Lamium galeobdolon argentatum, invasive behavior of an ornamental plant
Horticultural trade is considered the most important pathway for the introduction of non-native plant species. In Europe more than 50% of the naturalized non-native plant species have been imported for horticultural purposes. Invasive non-native plant species are considered a major threat to native biodiversity, affecting ecosystems by changing native plant diversity and species composition.
In a recent study in Switzerland, the authors compared the performance of the horticultural non-native Lamium galeobdolon subsp. argentatum (Variegated yellow archangel) escaped in forests with that of the closely-related native Lamium galeobdolon subsp. galeobdolon (L.) (Yellow archangel) found in the same habitat. The study showed that the presence of Lamium g. argentatum reduced native plant species richness, changed the species composition and altered several soil properties in suburban deciduous forests.
Results demonstrate that L. g. argentatum should be considered an invasive taxon and suggest that L. g. argentatum should be added to the Black List of Invasive Species in Switzerland as well as in other countries.
The occurrence of L. g. argentatum can often be associated with the presence of nearby garden waste dumps in forests.
Prevention of the invasion of non-native plants can be avoided by banning waste dumps and raising awareness among garden owners and the general public about the negative effects of non-native species.
The common goal to create awareness and a more ecologically informed public is pursued across Europe by several initiatives, amongst which is worth mentioning Be Plant Wise in UK and Invaplant in Spain: You may find further information visting the Citizen Science repository link and consulting the Code of conduct on botanical gardens and invasive alien species at https://easin.jrc.ec.europa.eu/easin/Documentation/Codesofconduct