EPPO Global Database

EPPO Reporting Service no. 07 - 2002 Num. article: 2002/120

Invasive alien plants in United Kingdom

In United Kingdom, two web sites (parts are still under construction) give preliminary but useful information on invasive alien plant species which have already been introduced or which are perceived as potential threats. The Secretariat has added notes based on various British publications.

Invasive non-native terrestrial plant species
Acaena novae-zelandiae ** (Rosaceae) ;naturalized and increasing
Acer pseudoplatanus ** ( Aceraceae) ;long naturalized
Aegopodium podagraria * (Apiaceae) ;abundantly naturalized (old medicinal introduction)
Aster novae-angliae * (Asteraceae) ;naturalized
Aster novi belgii * (Asteraceae) ;naturalized
Brassica rapa (Brassicaceae) ;escape from cultivation
Buddleja davidii ** (Buddlejaceae) ;naturalized and increasing
Calystegia silvatica * (Convolvulaceae) ;widely naturalized, also hybridizes with C. sepium
Carpobrotus edulis ** (Aizoaceae) ;widely naturalized on cliffs in South
Crocosmia x crocosmiiflora ** (Iridaceae) ;naturalized, especially in south (cultivated plant)
Fuchsia magellanica * (Onagraceae) ;naturalized
Gaultheria shallon ** (Ericaceae) ;introduced as food for pheasants; locally abundant, naturalized
Gunnera tinctoria * (Gunneraceae) ;widely naturalized (but spreading mainly in Channel Islands; incidentally, also in Ireland)
Heracleum mantegazzianum *** (Apiaceae) ;naturalized and increasing
Hippophae rhamnoides ** (Elaeagnaceae) ;native; also widely planted and spreading
Hyacinthoides hispanica ** (Liliaceae) ;naturalized at scattered localities; hybridizes with H. non-scripta
Impatiens glandulifera *** (Balsaminaceae) ;naturalized and increasing on river banks in Centre and North
Lupinus arboreus ** (Fabaceae) ;escape from cultivation, planted to stabilize sand. Increasing in South and East
Matricaria discoidea (Asteraceae) ;widespread weed (rather than invasive)
Matteuccia struthiopteris (Woodsiaceae) ;occasionally naturalized in Scotland and North
Petasites fragrans * (Asteraceae) ;naturalized on waste ground
Prunus laurocerasus * (Rosaceae) ;widely planted, sometimes naturalized
Quercus cerris * ;(Fagaceae) ;widely planted, often naturalized
Quercus ilex ** (Fagaceae) ;well naturalized and locally becoming a threat to native vegetation
Reynoutria japonica *** (Polygonaceae) ;abundantly naturalized and increasing
Reynoutria sachalinensis ** (Polygonaceae) ;locally naturalized, increasing
Rhododendron luteum * (Ericaceae) ;garden escape, locally naturalized in Buckinghamshire, increasing
Rhododendron ponticum *** (Ericaceae) ;major threat to native vegetation
Senecio squalidus (Asteraceae) ;abundantly naturalized on waste ground (especially along railways)
Symphoricarpos albus * (Caprifoliaceae) ;locally naturalized

Invasive non-native aquatic plant species
Azolla filiculoides (Azollaceae) ;widely naturalized in South, but populations oscillable
Crassula helmsii (Crassulaceae) ;increasing rapidly and a threat to native vegetation
Eichhornia crassipes (Pontederiaceae) casual only
Elodea nuttalii (Hydrocharitaceae) ;widely naturalized, increasing and replacing the earlier invasive E. canadensis
Hydrocotyle ranunculoides (Apiaceae) ;locally naturalized
Lagarosiphon major (Hydrocharitaceae) ;scattered, naturalized
Lemna minuta (Lemnaceae) ;widely naturalized and increasing rapidly
Myriophyllum aquaticum (Haloragaceae) locally naturalized, increasing

Invasive aquatic plant species absent in UK
Ludwigia grandiflora (Onagraceae)
Salvinia molesta (Salviniaceae)
Trapa natans (Trapaceae)
*** Species considered as major problems
** ; Species considered as local or potential problems
* ; ; Species considered as potential problems
established: likely to remain
naturalized: established in native vegetation, appears native


Environment Agency (UK) - http://www.invasiveweeds.co.uk
Invasive Alien species project

Clement, E.J.; Foster, M.C. (1994) Alien plants of the British Isles, BSBI.
Stace, C. (1997) New flora of the British Isles (2nd edition), Cambridge University Press.