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The code of conduct on invasive plants


Towards a change of attitude to reduce the spread of invasive plants...


What is this code of conduct?

The code of conduct on invasive plants is a document recommending the adoption of best practices to limit introductions and spread of invasive species in parks, gardens, ponds, nurseries or along roadways, railways and riverbanks, which are the starting points of numerous invasions in natural habitats. It is a self-regulation tool based on awareness, education and voluntary adoption of preventive measures. It aims at inducing a positive change of attitude concerning the use of invasive plants. Codes of conduct can be adopted by anyone concerned by the use of ornamental plants: horticulture professionals (green sector) or gardeners.


                     code of conduct FOR HORTICULTURE PROFESSIONALS

                     code of conduct FOR GARDEN AMATEURS


The Belgian Code of conduct: a consultative approach

For the first time in Belgium, a code of conduct on invasive plants is being implemented. This code has been prepared through round table discussions and consultations, with a representative sample of green sector professionals, representatives of horticultural federations and associations, scientists involved in invasion biology and members of the AlterIAS team, gathering a total of 70 participants organized in different working groups.

The content of the code has been approved by the main horticultural federations and associations active throughout the country (Wallonia, Flanders, Brussels: see logos below).The code is actively supported by regional and federal administrations responsible for environment in Belgium (Agentshap voor Natuur en Bos, Bruxelles Environnement – Leefmilieu Brussel, Federal Public Service Public Health-Food Chain Safety and Environment – DG Environment, Service Public de Wallonie).

La Fédération Wallonne Horticole
Algemeen Verbond van Belgische Siertelers en Groenvoorzieners
L'Association pour les Espaces Verts Communaux
Vereniging Voor Openbaar Groen
La Fédération Belge des Entrepreneurs Paysagistes
L’Association Bruxelloise des Gestionnaires des Plantations /
Brusselse Vereniging voor Plantsoen Beheerders (ABGP/BVPB)
L’Association Belge des Architectes de Jardins et Paysagistes
Belgische Tuincentra Vereniging


What about codes of conduct in other countries?

Codes of conduct are recommended by the Council of Europe, the Botanic Gardens Conservation International (BGCI) and the European and Mediterranean Plant Protection Organization (EPPO). Here below a few links to some other similar initiatives:

In June 2011, a survey realized by the EPPO reported a total of 12 national initiatives involving Codes of conduct either on-going or planned (including other countries like Denmark, Estonia, Liechtenstein, Norway, Poland, Slovakia, Slovenia and Spain). This demonstrates how such approaches are actively developing all around Europe.


Complementary approaches to code of conduct

In addition to self-regulation tools like code of conduct, legal instruments are complementary approaches to prevent the introduction and spread of invasive plants. Legislation can focus on import, trade or plantation/use of invasive plants. It can be implemented at a regional, federal, European or international level. Different initiatives are in preparation or under application. At a national level, a few European countries have addressed the issue (see the Council of Europe Code of conduct – section relevant European national initiatives). Furthermore governments are also involved in communication an awareness raising activities, early warning and rapid response, eradication and control of problematic IAS (Invasive Alien Species) and in restoration of invaded areas.


European level

In preparation: there are some limited categories of IAS and pathways that are already well regulated and covered, e.g. plant pests, aquaculture but there is no unified system to control IAS. A dedicated legislative instrument on invasive alien species at European Union level is in development.


Federal level

In preparation: Royal decree that provides for a ban on the import, export, transit of IAS from the black and alert lists. The decree concerns invasive alien plants that are not yet established or not widely distributed in the country should be enforced. It includes the following species: Carpobrotus acinaciformis and C. edulis (Aizoaceae), Crassula helmsii (Crassulaceae), Egeria densa (Hydrocharitaceae), Lagarosiphon major (Hydrocharitaceae), Ludwigia grandiflora and Ludwigia peploides (Onagraceae), Myriophyllum aquaticum and M. heterophyllum (Haloragaceae).


Regional level  

Following the law about nature conservation and regional transcriptions of the Habitat directive (Natura 2000 directive), it is forbidden to introduce any alien species in the wild in each region, with some exceptions for specimens of plant species used for forestry, agriculture and sometimes horticulture. Legislative texts are available for Wallonia (décret relatif à la conservation des sites Natura 2000, de la faune et de la flore sauvages, art. 2 - section 5), Flanders (Soortenbesliut, art. 17) and Brussels (art. 14). On top of this, other regional legislations are in preparation or under application.


In Wallonia
Under applicationCirculaire wallonne (23/09/2009) concerning intentional plantations of invasive alien plants within the frame of public tender procedures.

In Flanders
Under application: To allow reducing negative impact on native biodiversity of IAS in the wild, to mitigate or to restore, the Flemish minister responsible for the Environment can take measures (articles 28, 29, 30 and 31 of the ‘Soortenbesluit’, see link above). The following actions are possible:

  • actions for increasing awareness including facilitating codes of conduct;
  • doing, letting do, or enforcing of specific management and control;
  • making agreements with local governments and/or organisations aiming at local actions;
  • limiting or prohibiting transport, trade and possession.

In preparation: A legislative action plan on four species of invasive water plants is currently in preparation. This action plan includes a sectorial agreement on a ban on trade for Hydrocotyle ranunculoides, Myriophyllum aquaticum, Ludwigia grandiflora and Ludwigia peploides.

In Brussels
In preparation: the new Ordonnance Nature, containing measures on the trade and plantation of invasive alien plants.