Problematic Plant Species : Top 39 - National Invasive Species ...

National Invasive Species Database
Problematic Plant Species : Top 39
Invasive alien plant species are species that have been introduced, generally by
human intervention, outside their natural range and whose establishment and spread
can threaten native ecosystem structure, function and delivery of services. Once
introduced, control, management, and eradication where possible, of invasive species
can be very diffi cult and costly; therefore early detection and reactive measures
are desirable. Currently invasive species records are not centrally maintained. In
response to this, the National Biodiversity Data Centre has established a National
Invasive Species Database that will provide centralised up-to-date information on
the distribution of invasive species in Ireland. This database will play a key role in
recording, monitoring and surveillance programs.
Once a valid biological record is received it will be publically displayed on the National
Biodiversity Data Centre’s web GIS mapping system. For every additional record that
is submitted, a clearer picture of the status of that invasive species in Ireland is
generated. Display of such data against the backdrop of additional GIS layers will
greatly enhance the information available to those involved in combating the threat
of invasive species in Ireland. The 39 species listed in this booklet are the initial focus
of record collection in the establishment phase of the database.
Why these Top 39?
This list includes species which are not extremely widespread but which are
considered a problem or a potential problem in Ireland. This list was initially
compiled by Sylvia Reynolds in June 2007 and was agreed by Dr. Matthew Jebb
of the National Botanic Gardens. An additional seven more widespread
species (*) have been added to ensure overlap with the plant species
recognised by the Invasive Species Ireland project as Ireland’s
most unwanted invasives. The inclusion of Cotoneaster
integrifolius is based on the recommendation of the
Clare Biodiversity Group.
Problematic Terrestrial Species
Scientifi c name Common name Habitat recorded in
Acaena anserinifolia Bronze Pirri-pirri-bur Gardens and rockery.
Acaena novae-zelandiae Pirri-pirri-bur
Acaena ovalifolia Two-spined Acaena
Carpobrotus edulis Hottentot-fi g Coastal cliffs, rocks, sand.
Cotoneaster integrifolius
Entire-leaved
Cotoneaster
Wet slopes, castle gardens, rough pastures, grassy areas and
woods.
Demesne woodlands, roadsides, by streams, sandstone quarry
and lowland pasture.
Rocky substrates, walls, lakeshores, roadsides, railway banks,
sand dunes, woodland and urban habitats.
Cyperus eragrostis Pale Galingale Waste ground, rock outcrops, gravel shores, and roadsides.
Fallopia japonica* Japanese Knotweed
Demesnes, parks, river banks, roadsides, waste ground,
rubbish tips and coastal islands.
Gaultheria mucronata Prickly Heath Acid soils, moorland, woodland, quarries and coastal habitats
Gaultheria shallon Shallon Parks and demesnes.
Gunnera tinctoria* Giant-rhubarb
Heracleum
mantegazzianum*
Giant Hogweed
Impatiens glandulifera* Indian Balsam
Juncus planifolius Broad-leaved Rush
Lagarus ovatus Hare’s-tail Sandy beaches
Boggy ground, damp pastures, ditches, roadsides and by
streams.
Damp ground along rivers and streams, roadsides, waste
ground, walls, rubbish tips
Damp ground, along rivers, streams and lake margins,
roadsides and waste ground.
Damp habitats, peaty and mineral soils, by streams, on lake
shores and marshy meadows.
Libertia formosa Chilean-iris Lake shores, along rivers and coastal cliffs.
Phormium tenax New Zealand Flax
Rhododendron ponticum* Rhododendron
Coastal habitats, on cliffs, waste ground, in dunes, damp
ground and by streams.
Drier lowland, upland bogs, rocky slopes, native and demesne
woodlands.
Rubus spectabilis Salmonberry Woodland, open ground, neglected gardens, and hedgerows.
Sarracenia purpurea Pitcherplant Bogs
Sasa palmata
Broad-leaved
Bamboo
Parks, demesnes and stream sides.
Senecio cineraria Silver Ragwort Cliffs, walls, railway banks and mainly coastal sites.
Sisyrinchium californicum Yellow-eyed-grass Marshy meadows, lake shores, damp grassland and ditches.
Spartina anglica* Common Cord-grass Intertidal mud fl ats
Stratiotes aloides Water-soldier Lakes, ditches and canals.
Table 1: Problematic terrestrial plant species
Information from the Habitat recorded in column, was obtained from Reynolds, S.C.P. (2002) A catalogue
of alien plants in Ireland. National Botanic Gardens, Glasnevin, Ireland.
Additional information on many of the Top 39 species in this booklet can be found on the Invasive Species
Ireland website: www.invasivespeciesireland.com which also has a colourful ‘Field Guide to Invasive
Species in Ireland’ available for download.