What are invasive non-native plants?

Some invasive non-native plants

Control projects

Britain’s native flora and fauna comprise the species that naturally colonised the land as the ice retreated after the last ice age, some 10,000 years ago. This process of steady colonisation was subsequently brought to a halt when the land-bridge between Britain and continental Europe was severed.

Scotland’s native plants and animals have evolved together over a long period of time. During most of this period, ecosystems remained relatively stable. Populations of predators and prey were held in balance, and extinctions were rare.

This stability has been increasingly disrupted as man has altered the natural environment. These changes included the introduction of species from other areas, initially from elsewhere in Europe, but then further afield. We term these non-native species.

Over the past few thousand years, animals and plants have been transported great distances, either deliberately or inadvertently, through human migration and trade.

Many non-native species have been introduced into Britain for agriculture, amenity, timber production, aquaculture, sport fisheries and the pet trade. Other introductions have occurred accidentally as ‘stowaways’ through the global transport of goods.

Many non-native species provide considerable benefits, especially in agriculture, horticulture and forestry and will continue to be a valuable economic resource.

However, others have spread rapidly and are having a negative impact on the Scottish environment and economy.

Coille Alba is actively involved in the control of invasive plants in a number of locations in Highland. These include:

  • Glenurquhart, where we carried out a survey of riparian invasive non-native plants (INNPS) and drafted a management plan in 2007; we have implemented control there since 2008
  • the Lower Ness catchment, where we have controlled riparian INNPS since 2011
  • Corrieshalloch Gorge: survey and control of Japanese knotweed
  • Kinloch Hourn: survey and control of rhododendron
  • Isle of Mull: control of Cotoneaster, which is invading species-rich habitats below volcanic sea-cliffs...


Read more

Japanese knotweed

Read more

Giant hogweed

Read more

Skunk cabbage

Read more

Himalayan balsam

Read more

White butterbur

Read more


Read more

Rhododendron at Kinloch Hourn

A Critical Review of work undertaken to control invasive rhododendron in Scotland:

 Click here to download the report



Lower Ness & Glenurquhart INNPS

Read more


Giant hogweed control on River Wick