EPPO Global Database

EPPO Reporting Service no. 04 - 2009 Num. article: 2009/078

Invasive Alien Plants in European Macaronesia


The potential of invasiveness of 195 alien species (plants and animals) from European Macaronesia (Azores (PT), Madeira (PT) and the Islas Canarias (ES)) was assessed using two series of questions (table 1 & 2 below) about their noxiousness and feasibility of control:

Table 1: Measures of noxiousness, known and potential effect of IAS on native biodiversity and on natural and semi-natural habitats:
  • affected biodiversity value
  • impact on the affected biodiversity values
  • present status and trend of the invasion
  • invasive potential

Table 2: Measures of feasibility of control, probability of successful control or eradication
  • invasion traits
  • feasibility of control or eradication with available resources
  • support for control or eradication action
  • impact of control or eradication actions.

Each question was scored from 1 to 4 to allocate a final score to each species targeted. Several workshops with experts from all the archipelagos were organized, in order to standardize the attribution of scores. For each species, an average of the scores obtained in the different archipelagos was then calculated. The TOP 100 invasive species of European Macaronesia was determined among the 195 species under evaluation, and on the 100 most invasive species, 83 were plants.

For each species of the TOP 100, extensive information is provided on: morphology, distribution in the islands of European Macaronesia, habitats, general impacts on habitats and on other species, protected areas impacted, affected species and existing legislation.
The invasive alien plants included in the TOP 100 are listed below in the order of their scoring, with their origin, their occurrence in the EPPO region (checked against the EPPO and DAISIE databases), their general impacts on habitats and other species in European Macaronesia.
The following impacts were recorded and are indicated in the table as abbreviations (see brackets):
  • on habitats:
    • Changes in vegetation structure, or in the abundance of native or endemic species, or on the natural succession of native vegetation (structure, abundance, succession);
    • Other changes in the environment such as: hydrology, nutrient dynamics, light availability, changes in salinity, pH (other changes);
    • Alteration of the fire regime (fire regime);
    • Alterations on geomorphology such as: erosion rate, sedimentation rate (geomorphology).
  • on species:
    • Competition for space and resources (competition)
    • Impede or reduce the recruitment or the regeneration of endemic or native species (recruitment)
    • Facilitate the success of other invasive species (facilitate invasion)


Invasive Alien Plants among the top 25:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Carpobrotus edulis (Aizoaceae)
(EPPO List of Invasive Alien Plants)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ageratina adenophora (Asteraceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ulex europaeus (Fabaceae)
W & C-Eur.
Yes*
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Agave americana (Agavaceae)
Mexico
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Hedychium gardnerianum (Zingiberaceae)
India
Yes (only PT)
Geomorphology; Structure, abundance, succession; Other changes
Competition; Recruitment.
Cyrtomium falcatum (Dryopteridaceae)
S-Af., Asia, Pacif.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Pittosporum undulatum (Pittosporaceae)
SW Aus.
Yes (only PT)
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Opuntia ficus-indica (Cactaceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Salpichroa origanifolia (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Cytisus scoparius (Fabaceae)
S, C & C Eur.
Yes*
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Delairea odorata (Astercaeae)
(EPPO Alert List)
S- Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Hydrangea macrophylla (Hydrangeaceae)
Asia
Yes
Geomorphology; Structure, abundance, succession; Other changes
Competition; Recruitment.
Nicotiana glauca (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Opuntia stricta (Cacataceae)
N & C Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Eschscholzia californica (Papaveraceae)
N-Am.
Yes
Structure, abundance, succession; Other changes
Recruitment; Facilitate invasion
Adiantum raddianum (Adianthaceae)
C & S-Am.
No
Structure, abundance, succession
Competition; Recruitment.
Oxalis pes-caprae (Oxalidaceae)
(EPPO List of IAP)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Erigeron karvinskianus (Asteraceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Spartium junceum (Fabaceae)
S & W Eur.
Yes*
Structure, abundance, succession; Other changes
Competition; Recruitment.
Pennisetum setaceum (Poaceae) (EPPO Alert List)
NE Afr.
Yes
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Paraserianthes lophantha (Fabaceae)
Aus.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion



Invasive alien plants in the top 26-75:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Conyza canadensis (Asteraceae)
N-Am.
Yes
Structure, abundance, succession
Competition; Recruitment.
Conyza bonariensis (Asteraceae)
C & S Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Lantana camara (Verbenaceae)
C & S Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Aptenia cordifolia (Aizoaceae)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Solanum mauritianum (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Chasmanthe aethiopica (Iridaceae)
S-Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Tetragonia tetragonoides (Aizoaceae)
Asia, Aus., S-Am.
Yes
Structure, abundance, succession
Competition; Recruitment.
Cyathea cooperi (Cyatheaceae)
NW Aus.
No
Structure, abundance, succession; Other changes
Competition; Recruitment.
Symphyotrichum subulatum (Asteraceae)
N, C & S Am.
No
Structure, abundance, succession
Competition; Recruitment.
Ipomoea indica (Convolvulaceae)
Pantrop.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Tradescantia fluminensis (Commelinaceae)
Brasil
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Drosanthemum floribundum (Aizoaceae)
S-Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Stenotaphrum secundatum (Poaceae)
W Af., Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Ageratina riparia (Asteraceae)
Mexico
No
Structure, abundance, succession
Competition; Recruitment.
Acacia melanoxylon (Fabaceae)
Aus.
Yes
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Doodia caudata (Blechnaceae)
Aus.
No
Structure, abundance, succession
Competition; Recruitment.
Nassella neesiana (Poaceae)
S-Am.
Yes (only ES)
Structure, abundance, succession
Competition; Recruitment.
Colocasia esculenta (Araceae)
Malaysia
No
Structure, abundance, succession; Other changes
Competition; Recruitment.
Eucalyptus globulus (Myrtaceae)
Aus.
Yes
Geomorphology; Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Anredera cordifolia (Basellaceae)
S-Am.
Yes
Structure, abundance, succession
Competition; Facilitate invasion
Phytolacca americana (Phytolaccaceae)
N-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Adiantum hispidulum (Adianthaceae)
SW Af.
No
Structure, abundance, succession
Competition; Recruitment.
Leycesteria formosa (Caprifoliaceae)
India, SW China
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Cardiospermum grandiflorum (Sapindaceae)
Am., W India, Af.
Yes (only IT)
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ricinus communis (Euphorbiaceae)
Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Ailanthus altissima (Simaroubaceae)
China
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion; Allelopathy
Bidens pilosa (Asteraceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Centranthus ruber (Valerianaceae)
Medit.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion
Tropaeolum majus (Tropaeolaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Pelargonium inquinans (Geraniaceae)
S-Af.
Yes (only FR)
Structure, abundance, succession
Competition; Recruitment
Opuntia tuna (Cactaceae)
Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Gunnera tinctoria (Gunneraceae)
WS Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Phormium tenax (Hemerocallidaceae)
NZ
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Egeria densa (Hydrocharitaceae) (EPPO List of IAP)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Gomphocarpus fruticosus (Asclepiadaceae)
Af.
Yes
Structure, abundance, succession
Competition; Recruitment
Cytisus striatus (Fabaceae)
Iberia, N-Af.
Yes
Fire regime; Structure, abundance, succession
Competition; Recruitment
Nicotiana paniculata (Solanaceae)
Am.
No
Structure, abundance, succession
Competition
Cotula australis (Astercaeae)
Aus, NZ
Yes
Structure, abundance, succession
Competition
Crassula multicava (Crassulaceae)
S-Af.
Yes (only ES)
Structure, abundance, succession
Competition
Deparia petersenii (Dryopteridaceae)
Asia
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Araujia sericifera (Asclepiadaceae) (EPPO Alert List)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition



Invasive alien plants in the top 76-100:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Cirsium vulgare (Asteraceae)
Eurasia, N-Af.
Yes*
Structure, abundance, succession
Competition; Recruitment
Solanum bonariense (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Crassula tillaea (Crassulaceae)
S-Af.
Yes
Structure, abundance, succession
Recruitment
Acacia saligna (Fabaceae)
Aus
Yes
Structure, abundance, succession; Other changes
Competition; Facilitate invasion
Solanum lycopersicum var. lycopersicum (Solanaceae)
Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Nephrolepis cordifolia (Lomariopsidaceae)
Pantrop, Himal., Aus
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Pennisetum clandestinum (Poaceae)
W-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Hedychium coronarium (Zingiberaceae)
SE Asia
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Passiflora tripartita (Passifloraceae)
S-Am.
No
Structure, abundance, succession
Competition; Recruitment
Paspalum distichum (Poaceae)
Am.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion
Coronopus didymus (Brassicaceae)
S-Am.
Yes
Structure, abundance, succession
Competition
Conyza floribunda (Asteraceae)
S-Am.
Yes
Structure, abundance, succession
Competition; Recruitment
Pinus pinaster (Pinaceae)
S-Eur.
Yes*
Structure, abundance, succession
Competition; Recruitment
Soleirolia soleirolii (Urticaceae)
Corse, Sardinia, Baleares
Yes
Structure, abundance, succession
Competition; Recruitment
Agapanthus praecox (Agapanthaceae)
S-Af.
Yes (only UK)
Structure, abundance, succession
Competition; Recruitment
Duchesnea indica (Rosaceae)
Asia
Yes
Structure, abundance, succession
Recruitment
Crocosmia x crocosmiflora (Iridaceae)
Hybrid
Yes
Structure, abundance, succession
Competition; Recruitment
Aloe vera (Aloaceae)
NE Af.
Yes
Structure, abundance, succession
Competition; Recruitment
Leptospermum scoparium (Myrtaceae)
Aus, NZ
Yes (only UK)
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment
Ulex minor (Fabaceae)
W Eur.
Yes, ind
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Wigandia urens (Hydrophyllaceae)
C & S Am.
Yes
Structure, abundance, succession
Competition; Recruitment

________
*: the species in indigenous at least in part of the EPPO region.The potential of invasiveness of 195 alien species (plants and animals) from European Macaronesia (Azores (PT), Madeira (PT) and the Islas Canarias (ES)) was assessed using two series of questions (table 1 & 2 below) about their noxiousness and feasibility of control:

Table 1: Measures of noxiousness, known and potential effect of IAS on native biodiversity and on natural and semi-natural habitats:
  • affected biodiversity value
  • impact on the affected biodiversity values
  • present status and trend of the invasion
  • invasive potential

Table 2: Measures of feasibility of control, probability of successful control or eradication
  • invasion traits
  • feasibility of control or eradication with available resources
  • support for control or eradication action
  • impact of control or eradication actions.

Each question was scored from 1 to 4 to allocate a final score to each species targeted. Several workshops with experts from all the archipelagos were organized, in order to standardize the attribution of scores. For each species, an average of the scores obtained in the different archipelagos was then calculated. The TOP 100 invasive species of European Macaronesia was determined among the 195 species under evaluation, and on the 100 most invasive species, 83 were plants.

For each species of the TOP 100, extensive information is provided on: morphology, distribution in the islands of European Macaronesia, habitats, general impacts on habitats and on other species, protected areas impacted, affected species and existing legislation.
The invasive alien plants included in the TOP 100 are listed below in the order of their scoring, with their origin, their occurrence in the EPPO region (checked against the EPPO and DAISIE databases), their general impacts on habitats and other species in European Macaronesia.
The following impacts were recorded and are indicated in the table as abbreviations (see brackets):
  • on habitats:
    • Changes in vegetation structure, or in the abundance of native or endemic species, or on the natural succession of native vegetation (structure, abundance, succession);
    • Other changes in the environment such as: hydrology, nutrient dynamics, light availability, changes in salinity, pH (other changes);
    • Alteration of the fire regime (fire regime);
    • Alterations on geomorphology such as: erosion rate, sedimentation rate (geomorphology).
  • on species:
    • Competition for space and resources (competition)
    • Impede or reduce the recruitment or the regeneration of endemic or native species (recruitment)
    • Facilitate the success of other invasive species (facilitate invasion)


Invasive Alien Plants among the top 25:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Carpobrotus edulis (Aizoaceae)
(EPPO List of Invasive Alien Plants)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ageratina adenophora (Asteraceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ulex europaeus (Fabaceae)
W & C-Eur.
Yes*
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Agave americana (Agavaceae)
Mexico
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Hedychium gardnerianum (Zingiberaceae)
India
Yes (only PT)
Geomorphology; Structure, abundance, succession; Other changes
Competition; Recruitment.
Cyrtomium falcatum (Dryopteridaceae)
S-Af., Asia, Pacif.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Pittosporum undulatum (Pittosporaceae)
SW Aus.
Yes (only PT)
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Opuntia ficus-indica (Cactaceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Salpichroa origanifolia (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Cytisus scoparius (Fabaceae)
S, C & C Eur.
Yes*
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Delairea odorata (Astercaeae)
(EPPO Alert List)
S- Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Hydrangea macrophylla (Hydrangeaceae)
Asia
Yes
Geomorphology; Structure, abundance, succession; Other changes
Competition; Recruitment.
Nicotiana glauca (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Opuntia stricta (Cacataceae)
N & C Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Eschscholzia californica (Papaveraceae)
N-Am.
Yes
Structure, abundance, succession; Other changes
Recruitment; Facilitate invasion
Adiantum raddianum (Adianthaceae)
C & S-Am.
No
Structure, abundance, succession
Competition; Recruitment.
Oxalis pes-caprae (Oxalidaceae)
(EPPO List of IAP)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Erigeron karvinskianus (Asteraceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Spartium junceum (Fabaceae)
S & W Eur.
Yes*
Structure, abundance, succession; Other changes
Competition; Recruitment.
Pennisetum setaceum (Poaceae) (EPPO Alert List)
NE Afr.
Yes
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Paraserianthes lophantha (Fabaceae)
Aus.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion



Invasive alien plants in the top 26-75:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Conyza canadensis (Asteraceae)
N-Am.
Yes
Structure, abundance, succession
Competition; Recruitment.
Conyza bonariensis (Asteraceae)
C & S Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Lantana camara (Verbenaceae)
C & S Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Aptenia cordifolia (Aizoaceae)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Solanum mauritianum (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Chasmanthe aethiopica (Iridaceae)
S-Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Tetragonia tetragonoides (Aizoaceae)
Asia, Aus., S-Am.
Yes
Structure, abundance, succession
Competition; Recruitment.
Cyathea cooperi (Cyatheaceae)
NW Aus.
No
Structure, abundance, succession; Other changes
Competition; Recruitment.
Symphyotrichum subulatum (Asteraceae)
N, C & S Am.
No
Structure, abundance, succession
Competition; Recruitment.
Ipomoea indica (Convolvulaceae)
Pantrop.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Tradescantia fluminensis (Commelinaceae)
Brasil
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Drosanthemum floribundum (Aizoaceae)
S-Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Stenotaphrum secundatum (Poaceae)
W Af., Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Ageratina riparia (Asteraceae)
Mexico
No
Structure, abundance, succession
Competition; Recruitment.
Acacia melanoxylon (Fabaceae)
Aus.
Yes
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Doodia caudata (Blechnaceae)
Aus.
No
Structure, abundance, succession
Competition; Recruitment.
Nassella neesiana (Poaceae)
S-Am.
Yes (only ES)
Structure, abundance, succession
Competition; Recruitment.
Colocasia esculenta (Araceae)
Malaysia
No
Structure, abundance, succession; Other changes
Competition; Recruitment.
Eucalyptus globulus (Myrtaceae)
Aus.
Yes
Geomorphology; Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Anredera cordifolia (Basellaceae)
S-Am.
Yes
Structure, abundance, succession
Competition; Facilitate invasion
Phytolacca americana (Phytolaccaceae)
N-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Adiantum hispidulum (Adianthaceae)
SW Af.
No
Structure, abundance, succession
Competition; Recruitment.
Leycesteria formosa (Caprifoliaceae)
India, SW China
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Cardiospermum grandiflorum (Sapindaceae)
Am., W India, Af.
Yes (only IT)
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ricinus communis (Euphorbiaceae)
Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Ailanthus altissima (Simaroubaceae)
China
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion; Allelopathy
Bidens pilosa (Asteraceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Centranthus ruber (Valerianaceae)
Medit.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion
Tropaeolum majus (Tropaeolaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Pelargonium inquinans (Geraniaceae)
S-Af.
Yes (only FR)
Structure, abundance, succession
Competition; Recruitment
Opuntia tuna (Cactaceae)
Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Gunnera tinctoria (Gunneraceae)
WS Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Phormium tenax (Hemerocallidaceae)
NZ
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Egeria densa (Hydrocharitaceae) (EPPO List of IAP)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Gomphocarpus fruticosus (Asclepiadaceae)
Af.
Yes
Structure, abundance, succession
Competition; Recruitment
Cytisus striatus (Fabaceae)
Iberia, N-Af.
Yes
Fire regime; Structure, abundance, succession
Competition; Recruitment
Nicotiana paniculata (Solanaceae)
Am.
No
Structure, abundance, succession
Competition
Cotula australis (Astercaeae)
Aus, NZ
Yes
Structure, abundance, succession
Competition
Crassula multicava (Crassulaceae)
S-Af.
Yes (only ES)
Structure, abundance, succession
Competition
Deparia petersenii (Dryopteridaceae)
Asia
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Araujia sericifera (Asclepiadaceae) (EPPO Alert List)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition



Invasive alien plants in the top 76-100:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Cirsium vulgare (Asteraceae)
Eurasia, N-Af.
Yes*
Structure, abundance, succession
Competition; Recruitment
Solanum bonariense (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Crassula tillaea (Crassulaceae)
S-Af.
Yes
Structure, abundance, succession
Recruitment
Acacia saligna (Fabaceae)
Aus
Yes
Structure, abundance, succession; Other changes
Competition; Facilitate invasion
Solanum lycopersicum var. lycopersicum (Solanaceae)
Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Nephrolepis cordifolia (Lomariopsidaceae)
Pantrop, Himal., Aus
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Pennisetum clandestinum (Poaceae)
W-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Hedychium coronarium (Zingiberaceae)
SE Asia
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Passiflora tripartita (Passifloraceae)
S-Am.
No
Structure, abundance, succession
Competition; Recruitment
Paspalum distichum (Poaceae)
Am.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion
Coronopus didymus (Brassicaceae)
S-Am.
Yes
Structure, abundance, succession
Competition
Conyza floribunda (Asteraceae)
S-Am.
Yes
Structure, abundance, succession
Competition; Recruitment
Pinus pinaster (Pinaceae)
S-Eur.
Yes*
Structure, abundance, succession
Competition; Recruitment
Soleirolia soleirolii (Urticaceae)
Corse, Sardinia, Baleares
Yes
Structure, abundance, succession
Competition; Recruitment
Agapanthus praecox (Agapanthaceae)
S-Af.
Yes (only UK)
Structure, abundance, succession
Competition; Recruitment
Duchesnea indica (Rosaceae)
Asia
Yes
Structure, abundance, succession
Recruitment
Crocosmia x crocosmiflora (Iridaceae)
Hybrid
Yes
Structure, abundance, succession
Competition; Recruitment
Aloe vera (Aloaceae)
NE Af.
Yes
Structure, abundance, succession
Competition; Recruitment
Leptospermum scoparium (Myrtaceae)
Aus, NZ
Yes (only UK)
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment
Ulex minor (Fabaceae)
W Eur.
Yes, ind
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Wigandia urens (Hydrophyllaceae)
C & S Am.
Yes
Structure, abundance, succession
Competition; Recruitment

________
*: the species in indigenous at least in part of the EPPO region.The potential of invasiveness of 195 alien species (plants and animals) from European Macaronesia (Azores (PT), Madeira (PT) and the Islas Canarias (ES)) was assessed using two series of questions (table 1 & 2 below) about their noxiousness and feasibility of control:

Table 1: Measures of noxiousness, known and potential effect of IAS on native biodiversity and on natural and semi-natural habitats:
  • affected biodiversity value
  • impact on the affected biodiversity values
  • present status and trend of the invasion
  • invasive potential

Table 2: Measures of feasibility of control, probability of successful control or eradication
  • invasion traits
  • feasibility of control or eradication with available resources
  • support for control or eradication action
  • impact of control or eradication actions.

Each question was scored from 1 to 4 to allocate a final score to each species targeted. Several workshops with experts from all the archipelagos were organized, in order to standardize the attribution of scores. For each species, an average of the scores obtained in the different archipelagos was then calculated. The TOP 100 invasive species of European Macaronesia was determined among the 195 species under evaluation, and on the 100 most invasive species, 83 were plants.

For each species of the TOP 100, extensive information is provided on: morphology, distribution in the islands of European Macaronesia, habitats, general impacts on habitats and on other species, protected areas impacted, affected species and existing legislation.
The invasive alien plants included in the TOP 100 are listed below in the order of their scoring, with their origin, their occurrence in the EPPO region (checked against the EPPO and DAISIE databases), their general impacts on habitats and other species in European Macaronesia.
The following impacts were recorded and are indicated in the table as abbreviations (see brackets):
  • on habitats:
    • Changes in vegetation structure, or in the abundance of native or endemic species, or on the natural succession of native vegetation (structure, abundance, succession);
    • Other changes in the environment such as: hydrology, nutrient dynamics, light availability, changes in salinity, pH (other changes);
    • Alteration of the fire regime (fire regime);
    • Alterations on geomorphology such as: erosion rate, sedimentation rate (geomorphology).
  • on species:
    • Competition for space and resources (competition)
    • Impede or reduce the recruitment or the regeneration of endemic or native species (recruitment)
    • Facilitate the success of other invasive species (facilitate invasion)


Invasive Alien Plants among the top 25:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Carpobrotus edulis (Aizoaceae)
(EPPO List of Invasive Alien Plants)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ageratina adenophora (Asteraceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ulex europaeus (Fabaceae)
W & C-Eur.
Yes*
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Agave americana (Agavaceae)
Mexico
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Hedychium gardnerianum (Zingiberaceae)
India
Yes (only PT)
Geomorphology; Structure, abundance, succession; Other changes
Competition; Recruitment.
Cyrtomium falcatum (Dryopteridaceae)
S-Af., Asia, Pacif.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Pittosporum undulatum (Pittosporaceae)
SW Aus.
Yes (only PT)
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Opuntia ficus-indica (Cactaceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Salpichroa origanifolia (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Cytisus scoparius (Fabaceae)
S, C & C Eur.
Yes*
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Delairea odorata (Astercaeae)
(EPPO Alert List)
S- Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Hydrangea macrophylla (Hydrangeaceae)
Asia
Yes
Geomorphology; Structure, abundance, succession; Other changes
Competition; Recruitment.
Nicotiana glauca (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Opuntia stricta (Cacataceae)
N & C Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Eschscholzia californica (Papaveraceae)
N-Am.
Yes
Structure, abundance, succession; Other changes
Recruitment; Facilitate invasion
Adiantum raddianum (Adianthaceae)
C & S-Am.
No
Structure, abundance, succession
Competition; Recruitment.
Oxalis pes-caprae (Oxalidaceae)
(EPPO List of IAP)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Erigeron karvinskianus (Asteraceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Spartium junceum (Fabaceae)
S & W Eur.
Yes*
Structure, abundance, succession; Other changes
Competition; Recruitment.
Pennisetum setaceum (Poaceae) (EPPO Alert List)
NE Afr.
Yes
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Paraserianthes lophantha (Fabaceae)
Aus.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion



Invasive alien plants in the top 26-75:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Conyza canadensis (Asteraceae)
N-Am.
Yes
Structure, abundance, succession
Competition; Recruitment.
Conyza bonariensis (Asteraceae)
C & S Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Lantana camara (Verbenaceae)
C & S Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Aptenia cordifolia (Aizoaceae)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Solanum mauritianum (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Chasmanthe aethiopica (Iridaceae)
S-Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Tetragonia tetragonoides (Aizoaceae)
Asia, Aus., S-Am.
Yes
Structure, abundance, succession
Competition; Recruitment.
Cyathea cooperi (Cyatheaceae)
NW Aus.
No
Structure, abundance, succession; Other changes
Competition; Recruitment.
Symphyotrichum subulatum (Asteraceae)
N, C & S Am.
No
Structure, abundance, succession
Competition; Recruitment.
Ipomoea indica (Convolvulaceae)
Pantrop.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Tradescantia fluminensis (Commelinaceae)
Brasil
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Drosanthemum floribundum (Aizoaceae)
S-Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Stenotaphrum secundatum (Poaceae)
W Af., Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Ageratina riparia (Asteraceae)
Mexico
No
Structure, abundance, succession
Competition; Recruitment.
Acacia melanoxylon (Fabaceae)
Aus.
Yes
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Doodia caudata (Blechnaceae)
Aus.
No
Structure, abundance, succession
Competition; Recruitment.
Nassella neesiana (Poaceae)
S-Am.
Yes (only ES)
Structure, abundance, succession
Competition; Recruitment.
Colocasia esculenta (Araceae)
Malaysia
No
Structure, abundance, succession; Other changes
Competition; Recruitment.
Eucalyptus globulus (Myrtaceae)
Aus.
Yes
Geomorphology; Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Anredera cordifolia (Basellaceae)
S-Am.
Yes
Structure, abundance, succession
Competition; Facilitate invasion
Phytolacca americana (Phytolaccaceae)
N-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Adiantum hispidulum (Adianthaceae)
SW Af.
No
Structure, abundance, succession
Competition; Recruitment.
Leycesteria formosa (Caprifoliaceae)
India, SW China
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Cardiospermum grandiflorum (Sapindaceae)
Am., W India, Af.
Yes (only IT)
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ricinus communis (Euphorbiaceae)
Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Ailanthus altissima (Simaroubaceae)
China
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion; Allelopathy
Bidens pilosa (Asteraceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Centranthus ruber (Valerianaceae)
Medit.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion
Tropaeolum majus (Tropaeolaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Pelargonium inquinans (Geraniaceae)
S-Af.
Yes (only FR)
Structure, abundance, succession
Competition; Recruitment
Opuntia tuna (Cactaceae)
Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Gunnera tinctoria (Gunneraceae)
WS Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Phormium tenax (Hemerocallidaceae)
NZ
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Egeria densa (Hydrocharitaceae) (EPPO List of IAP)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Gomphocarpus fruticosus (Asclepiadaceae)
Af.
Yes
Structure, abundance, succession
Competition; Recruitment
Cytisus striatus (Fabaceae)
Iberia, N-Af.
Yes
Fire regime; Structure, abundance, succession
Competition; Recruitment
Nicotiana paniculata (Solanaceae)
Am.
No
Structure, abundance, succession
Competition
Cotula australis (Astercaeae)
Aus, NZ
Yes
Structure, abundance, succession
Competition
Crassula multicava (Crassulaceae)
S-Af.
Yes (only ES)
Structure, abundance, succession
Competition
Deparia petersenii (Dryopteridaceae)
Asia
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Araujia sericifera (Asclepiadaceae) (EPPO Alert List)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition



Invasive alien plants in the top 76-100:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Cirsium vulgare (Asteraceae)
Eurasia, N-Af.
Yes*
Structure, abundance, succession
Competition; Recruitment
Solanum bonariense (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Crassula tillaea (Crassulaceae)
S-Af.
Yes
Structure, abundance, succession
Recruitment
Acacia saligna (Fabaceae)
Aus
Yes
Structure, abundance, succession; Other changes
Competition; Facilitate invasion
Solanum lycopersicum var. lycopersicum (Solanaceae)
Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Nephrolepis cordifolia (Lomariopsidaceae)
Pantrop, Himal., Aus
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Pennisetum clandestinum (Poaceae)
W-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Hedychium coronarium (Zingiberaceae)
SE Asia
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Passiflora tripartita (Passifloraceae)
S-Am.
No
Structure, abundance, succession
Competition; Recruitment
Paspalum distichum (Poaceae)
Am.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion
Coronopus didymus (Brassicaceae)
S-Am.
Yes
Structure, abundance, succession
Competition
Conyza floribunda (Asteraceae)
S-Am.
Yes
Structure, abundance, succession
Competition; Recruitment
Pinus pinaster (Pinaceae)
S-Eur.
Yes*
Structure, abundance, succession
Competition; Recruitment
Soleirolia soleirolii (Urticaceae)
Corse, Sardinia, Baleares
Yes
Structure, abundance, succession
Competition; Recruitment
Agapanthus praecox (Agapanthaceae)
S-Af.
Yes (only UK)
Structure, abundance, succession
Competition; Recruitment
Duchesnea indica (Rosaceae)
Asia
Yes
Structure, abundance, succession
Recruitment
Crocosmia x crocosmiflora (Iridaceae)
Hybrid
Yes
Structure, abundance, succession
Competition; Recruitment
Aloe vera (Aloaceae)
NE Af.
Yes
Structure, abundance, succession
Competition; Recruitment
Leptospermum scoparium (Myrtaceae)
Aus, NZ
Yes (only UK)
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment
Ulex minor (Fabaceae)
W Eur.
Yes, ind
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Wigandia urens (Hydrophyllaceae)
C & S Am.
Yes
Structure, abundance, succession
Competition; Recruitment

________
*: the species in indigenous at least in part of the EPPO region.The potential of invasiveness of 195 alien species (plants and animals) from European Macaronesia (Azores (PT), Madeira (PT) and the Islas Canarias (ES)) was assessed using two series of questions (table 1 & 2 below) about their noxiousness and feasibility of control:

Table 1: Measures of noxiousness, known and potential effect of IAS on native biodiversity and on natural and semi-natural habitats:
  • affected biodiversity value
  • impact on the affected biodiversity values
  • present status and trend of the invasion
  • invasive potential

Table 2: Measures of feasibility of control, probability of successful control or eradication
  • invasion traits
  • feasibility of control or eradication with available resources
  • support for control or eradication action
  • impact of control or eradication actions.

Each question was scored from 1 to 4 to allocate a final score to each species targeted. Several workshops with experts from all the archipelagos were organized, in order to standardize the attribution of scores. For each species, an average of the scores obtained in the different archipelagos was then calculated. The TOP 100 invasive species of European Macaronesia was determined among the 195 species under evaluation, and on the 100 most invasive species, 83 were plants.

For each species of the TOP 100, extensive information is provided on: morphology, distribution in the islands of European Macaronesia, habitats, general impacts on habitats and on other species, protected areas impacted, affected species and existing legislation.
The invasive alien plants included in the TOP 100 are listed below in the order of their scoring, with their origin, their occurrence in the EPPO region (checked against the EPPO and DAISIE databases), their general impacts on habitats and other species in European Macaronesia.
The following impacts were recorded and are indicated in the table as abbreviations (see brackets):
  • on habitats:
    • Changes in vegetation structure, or in the abundance of native or endemic species, or on the natural succession of native vegetation (structure, abundance, succession);
    • Other changes in the environment such as: hydrology, nutrient dynamics, light availability, changes in salinity, pH (other changes);
    • Alteration of the fire regime (fire regime);
    • Alterations on geomorphology such as: erosion rate, sedimentation rate (geomorphology).
  • on species:
    • Competition for space and resources (competition)
    • Impede or reduce the recruitment or the regeneration of endemic or native species (recruitment)
    • Facilitate the success of other invasive species (facilitate invasion)


Invasive Alien Plants among the top 25:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Carpobrotus edulis (Aizoaceae)
(EPPO List of Invasive Alien Plants)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ageratina adenophora (Asteraceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ulex europaeus (Fabaceae)
W & C-Eur.
Yes*
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Agave americana (Agavaceae)
Mexico
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Hedychium gardnerianum (Zingiberaceae)
India
Yes (only PT)
Geomorphology; Structure, abundance, succession; Other changes
Competition; Recruitment.
Cyrtomium falcatum (Dryopteridaceae)
S-Af., Asia, Pacif.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Pittosporum undulatum (Pittosporaceae)
SW Aus.
Yes (only PT)
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Opuntia ficus-indica (Cactaceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Salpichroa origanifolia (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Cytisus scoparius (Fabaceae)
S, C & C Eur.
Yes*
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Delairea odorata (Astercaeae)
(EPPO Alert List)
S- Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Hydrangea macrophylla (Hydrangeaceae)
Asia
Yes
Geomorphology; Structure, abundance, succession; Other changes
Competition; Recruitment.
Nicotiana glauca (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Opuntia stricta (Cacataceae)
N & C Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Eschscholzia californica (Papaveraceae)
N-Am.
Yes
Structure, abundance, succession; Other changes
Recruitment; Facilitate invasion
Adiantum raddianum (Adianthaceae)
C & S-Am.
No
Structure, abundance, succession
Competition; Recruitment.
Oxalis pes-caprae (Oxalidaceae)
(EPPO List of IAP)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Erigeron karvinskianus (Asteraceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Spartium junceum (Fabaceae)
S & W Eur.
Yes*
Structure, abundance, succession; Other changes
Competition; Recruitment.
Pennisetum setaceum (Poaceae) (EPPO Alert List)
NE Afr.
Yes
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Paraserianthes lophantha (Fabaceae)
Aus.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion



Invasive alien plants in the top 26-75:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Conyza canadensis (Asteraceae)
N-Am.
Yes
Structure, abundance, succession
Competition; Recruitment.
Conyza bonariensis (Asteraceae)
C & S Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Lantana camara (Verbenaceae)
C & S Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Aptenia cordifolia (Aizoaceae)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Solanum mauritianum (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Chasmanthe aethiopica (Iridaceae)
S-Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Tetragonia tetragonoides (Aizoaceae)
Asia, Aus., S-Am.
Yes
Structure, abundance, succession
Competition; Recruitment.
Cyathea cooperi (Cyatheaceae)
NW Aus.
No
Structure, abundance, succession; Other changes
Competition; Recruitment.
Symphyotrichum subulatum (Asteraceae)
N, C & S Am.
No
Structure, abundance, succession
Competition; Recruitment.
Ipomoea indica (Convolvulaceae)
Pantrop.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Tradescantia fluminensis (Commelinaceae)
Brasil
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Drosanthemum floribundum (Aizoaceae)
S-Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Stenotaphrum secundatum (Poaceae)
W Af., Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Ageratina riparia (Asteraceae)
Mexico
No
Structure, abundance, succession
Competition; Recruitment.
Acacia melanoxylon (Fabaceae)
Aus.
Yes
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Doodia caudata (Blechnaceae)
Aus.
No
Structure, abundance, succession
Competition; Recruitment.
Nassella neesiana (Poaceae)
S-Am.
Yes (only ES)
Structure, abundance, succession
Competition; Recruitment.
Colocasia esculenta (Araceae)
Malaysia
No
Structure, abundance, succession; Other changes
Competition; Recruitment.
Eucalyptus globulus (Myrtaceae)
Aus.
Yes
Geomorphology; Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Anredera cordifolia (Basellaceae)
S-Am.
Yes
Structure, abundance, succession
Competition; Facilitate invasion
Phytolacca americana (Phytolaccaceae)
N-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Adiantum hispidulum (Adianthaceae)
SW Af.
No
Structure, abundance, succession
Competition; Recruitment.
Leycesteria formosa (Caprifoliaceae)
India, SW China
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Cardiospermum grandiflorum (Sapindaceae)
Am., W India, Af.
Yes (only IT)
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ricinus communis (Euphorbiaceae)
Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Ailanthus altissima (Simaroubaceae)
China
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion; Allelopathy
Bidens pilosa (Asteraceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Centranthus ruber (Valerianaceae)
Medit.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion
Tropaeolum majus (Tropaeolaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Pelargonium inquinans (Geraniaceae)
S-Af.
Yes (only FR)
Structure, abundance, succession
Competition; Recruitment
Opuntia tuna (Cactaceae)
Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Gunnera tinctoria (Gunneraceae)
WS Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Phormium tenax (Hemerocallidaceae)
NZ
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Egeria densa (Hydrocharitaceae) (EPPO List of IAP)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Gomphocarpus fruticosus (Asclepiadaceae)
Af.
Yes
Structure, abundance, succession
Competition; Recruitment
Cytisus striatus (Fabaceae)
Iberia, N-Af.
Yes
Fire regime; Structure, abundance, succession
Competition; Recruitment
Nicotiana paniculata (Solanaceae)
Am.
No
Structure, abundance, succession
Competition
Cotula australis (Astercaeae)
Aus, NZ
Yes
Structure, abundance, succession
Competition
Crassula multicava (Crassulaceae)
S-Af.
Yes (only ES)
Structure, abundance, succession
Competition
Deparia petersenii (Dryopteridaceae)
Asia
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Araujia sericifera (Asclepiadaceae) (EPPO Alert List)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition



Invasive alien plants in the top 76-100:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Cirsium vulgare (Asteraceae)
Eurasia, N-Af.
Yes*
Structure, abundance, succession
Competition; Recruitment
Solanum bonariense (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Crassula tillaea (Crassulaceae)
S-Af.
Yes
Structure, abundance, succession
Recruitment
Acacia saligna (Fabaceae)
Aus
Yes
Structure, abundance, succession; Other changes
Competition; Facilitate invasion
Solanum lycopersicum var. lycopersicum (Solanaceae)
Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Nephrolepis cordifolia (Lomariopsidaceae)
Pantrop, Himal., Aus
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Pennisetum clandestinum (Poaceae)
W-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Hedychium coronarium (Zingiberaceae)
SE Asia
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Passiflora tripartita (Passifloraceae)
S-Am.
No
Structure, abundance, succession
Competition; Recruitment
Paspalum distichum (Poaceae)
Am.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion
Coronopus didymus (Brassicaceae)
S-Am.
Yes
Structure, abundance, succession
Competition
Conyza floribunda (Asteraceae)
S-Am.
Yes
Structure, abundance, succession
Competition; Recruitment
Pinus pinaster (Pinaceae)
S-Eur.
Yes*
Structure, abundance, succession
Competition; Recruitment
Soleirolia soleirolii (Urticaceae)
Corse, Sardinia, Baleares
Yes
Structure, abundance, succession
Competition; Recruitment
Agapanthus praecox (Agapanthaceae)
S-Af.
Yes (only UK)
Structure, abundance, succession
Competition; Recruitment
Duchesnea indica (Rosaceae)
Asia
Yes
Structure, abundance, succession
Recruitment
Crocosmia x crocosmiflora (Iridaceae)
Hybrid
Yes
Structure, abundance, succession
Competition; Recruitment
Aloe vera (Aloaceae)
NE Af.
Yes
Structure, abundance, succession
Competition; Recruitment
Leptospermum scoparium (Myrtaceae)
Aus, NZ
Yes (only UK)
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment
Ulex minor (Fabaceae)
W Eur.
Yes, ind
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Wigandia urens (Hydrophyllaceae)
C & S Am.
Yes
Structure, abundance, succession
Competition; Recruitment

________
*: the species in indigenous at least in part of the EPPO region.The potential of invasiveness of 195 alien species (plants and animals) from European Macaronesia (Azores (PT), Madeira (PT) and the Islas Canarias (ES)) was assessed using two series of questions (table 1 & 2 below) about their noxiousness and feasibility of control:

Table 1: Measures of noxiousness, known and potential effect of IAS on native biodiversity and on natural and semi-natural habitats:
  • affected biodiversity value
  • impact on the affected biodiversity values
  • present status and trend of the invasion
  • invasive potential

Table 2: Measures of feasibility of control, probability of successful control or eradication
  • invasion traits
  • feasibility of control or eradication with available resources
  • support for control or eradication action
  • impact of control or eradication actions.

Each question was scored from 1 to 4 to allocate a final score to each species targeted. Several workshops with experts from all the archipelagos were organized, in order to standardize the attribution of scores. For each species, an average of the scores obtained in the different archipelagos was then calculated. The TOP 100 invasive species of European Macaronesia was determined among the 195 species under evaluation, and on the 100 most invasive species, 83 were plants.

For each species of the TOP 100, extensive information is provided on: morphology, distribution in the islands of European Macaronesia, habitats, general impacts on habitats and on other species, protected areas impacted, affected species and existing legislation.
The invasive alien plants included in the TOP 100 are listed below in the order of their scoring, with their origin, their occurrence in the EPPO region (checked against the EPPO and DAISIE databases), their general impacts on habitats and other species in European Macaronesia.
The following impacts were recorded and are indicated in the table as abbreviations (see brackets):
  • on habitats:
    • Changes in vegetation structure, or in the abundance of native or endemic species, or on the natural succession of native vegetation (structure, abundance, succession);
    • Other changes in the environment such as: hydrology, nutrient dynamics, light availability, changes in salinity, pH (other changes);
    • Alteration of the fire regime (fire regime);
    • Alterations on geomorphology such as: erosion rate, sedimentation rate (geomorphology).
  • on species:
    • Competition for space and resources (competition)
    • Impede or reduce the recruitment or the regeneration of endemic or native species (recruitment)
    • Facilitate the success of other invasive species (facilitate invasion)


Invasive Alien Plants among the top 25:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Carpobrotus edulis (Aizoaceae)
(EPPO List of Invasive Alien Plants)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ageratina adenophora (Asteraceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ulex europaeus (Fabaceae)
W & C-Eur.
Yes*
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Agave americana (Agavaceae)
Mexico
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Hedychium gardnerianum (Zingiberaceae)
India
Yes (only PT)
Geomorphology; Structure, abundance, succession; Other changes
Competition; Recruitment.
Cyrtomium falcatum (Dryopteridaceae)
S-Af., Asia, Pacif.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Pittosporum undulatum (Pittosporaceae)
SW Aus.
Yes (only PT)
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Opuntia ficus-indica (Cactaceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Salpichroa origanifolia (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Cytisus scoparius (Fabaceae)
S, C & C Eur.
Yes*
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Delairea odorata (Astercaeae)
(EPPO Alert List)
S- Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Hydrangea macrophylla (Hydrangeaceae)
Asia
Yes
Geomorphology; Structure, abundance, succession; Other changes
Competition; Recruitment.
Nicotiana glauca (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Opuntia stricta (Cacataceae)
N & C Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Eschscholzia californica (Papaveraceae)
N-Am.
Yes
Structure, abundance, succession; Other changes
Recruitment; Facilitate invasion
Adiantum raddianum (Adianthaceae)
C & S-Am.
No
Structure, abundance, succession
Competition; Recruitment.
Oxalis pes-caprae (Oxalidaceae)
(EPPO List of IAP)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Erigeron karvinskianus (Asteraceae)
C-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Spartium junceum (Fabaceae)
S & W Eur.
Yes*
Structure, abundance, succession; Other changes
Competition; Recruitment.
Pennisetum setaceum (Poaceae) (EPPO Alert List)
NE Afr.
Yes
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Paraserianthes lophantha (Fabaceae)
Aus.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion



Invasive alien plants in the top 26-75:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Conyza canadensis (Asteraceae)
N-Am.
Yes
Structure, abundance, succession
Competition; Recruitment.
Conyza bonariensis (Asteraceae)
C & S Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Lantana camara (Verbenaceae)
C & S Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Aptenia cordifolia (Aizoaceae)
S-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Solanum mauritianum (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Chasmanthe aethiopica (Iridaceae)
S-Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Tetragonia tetragonoides (Aizoaceae)
Asia, Aus., S-Am.
Yes
Structure, abundance, succession
Competition; Recruitment.
Cyathea cooperi (Cyatheaceae)
NW Aus.
No
Structure, abundance, succession; Other changes
Competition; Recruitment.
Symphyotrichum subulatum (Asteraceae)
N, C & S Am.
No
Structure, abundance, succession
Competition; Recruitment.
Ipomoea indica (Convolvulaceae)
Pantrop.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Tradescantia fluminensis (Commelinaceae)
Brasil
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Drosanthemum floribundum (Aizoaceae)
S-Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Stenotaphrum secundatum (Poaceae)
W Af., Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Ageratina riparia (Asteraceae)
Mexico
No
Structure, abundance, succession
Competition; Recruitment.
Acacia melanoxylon (Fabaceae)
Aus.
Yes
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Doodia caudata (Blechnaceae)
Aus.
No
Structure, abundance, succession
Competition; Recruitment.
Nassella neesiana (Poaceae)
S-Am.
Yes (only ES)
Structure, abundance, succession
Competition; Recruitment.
Colocasia esculenta (Araceae)
Malaysia
No
Structure, abundance, succession; Other changes
Competition; Recruitment.
Eucalyptus globulus (Myrtaceae)
Aus.
Yes
Geomorphology; Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment.
Anredera cordifolia (Basellaceae)
S-Am.
Yes
Structure, abundance, succession
Competition; Facilitate invasion
Phytolacca americana (Phytolaccaceae)
N-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Adiantum hispidulum (Adianthaceae)
SW Af.
No
Structure, abundance, succession
Competition; Recruitment.
Leycesteria formosa (Caprifoliaceae)
India, SW China
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment.
Cardiospermum grandiflorum (Sapindaceae)
Am., W India, Af.
Yes (only IT)
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Ricinus communis (Euphorbiaceae)
Af.
Yes
Structure, abundance, succession
Competition; Recruitment.
Ailanthus altissima (Simaroubaceae)
China
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion; Allelopathy
Bidens pilosa (Asteraceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Centranthus ruber (Valerianaceae)
Medit.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion
Tropaeolum majus (Tropaeolaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Pelargonium inquinans (Geraniaceae)
S-Af.
Yes (only FR)
Structure, abundance, succession
Competition; Recruitment
Opuntia tuna (Cactaceae)
Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Gunnera tinctoria (Gunneraceae)
WS Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Phormium tenax (Hemerocallidaceae)
NZ
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Egeria densa (Hydrocharitaceae) (EPPO List of IAP)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Gomphocarpus fruticosus (Asclepiadaceae)
Af.
Yes
Structure, abundance, succession
Competition; Recruitment
Cytisus striatus (Fabaceae)
Iberia, N-Af.
Yes
Fire regime; Structure, abundance, succession
Competition; Recruitment
Nicotiana paniculata (Solanaceae)
Am.
No
Structure, abundance, succession
Competition
Cotula australis (Astercaeae)
Aus, NZ
Yes
Structure, abundance, succession
Competition
Crassula multicava (Crassulaceae)
S-Af.
Yes (only ES)
Structure, abundance, succession
Competition
Deparia petersenii (Dryopteridaceae)
Asia
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Araujia sericifera (Asclepiadaceae) (EPPO Alert List)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition



Invasive alien plants in the top 76-100:

Species
Origin
EPPO
Impacts on habitats
Impacts on species
Cirsium vulgare (Asteraceae)
Eurasia, N-Af.
Yes*
Structure, abundance, succession
Competition; Recruitment
Solanum bonariense (Solanaceae)
S-Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Crassula tillaea (Crassulaceae)
S-Af.
Yes
Structure, abundance, succession
Recruitment
Acacia saligna (Fabaceae)
Aus
Yes
Structure, abundance, succession; Other changes
Competition; Facilitate invasion
Solanum lycopersicum var. lycopersicum (Solanaceae)
Am.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Nephrolepis cordifolia (Lomariopsidaceae)
Pantrop, Himal., Aus
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Pennisetum clandestinum (Poaceae)
W-Af.
Yes
Structure, abundance, succession; Other changes
Competition; Recruitment
Hedychium coronarium (Zingiberaceae)
SE Asia
No
Structure, abundance, succession; Other changes
Competition; Recruitment
Passiflora tripartita (Passifloraceae)
S-Am.
No
Structure, abundance, succession
Competition; Recruitment
Paspalum distichum (Poaceae)
Am.
Yes
Structure, abundance, succession
Competition; Recruitment; Facilitate invasion
Coronopus didymus (Brassicaceae)
S-Am.
Yes
Structure, abundance, succession
Competition
Conyza floribunda (Asteraceae)
S-Am.
Yes
Structure, abundance, succession
Competition; Recruitment
Pinus pinaster (Pinaceae)
S-Eur.
Yes*
Structure, abundance, succession
Competition; Recruitment
Soleirolia soleirolii (Urticaceae)
Corse, Sardinia, Baleares
Yes
Structure, abundance, succession
Competition; Recruitment
Agapanthus praecox (Agapanthaceae)
S-Af.
Yes (only UK)
Structure, abundance, succession
Competition; Recruitment
Duchesnea indica (Rosaceae)
Asia
Yes
Structure, abundance, succession
Recruitment
Crocosmia x crocosmiflora (Iridaceae)
Hybrid
Yes
Structure, abundance, succession
Competition; Recruitment
Aloe vera (Aloaceae)
NE Af.
Yes
Structure, abundance, succession
Competition; Recruitment
Leptospermum scoparium (Myrtaceae)
Aus, NZ
Yes (only UK)
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment
Ulex minor (Fabaceae)
W Eur.
Yes, ind
Fire regime; Structure, abundance, succession; Other changes
Competition; Recruitment; Facilitate invasion
Wigandia urens (Hydrophyllaceae)
C & S Am.
Yes
Structure, abundance, succession
Competition; Recruitment

________
*: the species in indigenous at least in part of the EPPO region.

Sources

Delivering Alien Invasive Species Inventories for Europe (DAISIE). http://www.europe-aliens.org/
Silva L, Ojeda Land E &  Rodríguez Luengo JL (eds.) (2008) Invasive Terrestrial Flora & Fauna of Macaronesia. TOP 100 in Azores, Madeira and Canaries. ARENA, Ponta Delgada, 546 pp. http://www.uac.pt/~lsilva/Flora_e_Fauna.pdf