XVI International Botanical Congess

The oldest phenological observations in the U.K. date from 1736. We are currently archiving as many historic data as we can detect and there are possibilities of locating data older than these. Between 1875 and 1947 a national network existed to co-ordinate phenological observations. In the post-war period, observations have continued through the efforts of individuals and unrelated monitoring schemes. Such data enable us to examine how species have responded to temperature in the past and, via cautious extrapolation, how they may respond in the future. This talk employs examples from a variety of sources, but focusses on the Spring to Autumn flowering records from the national scheme to demonstrate the response of flowering events to temperature fluctuations.