Phenology models using herbarium specimens are only slightly improved by using finer-scale stages of reproduction.

Premise Of The Study: Herbarium specimens are increasingly used to study reproductive phenology. Here, we ask whether classifying reproduction into progressively finer-scale stages improves our understanding of the relationship between climate and reproductive phenology.

Methods: We evaluated herbarium specimens across eastern North America, classifying them into eight reproductive phenophases and four stages of leaf development.