Background
This twig experiment allows citizen scientists to study the influence of climate change on bud burst dates. The amount of warming (= forcing) that buds of woody species need to develop in spring is determined in relation to cold winter temperatures (= chilling) that are needed to break winter rest. This species-specific relationship is important to know since warming under climate change may further advance bud burst dates due to the faster achieved forcing or could even delay bud break when chilling in warmer winters is not sufficient.
