Our gardens, parks and urban landscapes have been greatly enriched by the introduction of plants from abroad but a small number have proved highly invasive in the UK, threatening natural habitats and native species. The control of these species is difficult and can be costly if not dealt with quickly. Non-native invasive species can:
- Change ecosystems and habitats and have non-biotic effects, such as reducing or impeding water flow leading to flooding, or changing the pH or the chemical composition of the soil.
- Out-compete native species either by habitat change or by spreading so rapidly as to crowd out slower growing species, threatening the long-term survival of species.
- Be expensive to eradicate if not tackled swiftly and effectively. It is also very costly to restore degraded habitat, if it can be done at all.