Historical floras reflect broad shifts in flowering phenology in response to a warming climate

Organisms across the globe are experiencing shifts in phenological events as a result of ongoing climate change. Recently, variety novel methods have been applied order to fill gaps data set, which records often patchy temporal, spatial, and/or taxonomic resolution. Here, I tested whether changes flowering phenology could be detected through months stated 11 guides Swedish flora published over period 220 yr (1798-2018), focussing on 241 plant species (approximately 8% flora), and accounting for large increase herbarium that occurred same period. Despite coarse, monthly scale times reported, historical floras wildflower may hold potential temporal set. However, factors other than also influence any apparent time. was found start earlier (0.49 d/decade), end later (0.71 carry longer (1.19 with length associated increases regional temperature anomaly during 20th century (0.11 months/degrees C). First occurring 71% (14% showing significant negative trend), 68% ceased (20%), 80% flowered (29%). Detected appeared related species' seasonality. Later-flowering were flower longer, while increasing temperatures drive stronger responses both onset early-flowering cessation later-flowering species. Although issues exist regarding largely unknown ways by authors determined coarseness data, useful resource change research, identify compare broad climatic region's entire long time periods, well filling an otherwise