Taxonomic name: Acacia farnesiana (L.) Willd.
Synonyms: Acacia acicularis Humb. & Bonpl. ex Willd., Acacia densiflora (Alex. ex Small) Cory, Acacia edulis Humb. & Bonpl. ex Willd., Acacia farnesiana (L.) Willd. var. pedunculata (Willd.) Kuntze, Acacia ferox M. Martens & Galeotti, Acacia indica (Pers.) Desv., Acacia lenticellata F.Muell., Acacia minuta (M.Jones) Beauchamp subsp. densiflora (Alex. ex Small) Beauchamp, Acacia pedunculata Willd., Acacia smallii Isely, Farnesia odora Gasp., Mimosa acicularis Poir., Mimosa farnesiana L., Mimosa acicularis (Humb. & Bonpl. ex Willd.) Poir., Mimosa edulis (Humb. & Bonpl. ex Willd.) Poir., Mimosa farnesiana L., Mimosa indica Pers., Mimosa pedunculata (Willd.) Poir., Vachellia densiflora Alex. ex Small, Vachellia farnesiana (L.) Wight & Arn., Vachellia farnesiana (L.) Wight & Arn. var. typica Speg., Vachellia farnesiana (L.) Wight & Arn. forma typica Speg.
Common names: acacia jaune (French), aroma (Guam), aromo (Spanish-spain), ban baburi (Fiji), carambuco (Spanish-Spain), cashia (Puerto Rico), cassie (French), debena (Nauru), Ellington curse, espino blanco (El Salvador), espino ruco (El Salvador), esponja (Portuguese-Brazil), esponjeira (Portuguese-Portugal), huisache (Mexico), huisache dulce (Spanish), kandaroma (Commonwealth of the Northern Mariana Islands), klu (English), klu bush, kolu (Hawaii), mimosa (Spanish-Spain), mimosa bush (Australia), needle bush (Australia), oki (Fiji), opoponax (southern United States), popinac (Guam), popinac (Commonwealth of the Northern Mariana Islands), rayo (Puerto Rico), Small's acacia (English), sweet acacia (English), tekaibakoa (Kiribati), titima (Cook Islands), vaivai vakavotona (Fiji), Westindische akazie (German)
Organism type: tree, shrub
Probably a native of tropical America, Acacia farnesiana was introduced to many tropical countries for its bark, gum, seed and wood. It is often planted as an ornamental or to check erosion, and is also used in the perfume industry because of its scented flowers. This thorny, deciduous shrub grows to 4m in height forming impenetrable thickets or sometimes a more open cover and prefers dry habitats between sea level and 1000 m. In Australia it occurs along watercourses on rangeland and farmland limiting access to water. It has also become an invasive species in Fiji, French Polynesia, New Caledonia, Solomon Islands, and Vanuatu.
"This thorny, deciduous shrub grows to 4 metres in height, sometimes forming impenetrable thickets, although in most areas it forms a more open cover" (Smith, 1985. In PIER, 2002). "Erect much-branched shrub; leaves with 4-8 pairs of pinnae, pinnae with 10-12 pairs of small asymmetric leaflets ; stipular thorns straight and slender; flowers in pedunculate axillary heads, 1-3 heads together, subglobose; flowers yellow, fragrant; heads about 1-1,5cm across; stamens numerous; pods dark brown or black, up to 8cm long, to 12mm broad, plump, often slightly curved; pulp within sweetish; seeds compressed, elliptic, brown" (Stone, 1970, in PIER, 2003) (differences according to Paiva, 1999).
Acacia nilotica, Prosopis spp.
agricultural areas, coastland, desert, range/grasslands, riparian zones, ruderal/disturbed
Acacia farnesiana thrives in dry localities and on loamy or sandy soils where it may serve as a sand binder (ranging from warm temperate dry through tropical desert to moist forest life zones, Acacia farnesiana is reported to tolerate annual precipitation of 6.4 – 40.3 dm (a mean of 20 cases is 14.0 dm), annual mean temperature of 14.7–27.8°C (mean of 20 cases = 24.1°C), and pH of 5.0–8.0 (mean of 15 cases = 6.8) (Duke, 1983). Dry habitats between sea level and 1000m (PIER, 2002). Smith (1985 In PIER, 2002) reports that
although the aerial portions may be killed by fire, this plant soon regenerates from basal shoots.
Acacia farnesiana can spread readily and grow quickly, (Land Protection, 2001). As it often forms thorny thickets along some watercourses in Australia, it can be a considerable nuisance during mustering and can also hinder access to water (Land Protection, 2001). While access is less of a problem in areas where cattle graze on the mimosa, they readily eat the nutritious seed pods assisting its spread.
A tree of economic importance in South and East Africa, Rhodesia, India and the Rio Grande do Sul area of South America (Duke, 1983). The bark and the pods are a source of tannin and are used for tanning and dying leather (University of Connecticut, 2003). The flowers provide a fragrant essential oil which is used in the perfume industry as a violet scent substitute (Le Hou'erou, 2002). A gummy substance obtained from the pods is used in Java as cement for broken crockery. Other parts of the plant are used as an ingredient in the Ivory Coast for arrow poison (University of Connecticut, 2003). Trees add nitrogen and organic material, which improve the soil and are sometimes used for erosion control on poor sloping soils unsuitable for agriculture (Duke, 1983). Products are often used in folk medicine as styptics or astringents (Duke, 1983). In India and some African countries the pods are used as substitute for tamarind Tamarindus indica L. (Paiva, 1999). Cultivated in S.W. Europe for ornamental purposes and for perfumery industry (Tutin et al, 1992).
In Hawaii Acacia farnesiana was formerly cultivated for an attempted perfume industry. It is now naturalised and common, sometimes becoming a pest in dry, open, disturbed areas, 2-400m (Wagner et al., 1999. In PIER, 2002). Although the aerial portions of the plant may be killed by fire, it soon regenerates from basal shoots, (Smith, 1985. In PIER, 2002). In Spain Acacia farnesiana is naturalised in rocky, poor soils (Paiva, 1999)
Native range: Probably native to tropical America (Dominican Republic - Tutin et al, 1992).
Known introduced range: Naturalised and cultivated all over the world. It is recorded in Africa (e.g. Rhodesia, Mozambique and coastal areas of Ghana), the Arabian penninsula,Indian Ocean islands, Pacific ocean islands, Pacific rim including Australia, Pakistan. Grown throughout India and often planted in gardens. An invasive species in Fiji, French Polynesia, New Caledonia, Solomon Islands, and Vanuatu (Waterhouse, 1997). Reported by Waterhouse (1997) to be present in Niue but not seen there in a more recent survey (PIER, 2002). Naturalized in Spain (Paiva, 1999), France, Italy and Sicilia (Tutin et al., 1992). Cultivated in Gardens in Portugal and in Madeira Island (Franco, 1943)
Introduction pathways to new locations
Agriculture: In Hawaii, formerly cultivated for an attempted perfume industry (Wagner et al., 1999. In PIER, 2002)
Local dispersal methods
Consumption/excretion: The seed pods are nutritious and readily eaten by ungulates, which assist in the spread of this species. (PIER, 2002)
Preventative measures: A Risk Assessment of Acacia farnesiana for Hawai‘i and other Pacific islands was prepared by Dr. Curtis Daehler (UH Botany) with funding from the Kaulunani Urban Forestry Program and US Forest Service. The alien plant screening system is derived from Pheloung et al. (1999) with minor modifications for use in Pacific islands (Daehler et al. 2004). The result is a score of 14 and a recommendation of: "Likely to cause significant ecological or economic harm in Hawai‘i and on other Pacific Islands as
determined by a high WRA score, which is based on published sources describing species biology and behaviour in Hawai‘i and/or other parts of the world."
Physical: "Destroyed by cultivation and grubbing" (Swarbrick, 1997. In PIER, 2002). Although the aerial portions may be killed by fire, it soon
regenerates from basal shoots"" (Smith, 1985). Once established, the seedlings grow rapidly and resprout readily following damage or top removal. Acacia
farnesiana sprouts may grow to almost half their original total plant height within 5 months after shredding (Powell et al., 1972). Thus, mechanical top
removal results in only short-term suppression of A. farnesiana (Mutz et al. 1978) and gives the species competitive advantage over associated, slower
growing woody plants. Almost pure, dense stands of A. farnesiana may develop within two to three growing seasons following brush control methods that
disturb the soil.
Chemical: Probably susceptible to translocated herbicides, including picloram, metsulfuorn-methyl, glyphosate and triclopyr, and possibly 2,4-D applied to the foliage, freshly cut stumps or by stem injection at standard rates.
Also probably susceptible to residual herbicides, including tebuthiuron and hexazinone (Swarbrick, 1997 in PIER, 2002). "Sensitive to foliar applications of triclopyr at 1 lb/acre and metsulfuron at 0.45 oz/a and to basal bark applications of 2,4-D or triclopyr at 2% in diesel. Drizzle applications were not effective in foliar and basal bark trials at Kihei, Maui, but these trials were confounded by a severe drought" (Motooka et al. 2002. In PIER, 2002).
Acacia farnesiana can fix atmospheric nitrogen through symbiotic relation with Rhizobium allowing growth in nitrogen poor soils. Thrives on poor, dry soils but favours deeper, moister, more fertile soils (Duke, 1983).
It is a prolific seed producer (Scifres, 1974). The seeds readily germinate after soil disturbance and plants grow rapidly (Mutz et al., 1978, Land Protection, 2001). Seeds are dispersed by ungulates which eat the pods (PIER, 2002).
Reviewed by: Dr. Hélia Marchante. Escola Superior Agrária de Coimbra Departamento de Ciências Exactas e Ambiente Sector de Biologia e Ecologia, Bencanta. 3040-316 Coimbra Portugal.
Compiled by: IUCN/SSC Invasive Species Specialist Group (ISSG)
Last Modified: Thursday, 23 March 2006