What are Invasive Species?

Invasive Non-Native Species (INNS) are species of plant or animal that have been brought to the UK, and cause problems for our native ecosystems.

INNS may outcompete our native species for food or other resources such as shelter and territory.

A classic example of an invasive species is the North American grey squirrel, which was brought to Europe in the 1800s. Grey squirrels breed more frequently than our native red squirrels, meaning they have larger populations and outcompete them for crucial resources. In addition, grey squirrels carry squirrel pox which they are immune to, but infects the red squirrel population. Grey squirrels also damage the local ecosystem by eating away the bark on trees and weakening or even killing them.

In the UK, we have three main plant INNS that are prolific and cause damage to our local ecology.

These are Japanese Knotweed, Himalayan Balsam and Giant Hogweed – which is particularly nasty due to its phototoxic sap that can cause large and painful blisters on the skin.

Click the links below to find out how to identify these invasive and non-native plant species.

Identifying Giant Hogweed

Identifying Himalayan Balsam

Identifying Japanese Knotweed