The Target 10 Homepage co-ordinates actions and organisations in understanding and controlling problem species.

Ireland's National Plant
Conservation Strategy

is a response to the
Global Strategy for
Plant Conservation

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National Botanic Gardens Home Page

vert bar Heracleum mantegazzianum
Last updated 12th April 2007

First noted as an escape from cultivation in Co. Dublin 1902-03, Colgan predicted that this species could become quite naturalized (FDub 1904); Praeger (1939) added records for Newport River in Limerick and N Tipperary, and by two streams in Fermanagh and Tyrone; by mid-20th C, H. mantegazzianum had been recorded from some 13 vice-counties. The main expansion in range occurred in the second half of the 20th C, and there are records for over 30 vice-counties since the early 1970s; see Wyse Jackson (1989) for early history and records up to late 1980s, and since then, e.g. Scannell 1991 (Reynolds 2002).


A four-year treatment program, using glyphosate, was undertaken in the Mulkear River catchment of the lower River Shannon. Weed treatment commenced in March 1998 and continued to 2001. Results were very encouraging. The benefits to the local community and the overall ecology of the river and riparian habitats are discussed in the publication (Caffrey 2001).


If you have information about any other populations of Heracleum mantegazzianum please notify the following:-
Matthew Jebb
National Botanic Gardens
Dublin 9
matthew.jebb at


Joseph M. Caffrey (2001) The Management of Giant Hogweed in an Irish River Catchment. J. Aquat. Plant Management 39: 28-33

Wyse Jackson, M. (1989) Observations on the Irish distribution of a plant with serious public health implications: Giant hogweed (Heracleum mantegazzianum Sommier and Levier). Bull. Ir. biogeog. Soc. 12: 94-112.