Management of Crassula helmsii in Belgium
In their paper, Delbart et al. (2011) explained that in Belgium, although land managers can access a lot of information on Crassula helmsii (Crassulaceae, EPPO A2 List), they may feel disarmed when attempting to limit the damage this aquatic plant may cause to freshwater habitats. In particular, there is a lack of clarity on the means of spread of the species (e.g. whether the species is spread by waterfowl or not) which thus lead to uncertainties on the methods required to prevent its propagation. Data is also missing on the exact distribution of the species in Belgium. Although Crassula helmsii can no longer be eradicated in Belgium, the authors advocate for a concerted management strategy for this species.
Sources
Delbart E, Monty A, Mahy G (2011) Gestion de Crassula helmsii en Belgique plus difficile qu’il n’y paraît ? Bulletin OEPP/EPPO Bulletin 41, 226–231. (in French, abstract in English)