The guayacán (Guaiacum officinale) is a perennial tree species of short or medium growth belonging to the Zygophyllaceae family. Known as guayacán de las Antillas, palo santo de América or palo de las Indias is a native species of the American tropics.
Of sinuous growth, it can reach 15 m in height. The stem has a smooth and variegated bark crowned by a wide, oval crown. Its dense foliage is made up of bright green foliated leaves and numerous purplish-blue flowers with yellow stamens.
Guayacán (Guaiacum officinale). Source: Photo by David J. Stang
It grows on flat, slightly undulating and stony terrain, in warm and dry forest ecosystems up to 500 meters above sea level. It is widely distributed in the Caribbean islands, Cuba, Jamaica, Puerto Rico and the Dominican Republic, as well as in Panama, Colombia and Venezuela.
Its heavy, compact and resinous wood was until recently a highly commercialized product. However, at present its production is so scarce that it is hardly used for carving handicrafts and obtaining charcoal.
On the other hand, the bark has various active principles that favor its use as an anti-inflammatory, diuretic and laxative, it is even used to relieve arthritis and syphilis. In addition, on many islands in the Caribbean and the Atlantic coast it is cultivated as an ornamental species due to its evergreen foliage and attractive flowering.
Indeed, it is a species of high ornamental value due to its bearing and blue, purple and white flowers. As well as yellowish fruits and seeds covered by a reddish mantle that contrasts with the bright green color of its foliage.
General characteristics
Appearance
It is a low to medium perennial shrub species with slow growth that reaches 8-15 m in height. The generally sinuous stem has gnarled branches with smooth bark and shallow grooves, its wood is extremely hard.
The very hard and heavy wood called "lignum vitae" is obtained from the trunk of the Guaiacum officinale, which contains a resin with medicinal properties. The crown has dense and leafy foliage in a rounded shape, which is why it is frequently used to provide shade in sunny places.
Foliage
The opposite, pinnate and veined leaves are composed of 2-3 pairs of leathery green leaflets with a glossy surface. Each 6-14 cm long leaflet lacks a petiole and is attached to a thin central branch.
They usually have a great variety in size and shape, while some are wider or obovate, others are blunt or blunt. Its dense and compact foliage shows a closed, bright green appearance.
flowers
The solitary purple or deep blue flowers grow in great abundance and are grouped in axillary or terminal peduncles. The flowers remain on the tree for a long time and as they age they become lighter, almost white.
Each flower has five broad, concave petals two-thirds larger than its sepals. As well as a small pubescent calyx with ten stamens of large golden anthers, attached to a thin peduncle.
Flowering occurs at any time, both in spring and autumn, and they last for approximately 25-30 days. In areas of the Caribbean, such as the island of Cuba, flowering occurs during the months of March to May.
Guayacan flowers (Guaiacum officinale). Source: pixabay.com
Fruit
The fruit is a small flattened, rounded and dry yellow-green capsule that contains two to five cells. In each cell a solitary seed is located.
When ripe, the fruits turn orange or brownish-orange, being so abundant that they contribute to the ornamental effect of the species. On the plant, the ripe fruits open and expose their fleshy seeds covered by a reddish aril.
Taxonomy
- Kingdom: Plantae
- Division: Magnoliophyta
- Class: Magnoliopsida
- Order: Zygophyllales
- Family: Zygophyllaceae
- Subfamily: Larreoideae
- Genus: Guaiacum
- Species: Guaiacum officinale L. 1753
Etymology
- Guaiacum: the generic name derives from the macro-Arawacan language or macro-Arawak dialect of the Taínos of the Bahamas. This name was adopted by the English in 1533, being the first word of this language of American origin.
- officinale: specific adjective from Latin that means "medicinal or for sale in herbs."
Leaves and fruits of guayacán (Guaiacum officinale). Source: José E. Martínez González
Synonymy
- Guaiacum bijugum Stokes.
- Guaiacum breynii Spreng.
Habitat and distribution
The guayacán grows in ecosystems of tropical dry forest and xerophytic scrub on sandy and stony soils of coastal areas of Central and South America. This species is found in the wild in Colombia, Costa Rica, the United States, Guatemala, Honduras, Mexico, Nicaragua, Panama and Venezuela.
It is also distributed throughout the Caribbean in Antigua and Barbuda, Bahamas, Barbados, Cuba, Dominica, Grenada, Guadeloupe, Haiti and Jamaica. In addition, in the Virgin Islands, Montserrat, Martinique, the Netherlands Antilles, Puerto Rico, the Dominican Republic, Trinidad and Tobago, Saint Kitts and Nevis, Saint Lucia and Saint Vincent.
Its natural range includes the South Caicos in the Bahamas, the Greater Antilles, and the Lesser Antilles, including Aruba, Bonaire, and Curaçao. In some regions tourism development, commercial planting of other species and fires have extinguished many specimens.
As an ornamental species, it is widely cultivated in southern Florida, in Bermuda and other tropical areas of the region. In India and Ghana it has been introduced and feral as an exotic species.
Guayacan bark (Guaiacum officinale). Source: Photo by David J. Stang
Plagues and diseases
The Guayacán is frequently attacked by Coleoptera, Homoptera, Lepidoptera, Orthoptera and Thysanoptera without causing damage of commercial value. In fact, these species of insects can cause the total defoliation of the plant without causing its death.
On the other hand, dry wood is highly resistant to Crytptotermes brevis termites. In addition, thanks to the presence of resins, it is an excellent repellent against the sea moth or Teredo spp.
Regarding diseases, no incidences of economic importance have been reported. However, at the nursery level and during the establishment of the crop, rot or damping-off caused by fungi of the genus Sclerotium may occur.
However, the main natural enemy of Guayacán is represented by human beings. In its wild environment it has almost completely disappeared due to burning and indiscriminate logging.
However, in some areas such as Barbuda Island, the production of Guayacán has remained commercially together with livestock exploitation. It is common to observe large plantations with a marked grazing line at a certain height without causing severe damage to the trees.
Applications
Industrial
From Guayacán, sapwood and heartwood are used for their high industrial value. The wood of fine texture, dark color, hard and very heavy, is slightly oily to the touch due to the presence of the resin «guaiaca».
Its density varies between 1.20-1.35 gr / cc dried in the environment or 1-1.10 gr / cc dried in the oven. It is a difficult wood to dry unless the ends of the logs are indented, ridged or glued.
This wood is considered harder than Quercus robur L. (oak) or any other forest species commercialized in the United States. It is a difficult material to work with with manual or electrical equipment, but it turns, shapes and sands perfectly.
From Guaiacum officinale the true "lignum vitae" is obtained, a wood with a high content of resins with particular properties. This natural resin is a colorless compound that turns blue on contact with ingredients that contain peroxidases, being used in pharmacology.
Guayacán in bloom. Source: Jayesh Patil
The presence of resins, which sometimes constitutes a quarter of their weight, favors obtaining a smooth and waterproof finish. Indeed, its hardness and self-lubricating property have allowed its use as supports, sockets, mallets or pulleys in steamships.
Despite the fact that Guayacán has disappeared from some regions, in some rural areas its wood is used to make rustic furniture. This hard and heavy wood is used to make kitchen cutting boards, mallets and mortars, to handcrafted carvings.
In islands such as Haiti, its disappearance is attributed to its use for the manufacture of blue or green dyes. On the other hand, at the local level, firewood is used to obtain charcoal of low commercial value.
Medicinal
Guayacán has been used in herbology for the treatment of different diseases. Since ancient times, pre-Columbian cultures have used the extract of the wood for the treatment of syphilis.
The resin obtained from the bark applied topically allows to relieve toothache and cure skin diseases, rheumatic pain and inflammation. Cooking the bark stimulates the digestive system and reduces the problems caused by laryngitis and pharyngitis.
In some areas of the Caribbean, such as the Lesser Antilles, a tea called "bush tea" is made with abortifacient properties. However, its use is restricted because an overdose can be fatal to those who consume it.
Ornamental
This species is used as an ornamental in various tropical areas with dry and humid environments, especially in the Caribbean region. In fact, the Guayacán is an evergreen tree with dense, broad, bright green foliage with attractive seasonal flowers.
As an ornamental plant it can be regularly pruned into a hedge, its only disadvantage being its slow growth. The abundant and frequent flowering is a source of nectar for the various honey species.
References
- Francis, JK (1993). Guaiacum officinale L. Lignum vitae. Guayacan. Zygophyllacea. Caltrop family. USDA Forest Service, International Institute of Tropical Forestry; 4 p. (SO-ITF-SM; 67).
- Guaiacum officinale. (2019). Wikipedia, The Free Encyclopedia. Recovered at: es.wikipedia.org
- Guaiacum officinale (2014) Virtual catalog of flora of the Aburrá Valley by UEIA. Recovered at: catalogofloravalleaburra.eia.edu.co
- Guaiacum officinale (2012) Plants For A Future. Recovered at: pfaf.org
- López Toledo, L., Ibarra Manríquez, G. & Martínez Ramos, M. (2013) Guayacán. CONABIO. Biodiversitas, 107: 12-16.
- Orwa, C., Mutua, A., Kindt, R., Jamnadass, R., & Anthony, S. (2009). Agrofores tree Database: a tree reference and selection guide version 4.0. World Agroforestry Center, Kenya, 15.
- Zygophyllaceae: Guayacán - Guaiacum officinale L. (2012) Trees in the Dominican Republic. Recovered at: cedaf.org.do