Araujia sericifera in the EPPO region: addition to the EPPO Alert List
Considering the potential of invasiveness and the limited presence of Araujia sericifera in the EPPO region, the Secretariat considered that this species could usefully be added to the EPPO Alert List.
Why: Araujia sericifera (Apocynaceae) is a woody evergreen vine native to South America. The plant was introduced during the 19th century as an ornamental and textile plant. Its common name is “Cruel plant”, as moths, bees and butterflies are often trapped and killed by the secretion within the flowers. Because A. sericifera has shown invasive behaviour where it has been introduced elsewhere in the world and is still limited in the EPPO region, it can be considered an emerging invader in Europe.
Geographical distribution
EPPO Region: France (Corse), Greece, Israel, Italy, Portugal (Azores, Madeira), Spain.
Africa: South Africa (Free State, Gauteng, Kwazulu Natal, Limpopo, Mpumalanga, North West, Western Cape).
North America: USA (California, Georgia).
South America (native): Argentina, Brazil, Paraguay, Uruguay.
Oceania: Australia (Australia Capital Territory, New South Wales, Queensland, Tasmania, South Australia, Victoria, Western Australia), New Zealand.
Morphology
A. sericifera is a climbing, evergreen vine reaching up to 10 m long and containing irritating and smelly sap. Stems are flexible, tough, and woody near the base. The opposed leaves are ovate-oblong, dark green and glabrous above, pale green and hairy below, 3-12 cm long and 2-6 cm wide. The bell shaped flowers are white, pale pink or creamish, and have corollas of 2-3 cm diameter. They occur in clusters of 2 to 4, and can trap and kill insects. Fruits are deeply grooved follicles, spongy, green if young, up to 12 cm long and 6 cm wide. They split to release about 400 black seeds of 7-8 mm length, each with a tuft of silky hairs of approximately 25 mm length.
Biology and ecology
The vine grows vigorously. The large quantities of seeds produced are viable for at least 5 years. Seeds are thought to be dispersed by the wind and by water.
Habitats
Banks of continental waters, riverbanks/canalsides (dry river beds), forests, arable land, permanents crops (e.g. vineyards, fruit tree and berry plantations, olive), green urban areas, including parks, gardens, sport and leisure facilities, road and rail networks and associated land, other artificial surfaces (wastelands).
Impacts
A. sericifera has dense foliage that smothers native shrubs and trees. Dense infestations prevent regeneration of native species. The heavy weight of fruiting vines can break tree branches. The sap of the plant is poisonous and causes skin irritation.
Control
Seedlings and smaller plants can be hand pulled or dug out, roots should be removed to prevent regrowth. Larger stems are cut at ground level, and the cut stumps treated with herbicide. Large infestations may be controlled by foliar sprays. Removed parts of the plant have to be gathered and destroyed, especially the fruits. Operators have to protect their skin and eyes from the abrasive milky sap of the plant by wearing long sleaves, gloves and protective glasses. A follow-up programme is necessary to control regrowth and seedlings for several years.
Sources
Agricultural Geo-Referenced Information System – South Africa – Weeds and Invasive Plants. http://www.agis.agric.za/wip
Australia’s Virtual Herbarium. http://www.rbg.vic.gov.au/cgi-bin/avhpublic/avh.cgi?session=113412310528776
Delivering Alien Invasive Species Inventories for Europe (DAISIE). http://www.europe-aliens.org/
Sanz Elorza M, Dana Sànchez ED, Sobrina Vesperinas E Eds (2004) Atlas de las plantas alóctonas invasoras en España. Dirección General para la Biodiversidad. Madrid, 80 pp.
Tutin TG, Heywood VH, Burges NA, Moore DM, Valentine DH, Walters SM and Webb DA (1964/80) Flora Europeaea, Vol 1-5. Cambridge University Press, Cambridge (GB).
USDA - Germplasm Resources Information Network (GRIN). http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?3841
Weber, E (2003) Invasive Plant Species of the World. CABI Publishing Wallingford, (GB) pp. 548, p. 51.