Albizia niopoides
(silk tree)

Identity

Preferred Scientific Name

• Albizia niopoides (Benth.) Burkart

Preferred Common Name

• silk tree

Other Scientific Names

• Acacia guacamayo (Britton & Killip) Standl.
• Albizia caribaea (Urb.) Britton & Rose
• Albizia caribaea (Urb.) Britton & Rose
• Albizia colombiana Britton
• Albizia guacamayo (Britton & Killip) L. Cárdenas
• Albizia hassleri
• Albizia hassleri (Chodat) Burkart
• Albizia richardiana King & Prain
• Feuilleea niopoides (Benth.) Kuntze
• Pithecellobium caribaeum Urb.
• Pithecellobium hassleri Chodat
• Pithecellobium niopoides Benth.
• Senegalia guacamayo Britton & Killip
• Senegalia liebmannii Britton & Rose

International Common Names

• English: guanacaste; monkey's earring
• Spanish: gallinazo; gavilana; guanacaste blanco

Local Common Names

• Bolivia: jebió
• Brazil: angico branco; gurujuba
• Colombia: guacamayo
• Grenada: wild tamarindo
• Paraguay: yvirá-yú; yvyrá-ju
• Peru: llambo paspaco; paspaco bianco
• Venezuela: camburi chiquito; carabeli; caro; hueso de pescado

Summary of Invasiveness

Albizia niopoides is a pioneer species often planted as an ornamental and shade tree. It is also used for forage and to improve soil conditions in disturbed areas. This species is a prolific seeder and seeds can germinate after being in storage for 1 to 2 years. Currently, A. niopoides is listed as invasive in Hawaii, India and Cuba, and can be found naturalized in Madagascar, Nigeria and Mauritius. It is an aggressive colonizer of abandoned pastures, roadsides, and other highly disturbed sites.

Taxonomic Tree

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Fabales
•                         Family: Fabaceae
•                             Subfamily: Mimosoideae
•                                 Genus: Albizia
•                                     Species: Albizia niopoides

Notes on Taxonomy and Nomenclature

The genus Albizia comprises about 150 species of small to large trees widely spread in the tropical and subtropical zones of Asia, Africa, Australia, and the Americas. The highest diversity of species is found in mainland Africa, Madagascar, and Central and South America (Nielsen 1981; Arce et al., 2008). This genus is placed within the subfamily Mimosoideae. The Mimosoideae comprises 82 genera and about 3,335 species of shrubs, trees and, rarely, herbs distributed mainly across tropical and warm temperate regions of the world (Stevens, 2019).

Description

The following description is from Vozzo (2002):

A medium to tall tree, 10 m to 30 m in height and 35 cm to 100 cm in dbh. The tree has straight bole and glabrous young twigs, greenish or yellowish with scarce lenticels. The bark is light gray or yellowish with exfoliating, thick scales in a concentric pattern; the scales leave crateriform scars that seem excavated with a chisel. Leaves are alternate, bipinnate, paripinnate; with 5 to 10 pairs of opposite pinnae, each with 30 to 55 pairs of pinnules. The leaf pinnules are (5-) 7-9 (-11) by 1 (-2) mm, linear, apex obtuse or acute, and glabrous. The petiole has a short pubescence and is pulvinate. The pulvinus is adaxial, basal, concave, and longitudinally oblong. The rachis is adaxially channeled, bearing an extrafloral nectary toward the distal end. The petiolules bear basal and adaxial pulvinuli. Stipules are 6 to 7 mm long, setiform, and deciduous. The fragrant, white flowers are grouped in pedunculate heads and are pentamerous, synsepalous and synpetalous. The calyx is tubular, distally toothed, and 1 mm long. The corolla is funnelform, valvate, and 2 to 3 mm long. The numerous stamens are basally united forming a tube. The anthers are small. The pod is laterally compressed (6 to 14 by 1 to 2.5 cm), straight, glabrous, thin, chartaceous, and longitudinally dehiscent. The seeds are ovate or oblong, laterally compressed, and without aril; the testa is thick, glossy, creamy or light brown, monochrome, hard, and osseous, with pleurogram, linea fissura open at the hilar end, and fracture lines.

Plant Type

Distribution

Albizia niopoides is native to tropical America from Mexico and Central America to Argentina, Trinidad and Tobago and the Lesser Antilles. This species is widely dispersed across the Amazon Basin in Brazil, Paraguay, Bolivia, Colombia, and Venezuela (ILDIS, 2009; Acevedo-Rodríguez and Strong, 2012; USDA-ARS, 2019). It has been introduced in India, Nigeria, Mauritius, Madagascar and Cuba (GRIIS, 2019; USDA-ARS, 2019).

Distribution Table

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Habitat

Albizia niopoides can be found growing in seasonally deciduous or semideciduous woodlands, riverine forest, moist forests and evergreen forests at elevations raging from near sea level up to 700 m in Central America, up to 1100 m in Brazil, and up to 1300 m in Peru (Iganci, 2015; New York Botanical Garden, 2019).

Habitat List

Biology and Ecology

Genetics

The chromosome number reported for Albizia niopoides is 2n=26 (Missouri Botanical Garden, 2019).

Reproductive biology

Albizia niopoides produces fragrant, white flowers that are grouped in pedunculate heads. This species is primarily pollinated by moths, but the flowers are also visited by other insects, hummingbirds, and passerine birds. Whether birds are visitors or pollinators is unknown (Guinet, 1981).

Physiology and phenology

Albizia niopoides is a semideciduous to deciduous species. In tropical regions trees lose their leaves during the dry season and produce new leaves with the arrival of the rainy season.

In Panama, Albizia niopoides has been recorded flowering and fruiting from February to June, while in Costa Rica flowers are produced from March to April and fruits are found from August to September. Seeds average about 22,500 per kg. Seeds have acceptable germination after storage for 1 to 2 years. Germination rates of 85% have been reported for this species (Vozzo, 2002).

Longevity and Activity patterns

Albizia niopoides is classified as pioneer to early or late secondary species and it is often found in pastures and open areas because it does not develop under canopy shade. It is an emergent tree in the canopy of primary dry forests in Central and South America and trees can reach a diameter >50 cm in approximately 52 years (Vozzo, 2002; Giraldo and del Valle, 2012; Silva et al., 2016).

A study in the Colombian Andes modelling growth rates of A. niopoides using dendro-chronological methods showed annual growth rates of 1.03 and 0.94 cm/year for individuals with ages of 18 and 46 years old respectively (Giraldo and del Valle, 2012).

Associations

In Brazil, different species of ants from the genera Nylanderia, Hypoponera, Wasmannia, Pheidole, and Pseudomyrmex have been recorded using the twigs of A. niopoides as nesting resource (Silva et al., 2016). As seen in other species in the Fabaceae family, Albizia niopoides shows association with nitrogen-fixing bacteria (Vozzo, 2002).

Environmental requirements

Albizia niopoides prefers to grow in tropical climates in areas with a mean annual temperature of 24°C to 32°C, and annual rainfall ranging from 1000 mm to 2500 mm. The species prefers alluvial soils and can survive in floodable soil provided it has good drainage (Vozzo, 2002).

Climate

Latitude/Altitude Ranges

Air Temperature

Rainfall

Rainfall Regime

Soil Tolerances

Soil drainage

• free
• seasonally waterlogged

Soil reaction

• acid
• alkaline
• neutral

Soil texture

• light
• medium

Notes on Natural Enemies

While inside the pod, the seeds of A. niopoides are often damaged by bruchids and weevils (Vozzo, 2002).

Means of Movement and Dispersal

Albizia niopoides spreads by seeds. Pods are dehiscent and when dry they burst open, releasing the seeds (Vozzo, 2002).

Pathway Causes

Pathway Vectors

Impact Summary

Environmental Impact

Albizia niopoides is a pioneer species that grows faster than many native species. Consequently, it displaces and outcompetes native plants, reducing native species diversity and negatively impacting natural successional processes. It is also a nitrogen-fixing species with the potential to change soil nutrient balance in invaded areas (Vozzo, 2002; Oviedo and Gonzalez-Oliva, 2015).

Risk and Impact Factors

• Proved invasive outside its native range
• Has a broad native range
• Abundant in its native range
• Highly adaptable to different environments
• Is a habitat generalist
• Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
• Pioneering in disturbed areas
• Benefits from human association (i.e. it is a human commensal)
• Long lived
• Fast growing
• Has propagules that can remain viable for more than one year

• Ecosystem change/ habitat alteration
• Modification of nutrient regime
• Modification of successional patterns
• Reduced native biodiversity
• Threat to/ loss of native species

• Competition - monopolizing resources
• Rapid growth

• Highly likely to be transported internationally deliberately

Uses

Social Benefit

Albizia niopoides is often planted as an ornamental and shade tree and to be used as forage. Its wood is used for light constructions, floors, furniture and boxes and as firewood. In South American natives used the saponin-rich roots to heal contusions and angina, and the boiled bark is used to heal scorpion bites. This species has been planted in grasslands and areas undergoing early natural regeneration because its nitrogen-fixing capacity improves the soil conditions. The tree is grown in coffee plantations in order to provide shade and organic matter for enriching the soil. The flowers provide good forage for bees (Vozzo, 2002; USDA-ARS, 2019; Useful Tropical Plants, 2019).

Uses List

Animal feed, fodder, forage

• Forage

Environmental

• Amenity
• Soil improvement

Fuels

• Fuelwood

Human food and beverage

• Honey/honey flora

Medicinal, pharmaceutical

• Traditional/folklore

Wood Products

Containers

• Boxes

Furniture

Sawn or hewn building timbers

• Flooring
• For light construction

References

Acevedo-Rodríguez, P., Strong, M. T., 2012. Catalogue of the Seed Plants of the West Indies, Washington, DC, USA: Smithsonian Institution.1192 pp. http://botany.si.edu/Antilles/WestIndies/catalog.htm

Arce, M. de L. R., Gale, S. L., Maxted, N., 2008. A taxonomic study of Albizia (Leguminosae: Mimosoideae: Ingeae) in Mexico and Central America. Anales del Jardín Botánico de Madrid, 65(2), 255-305. http://www.rjb.csic.es/publicaciones.php

David Giraldo, V., Ignacio del Valle, J., 2012. Growth modeling of Albizia niopoides (Mimosaceae) using dendrochronological methods. Revista de Biología Tropical, 60(3), 1117-1136. http://www.scielo.sa.cr/scielo.php?script=sci_arttext&pid=S0034-77442012000300013&lng=en&nrm=iso&tlng=es

GRIIS, 2019. Global Register of Introduced and Invasive Species. http://www.griis.org/

Guinet, P., 1981. Mimosoideae: the characters of their pollen grains. In: Advances in legume systematics. Part 2 [Polhill, R.M.; Raven, P.H. (Editors)] . Kew, Richmond, UK: Royal Botanic Gardens.835-857.

Iganci, JRV, 2015. Albizia niopoides. In: Lista de Espécies da Flora do Brasil, Rio de Janeiro, Brazil: Jardim Botânico do Rio de Janeiro. target="_blank">http://floradobrasil.jbrj.gov.br/jabot/floradobrasil/FB82616>

ILDIS, 2009. International Legume Database and Information Service. In: International Legume Database and Information Service Reading, UK: School of Plant Sciences, University of Reading.http://www.ildis.org/

Missouri Botanical Garden, 2019. Tropicos database. In: Tropicos database St. Louis, Missouri, USA: Missouri Botanical Garden.http://www.tropicos.org/

New York Botanical Garden, 2019. The C.V. Starr Virtual Herbarium. In: The C. Starr Virtual Herbarium New York, USA: New York Botanical Garden.http://sweetgum.nybg.org/science/vh/

Nielsen IC, 1981. Ingeae. In: Advances in Legume Systematics 1, [ed. by Polhill RM, Raven PH]. Richmond, UK: Royal Botanic Gardens, Kew. 173-179.

Oviedo Prieto, R., González-Oliva, L., 2015. National list of invasive and potentially invasive plants in the Republic of Cuba - 2015. (Lista nacional de plantas invasoras y potencialmente invasoras en la República de Cuba - 2015). Bissea: Boletín sobre Conservación de Plantas del Jardín Botánico Nacional de Cuba, 9(Special Issue No. 2), 1-88. http://repositorio.geotech.cu/jspui/bitstream/1234/1476/4/Lista%20nacional%20de%20plantas%20invasoras%20de%20Cuba-2015.pdf

PIER, 2019. Pacific Islands Ecosystems at Risk. In: Pacific Islands Ecosystems at Risk, Honolulu, Hawaii, USA: HEAR, University of Hawaii.http://www.hear.org/pier/index.html

Silva, O. G. M. da, Fernandes, T. T., Silva, R. R. da, Souza-Campana, D. R. de, Morini, M. S. de C., 2016. Twigs of Albizia niopoides (Spruce ex Benth.) burkart as a nesting resource for ants (Hymenoptera: Formicidae). Revista Brasileira de Entomologia, 60(2), 182-185. doi: 10.1016/j.rbe.2016.01.001

Stevens, P. F., 2019. Angiosperm Phylogeny Website. Version 14. In: Angiosperm Phylogeny Website. Version 14 . St. Louis, Missouri, USA: Missouri Botanical Garden.http://www.mobot.org/MOBOT/research/APweb/

USDA-ARS, 2019. Germplasm Resources Information Network (GRIN). Online Database. In: Germplasm Resources Information Network (GRIN). Online Database Beltsville, Maryland, USA: National Germplasm Resources Laboratory.https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysimple.aspx

Useful Tropical Plants, 2019. Useful tropical plants database. In: Useful tropical plants database : K Fern.http://tropical.theferns.info/

Vozzo, J. A., 2002. Agriculture Handbook (Washington), Washington, USA: United States Department of Agriculture, Forest Service (No.271), 899 pp.

Distribution References

Acevedo-Rodríguez P, Strong M T, 2012. Catalogue of the Seed Plants of the West Indies. Washington, DC, USA: Smithsonian Institution. 1192 pp. http://botany.si.edu/Antilles/WestIndies/catalog.htm

GRIIS, 2019. Global Register of Introduced and Invasive Species., http://www.griis.org/

Iganci JRV, 2015. Albizia niopoides. Rio de Janeiro, Brazil: Jardim Botânico do Rio de Janeiro. http://floradobrasil.jbrj.gov.br/jabot/floradobrasil/FB82616>

Oviedo Prieto R, González-Oliva L, 2015. National list of invasive and potentially invasive plants in the Republic of Cuba - 2015. (Lista nacional de plantas invasoras y potencialmente invasoras en la República de Cuba - 2015). Bissea: Boletín sobre Conservación de Plantas del Jardín Botánico Nacional de Cuba. 9 (Special Issue No. 2), 1-88. http://repositorio.geotech.cu/jspui/bitstream/1234/1476/4/Lista%20nacional%20de%20plantas%20invasoras%20de%20Cuba-2015.pdf

PIER, 2019. Pacific Islands Ecosystems at Risk. Honolulu, Hawaii, USA: HEAR, University of Hawaii. http://www.hear.org/pier/index.html

USDA-ARS, 2019. Germplasm Resources Information Network (GRIN). Online Database. In: Germplasm Resources Information Network (GRIN). Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysimple.aspx

Zuloaga FO, Morrone O, 1996. (Catalogo de las Plantas Vasculares de la Republica Argentina (Catalogo de las Plantas Vasculares de la Republica Argentina))., Missouri, USA: Missouri Botanical Garden. 323 pp.

Contributors

09/11/19 Original text by:

Julissa Rojas-Sandoval, Department of Botany-Smithsonian NMNH, Washington DC, USA

Distribution Maps