Willems, F. M., J. F. Scheepens, and O. Bossdorf. 2022. Forest wildflowers bloom earlier as Europe warms: lessons from herbaria and spatial modelling. New Phytologist 235: 52–65. https://doi.org/10.1111/nph.18124
Today plants often flower earlier due to climate warming. Herbarium specimens are excellent witnesses of such long‐term changes. However, the magnitude of phenological shifts may vary geographically, and the data are often clustered. Therefore, large‐scale analyses of herbarium data are prone to pseudoreplication and geographical biases.We studied over 6000 herbarium specimens of 20 spring‐flowering forest understory herbs from Europe to understand how their phenology had changed during the last century. We estimated phenology trends with or without taking spatial autocorrelation into account.On average plants now flowered over 6 d earlier than at the beginning of the last century. These changes were strongly associated with warmer spring temperatures. Flowering time advanced 3.6 d per 1°C warming. Spatial modelling showed that, in some parts of Europe, plants flowered earlier or later than expected. Without accounting for this, the estimates of phenological shifts were biased and model fits were poor.Our study indicates that forest wildflowers in Europe strongly advanced their phenology in response to climate change. However, these phenological shifts differ geographically. This shows that it is crucial to combine the analysis of herbarium data with spatial modelling when testing for long‐term phenology trends across large spatial scales.
Robert Stephen Adamson
March 02, 1885 – November 06, 1965
United Kingdom; Union of South Africa; United Kingdom of Great Britain and Ireland
Collected Poaceae and identified Juncaceae
Collected Asteraceae and identified Amaranthaceae
Collected Asteraceae and identified Asteraceae
Collected Parmeliaceae and identified Parmeliaceae
Collected Poaceae
Collected Ranunculaceae and identified Rosaceae
Eleonora Armitage
December 11, 1865 – October 24, 1961
United Kingdom of Great Britain and Ireland; United Kingdom
Collected Caryophyllaceae and identified Rubiaceae
Collected Poaceae and identified Poaceae
Collected Caryophyllaceae and identified Rosaceae
Collected Characeae and identified Cyperaceae
Collected Poaceae and identified Fabaceae
Collected Poaceae and identified Dermestidae
Collected Cyperaceae and identified Potamogetonaceae
Collected Caryophyllaceae and identified Polygalaceae
Collected Pottiaceae and identified Pottiaceae
Spencer Henry Bickham
November 15, 1840 – April 07, 1933
United Kingdom of Great Britain and Ireland
Collected Caryophyllaceae and identified Asteraceae
Collected Asteraceae and identified Fabaceae
Collected Asteraceae and identified Asteraceae
Collected Characeae and identified Ceratophyllaceae
Collected Asteraceae and identified Asteraceae
Collected Asteraceae and identified Poaceae
Collected Asteraceae and identified Asteraceae
Collected Rosaceae and identified Lamiaceae
John Patrick Micklethwait Brenan
June 19, 1917 – September 26, 1985
United Kingdom; United Kingdom of Great Britain and Ireland
Collected Fabaceae and identified Fabaceae
Collected Caryophyllaceae
Collected Asteraceae and identified Salicaceae
Collected Asteraceae and identified Hylocomiaceae
Collected Sphagnaceae and identified Poaceae
Collected Sphagnaceae and identified Neckeraceae
Beatrice Olive Corfe
January 19, 1866 – January 09, 1947
United Kingdom of Great Britain and Ireland; United Kingdom
Collected Caryophyllaceae and identified Poaceae