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Wedelia (Sphagneticola trilobata) - daisy invader of the Pacific Islands: the worst weed in the Pacific?

Thaman, Randolph R. (2009) Wedelia (Sphagneticola trilobata) - daisy invader of the Pacific Islands: the worst weed in the Pacific? [Conference Proceedings]

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Can a pretty daisy be compared with the likes of the Anopheles mosquito, the dreaded malaria vector; the brown tree snake that has brought birds and lizards in Guam to extinction; or fire ants that threaten endemic lizards and cause blindness in dogs in New Caledonia? I think so. “Wedelia”, creeping oxeye, or the trailing daisy, formerly known as Wedelia trilobata, but now as Sphagneticola trilobata, a deceptively beautiful, bright emerald-green creeper with bright yellow daisy-like flowers, is one of the world’s most aggressive weeds and listed among the worlds 1000 worst invasive alien species. Native to tropical America from Mexico to Brazil and throughout the Caribbean, wedelia is now cultivated, firmly established and has escaped from cultivation throughout the tropics and subtropics and in most of the main islands of Polynesia, Micronesia and Melanesia. Wedelia is out-of-control on the atolls of Kiribati, Tuvalu, Tokelau and the Tuamotus and the limestone island of Niue; and has rampantly spread into grazing areas, national parks, conservation areas, sensitive offshore islands, mangroves, swamps, towns, villages, and along rivers, coastlines and roads in Fiji, Palau, Pohnpei, Tahiti, New Caledonia and Papua New Guinea. Most attempts to control or eradicate it have failed, some at considerable cost. It is suggested that wedelia should be immediately declared a serious noxious weed, should be restricted from introduction into new islands and habitats, and, where possible, eradicated from islands, habitats where it is yet to gain a firm foothold. If action is taken NOW, islands and communities throughout the Pacific can prevent the spread of Wedelia BEFORE it replaces extensive areas of indigenous, where it out-competes plants of considerable ecological and cultural importance. This conclusion is based on my studies of Wedelia over the past 30 years in most of the countries and territories of the Pacific.

Item Type: Conference Proceedings
Subjects: S Agriculture > SB Plant culture
Divisions: Faculty of Science, Technology and Environment (FSTE) > School of Geography, Earth Science and Environment
Depositing User: Users 24 not found.
Date Deposited: 24 Jan 2009 21:16
Last Modified: 19 Jun 2012 08:51

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