National Phenology Network tree phenology: Phenology, the timing of biological events such as bud break, plant flowering times and bird migration

Phenology is the study of recurring plant/animal phenophases. Environmental changes will likely impact phenological events at the species level and above. Most of the phenological changes are unknown at the species level and may have large impacts on natural ecosystems in the future. As part of a long term phenological experiment on forest ecosystems, since spring 2009 phenophases were observed on strategically selected forest species. This experiment is part of the National Phenology Network (USA-NPN).