Phenology with John O’Keefe – Thursday, April 18th @ 7 pm: John, a retired forest ecologist at the Fisher Museum/Harvard Forest, will introduce the science of phenology, the study of biological events that are controlled by climate, and discuss his now 35-year-long study of the timing of spring leaf emergence and autumn leaf senescence and drop on a group of about 50 trees at Harvard Forest. The results may surprise you!