Plans for the eradication of small populations of Asphodelus fistulosus from the West Coast of South Africa
Nolwethu Jubase1, Ernita van Wyk1 and Stephen Boatwright2
1Invasive Species Programme, South African National Biodiversity Institute, Private Bag X7, Claremont, 7735.
2Department of Biodiversity and Conservation Biology, University of the Western Cape, Private Bag X17, Bellville, 7535, South Africa.
Asphodelus fistulosus (onion weed), native to Europe, was recently recorded in South Africa for the first time and represents a first record of an invasive member of the Asphodelaceae family in South Africa. So far, five small populations (<100 m2) of this plant have been found along disturbed roadsides in deep sandy soils on the West Coast of South Africa. The known extent of the infestation in South Africa is still limited, such that it may be a feasible eradication target. The species is an aggressive invader in other parts of the world, notably South West Australia and Califonia. Very little information is available to guide the practical management of this species. To confirm the current extent and the feasibility of eradication, we propose to: a) survey known A. fistulosus patches in a predetermined radius from each population and along all the nearby roadsides; b) distribute pamphlets asking for sightings of the plant; c) compare the efficacy of two control methods (chemical vs. mechanical); and d) monitor the post-treatment recovery of A. fistulosus. We hope to determine whether eradication is feasible for this species, and what control method is most effective.