摘要:The vascular fora of Britain and Ireland is among the most extensively studied in the world, but the current knowledge base is fragmentary, with taxonomic, ecological and genetic information scattered across diferent resources . Here we present the frst comprehensive data repository of native and alien species optimized for fast and easy online access for ecological, evolutionary and conservation analyses. The inventory is based on the most recent reference fora of Britain and Ireland, with taxon names linked to unique Kew taxon identifers and DNA barcode data . Our data resource for 3,227 species and 26 traits includes existing and unpublished genome sizes, chromosome numbers and life strategy and life-form assessments, along with existing data on functional traits, species distribution metrics, hybrid propensity, associated biomes, realized niche description, native status and geographic origin of alien species. this resource will facilitate both fundamental and applied research and enhance our understanding of the fora’s composition and temporal changes to inform conservation eforts in the face of ongoing climate change and biodiversity loss.