It’s one day after the autumnal equinox and rather chilly here along the Rocky Mountain Front Range. The aspens in the mountains are a blaze of yellow, and the other day I saw the first leaves turning color down at this elevation. We see these yellow, orange, and red colors in the fall leaves as trees shut down in preparation for winter. The shorter daylengths cause trees to stop producing chlorophyll, so that anthocyanins (red pigments) and carotenoids (yellow and orange pigments) become visible.
Changes in leaf color are an example of a phenological change. Phenology is the study of the timing of life cycle events in plants and animals—budburst, flowering, animal migration, and other events. Farmers have long been aware of how phenological observations relate to agricultural production, but more recently the observations have found increasing use in science, particularly for tracking the effects of climate variability and change.
Phenological observations provide a great opportunity for citizen science. Citizen science projects allow anyone willing to do some observing to report their findings and contribute to scientific analysis and research. One of my goals is to share these opportunities with you, when possible, and Project Budburst is a great one. It’s simple to participate: take a look around, and if you have kids, encourage them to look with you. Watch for seeds ripening, leaf color change, leaf drop, and other phenological events documented on the website, and login and report your observations. This important citizen science project has a goal of recording 5,000 phenophase observations this fall. You can help them get there, and do some learning and sharing about science all while enjoying the spectacular fall colors!