New records of alien and invasive plants in Georgia
Within the framework of a Swiss-Georgian research project, literature sources and field surveys were compiled in order to prepare an inventory of the alien flora of Georgia. The Georgian vascular flora includes 4200 taxa, of which 460 are alien. Of these 460 alien species, 80 are cultivated, and the 380 remaining ones are either considered subspontaneous, adventive, naturalized or invasive. Alien species thus represent 8.9% of the flora of Georgia. Almost a third of all alien species recorded in Georgia have been introduced from Asia (33%). Of these, approximately 90% originate from East Asia. A high number of species are of Mediterranean origin (22%), and over the recent years, an increasing number of plant invaders of North American origin (17%) have been recorded in the western parts of Georgia. Plant invaders from Europe (13%) are mainly from Atlantic Europe.
Among the 16 species considered to be invasive in Georgia, 10 originate from Asia and 4 from North America. No European or Mediterranean species have become invasive so far, although many species of these origins are now naturalized in Georgia.
The following 16 alien plants are considered invasive in Georgia, their origin, life form and ecological group are indicated, as well as their distribution in the EPPO region according to the DAISIE database:
|
Species
|
Origin
|
Life form
|
Ecological group
|
EPPO region
|
|
Ailanthus altissima (Simaroubaceae) (EPPO List of Invasive Alien Plants)
|
E-Asia
|
Tree
|
Dry grasslands
|
Widespread
|
|
Ambrosia artemisiifolia (Asteraceae) (EPPO List of IAP)
|
N-Am.
|
Annual
|
Ruderal
|
Widespread
|
|
Clerodendrum bungei (Verbenaceae)
|
E-Asia
|
Shrub
|
Ruderal
|
/
|
|
Crassocephalum crepidioides (Asteraceae)
|
S-Am.
|
Annual
|
Ruderal
|
TR
|
|
Miscanthus sinensis (Poaceae)
|
E-Asia
|
Perennial
|
Ruderal
|
Azores (PT), IT, TR
|
|
Opuntia humifusa (Cactaceae)
|
N-Am.
|
Shrub
|
Dry grasslands
|
ES, FR, GR, IT
|
|
Opuntia phaeacantha (Cactaceae)
|
N-Am.
|
Shrub
|
Dry grasslands
|
ES
|
|
Paspalum dilatatum (Poaceae)
|
S-Am.
|
Perennial
|
Lowlands
|
ES (incl. Baleares, Canarias), FR (incl. Corse), GR, IT (incl. Sardinia), PT (incl. Azores, Madeira)
|
|
Perilla frutescens (Lamiaceae)
|
E-Asia
|
Perennial
|
Marshes and wet meadows
|
/
|
|
Pleioblastus distichus (Poaceae)
|
E-Asia
|
Perennial
|
Ruderal
|
/
|
|
Pleioblastus humilis (Poaceae)
|
E-Asia
|
Perennial
|
Ruderal
|
/
|
|
Pleioblastus pumilus (Poaceae)
|
E-Asia
|
Perennial
|
Ruderal
|
/
|
|
Rhus javanica (Anacardiaceae)
|
E-Asia
|
Tree
|
Ruderal
|
/
|
|
Robinia pseudoacacia (Fabaceae)
|
N-Am.
|
Tree
|
Forest
|
Widespread
|
|
Spiraea japonica (Rosaceae)
|
E-Asia
|
Shrub
|
Ruderal
|
BE, DE, FR, GB, IT
|
|
Vitex rotundifolia (Verbenaceae)
|
E-Asia
|
Shrub
|
Lowlands
|
/
|
Other species are not considered as invasive in Georgia, but are listed by EPPO (EPPO A2 List, EPPO List of Invasive Alien Plants, or Alert List), and should deserve further attention in Georgia:
|
Species
|
Origin
|
Life form
|
Ecological group
|
|
Akebia quinata (Lardizabalaceae) (EPPO Alert List)
|
E-Asia
|
Shrub
|
Ruderal
|
|
Amorpha fruticosa (Fabaceae) (EPPO List of IAP)
|
N-Am.
|
Shrub
|
Forest
|
|
Araujia sericifera (Asclepiadaceae) (EPPO Alert List)
|
S-Am.
|
Shrub
|
Ruderal
|
|
Baccharis halimifolia (Asteraceae) (EPPO List of IAP)
|
N-Am.
|
Shrub
|
Marshes and wet meadows
|
|
Buddleja davidii (Buddlejaceae) (EPPO List of IAP)
|
E-Asia
|
Shrub
|
Ruderal
|
|
Cyperus esculentus (Cyperaceae) (EPPO List of IAP)
|
Medit.
|
Perennial
|
Marshes and wet meadows
|
|
Egeria densa (Hydrocharitaceae) (EPPO List of IAP)
|
S-Am.
|
Aquatic plant
|
Aquatic plant
|
|
Helianthus tuberosus (Asteraceae) (EPPO List of IAP)
|
N-Am.
|
Perennial
|
Ruderal
|
|
Hydrocotyle ranunculoides (Apiaceae) (EPPO A2 List)
|
E-Asia
|
Perennial
|
Lowland
|
|
Microstegium vimineum (Poaceae) (EPPO Alert List)
|
Asia
|
Annual
|
Ruderal
|
|
Oxalis pes-caprae (Oxalidaceae) (EPPO List of IAP)
|
South Africa
|
Perennial
|
Ruderal
|
|
Polygonum perfoliatum (Polygonaceae) (EPPO A2 List)
|
E-Asia
|
Perennial
|
Ruderal
|
|
Reynoutria japonica (Polygonaceae) (EPPO List of IAP)
|
E-Asia
|
Perennial
|
Ruderal
|
|
Solidago canadensis (Asteraceae) (EPPO List of IAP)
|
N-Am.
|
Perennial
|
Ruderal
|
Some other species, even if not listed by EPPO, are considered invasive in some EPPO countries, and should also deserve attention: e.g. Acer negundo (Aceraceae), Aster novae-angliae (Asteraceae), Aster novi-belgii (Asteraceae), Conyza bonariensis (Asteraceae), Conyza canadensis (Asteraeceae), Cuscuta campestris (Cuscutaceae), Elodea canadensis (Hydrocharitaceae).
Sources
Delivering Alien Invasive Species Inventories for Europe.http://www.europe-aliens.org/speciesSearch.do
Kikodze D, Memiadze N, Kharazishvili D, Manvelidze Z, Mueller-Schaerer H (2010) The alien flora of Georgia. 36 pp.