Invasive species are organisms which have spread to new areas with humans from their original natural habitats. A small part of the new species is able to reproduce in the new nature area but may cause problems for the original inhabitants.
Finland has about 1,000 invasive species, of which 157 are considered to be harmful. The most damaging in the Kuopio region are giant hogweed and balsam, which have spread to forests, meadows and wetlands and superseded the original species. In addition to hogweed and balsam in Kuopio there are other harmful invasive species which are, among others: European red elder, lupin, small balsam, giant knotweed and false bindweed.