What data would the BBC need to collect to find out if the time of year in which conkers ripen was changing?

The BBC would need to collect data on the specific dates when conkers ripen each year over a significant period, ideally several decades. This could include observations from various geographic locations to account for regional variations. Additionally, they should gather climate data, such as temperature and rainfall patterns, to analyze any correlations between environmental changes and ripening times. Finally, public reports or citizen science contributions could enhance the dataset by providing localized information.