ENVIRONMENTALLY PROBLEMATIC PLANTS - INFO
The plants listed in this category are all becoming, or have already become, an environmental problem, usually by out-competing neighbouring plants, or by spreading prolifically.
It is now illegal to plant some of the plants in this category (Japanese Knotweed [not yet linked to]) and Giant Hogweed are the only two currently in this catagory, but more are probably to follow).
Whilst with some others you have a legal responsibility to dig up and eliminate any out-breaks on your land (this applies especially to Ragwort [not yet linked to]).
Other plants may be problematic for reasons other than being invasive, for instance:
Common Ragwort [not yet linked to] is poisonous to livestock.
Bracken Spores can initiate cancer if breathed in.
Other plants may be non-native to this country and present hazards to our native wild-life which have not gained any possible natural immunity from its effects (immunity is mainly obtained through natural selection - the poison killing those not immune to its effects leaving only those that are immune [if any!]).