This comprehensive reference work investigates the identification, classification, and ecological impact of non-native plant species established within the British Isles. Clive A. Stace, a distinguished botanist, utilizes decades of field research and taxonomic expertise to document the arrival and spread of alien flora. The text provides a systematic framework for understanding how these introduced species interact with indigenous ecosystems and the broader environment.

This volume is regarded as a definitive resource for professional botanists and serious naturalists studying the changing landscape of British flora. The text provides a dense, highly technical examination that serves as a standard reference for identifying non-native plant populations.