We review the extensive record of plant fossils before, at, and after the Cretaceous-Paleogene event horizons, recognizing that key differences between plants and other organisms have important implications for understanding the patterns of environmental change associated with the Cretaceous-Paleogene event. Examples are given of the breadth of prior environmental conditions and ecosystem states to place Cretaceous-Paleogene events in context. Floral change data across the Cretaceous-Paleogene are reviewed with new data from North America and New Zealand. Latest Cretaceous global terrestrial ecology was fire prone and likely to have been adapted to fire. Environmental stress was exacerbated by frequent climate variations,...