Non-native species (NNS) are those that have been introduced, either intentionally or unintentionally, outside of their native range. A small proportion of non-native species go on to cause negative impacts on the environment, economy or human health – these are known as invasive non-native species (INNS).

INNS are recognised as one of the biggest threats to biodiversity worldwide. invasive non-native plants can block footpaths, and Japanese knotweed can damage concrete, threatening infrastructure. Giant hogweed can cause harm to human health.

Noxious/Injurious Weeds such as Thistles and Ragwort

Some native plants may also require control:

  • In Northern Ireland, noxious weeds are native species, which cause problems for farming. They are harmful to livestock and must not be allowed to spread to agricultural land.
  • In Scotland, injurious weeds are those native species that you may be required to control if they are spreading and causing a nuisance.

This guide describes your legal obligations regarding non-native species and invasive species; how to identify and control invasive species, using methods such as spraying, digging up, cutting and burning; and how to remove and dispose of them.

Useful Links

Invasive Species Northern Ireland

NatureScot - non native species

Additional Resources


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