This is an overview of the definitions use regarding invasiveness in the countries participating in NOBANIS.



The Belgian Forum on Invasive Species has adopted a list system to identify exotic species that make a threat for native biodiversity.
Alert list (A0-B0) includes species that are not yet established in Belgium which cause a moderate to a high impact on the environment in the neighbouring countries.
Black list (A1-A3) includes species with a confirmed high impact on the environment;
Grey or watch list (B1-B3) gathers species with a suspected or moderate impact on the environment.



Black list includes species that must be considered as significant invasive species in Denmark. These are both species, which are now widespread in Denmark, and species that occur only very rarely. Similarly, the black list includes both species where eradication is impossible, and species that can be combated with a limited effort.

Grey list includes species that do not yet appear invasive in Denmark, but have the potential to become invasive. This could be introduced species in countries close to Denmark, which has showed a large reproducing and / or spreading potential and which also has been shown to have significant negative consequences for biodiversity. Grey list also includes species that already exist in Denmark and that exhibit invasive characteristics and which therefore must be monitored.  



Black list includes:  
  • Alien plant species that have been introduced and are established in nature, eradication impossible
  • Extremely dangerous plants, strong generative and vegetative reproduction
  • Plants with high potentiality to naturalize
  • Dangerous invasive plants with limited dispersal (usually use only vegetative propagation)  

Germany and Austria

Black List is separated into three sub-lists: (1) Black List–warning list if the alien species is not yet present in the reference area, (2) Black List–action list if the alien species occurs only in a few localities and eradication measures are available, and (3) Black List–management list if the alien species occurs in a large area and eradication measures are hardly feasible.

The Grey List is further divided into two sub-lists (”operation”, ”observation”), based on the level of certainty of the assessment.  



Invasive 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.  


An invasive species is a species which is not native to the particular area, cause damage to native species and/or to native habitats or cause economic or environmental damage and/or cause damage to human health.

(adopted from the Latvian Plant Protection Law).  



Legally forbidden species for trade and/or possession:

Species that are mentioned in a code of conduct for aquatic alien plants. The partners declare that some species will no longer be traded, or will only be traded with additional information on the save use of these plants.

Species for which our minister announced a legal ban on trade and/or possession (not yet effective):

Species for which we try to agree on a code of conduct with the bird feed industry (not yet effective):  



High, medium and low risk species.  


Alien species whose introduction may threaten native species or habitats.