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 Acer rubrum herbarium specimens across eastern North America, classifying them into eight reproductive phenophases and four stages of leaf development. We fit models with different reproductive phenology categorization schemes (from detailed to broad) and compared model fits and coefficients describing temperature, elevation, and year effects. We fit similar models to leaf phenology data to compare reproductive to leafing phenology. Results Finer-scale reproductive phenophases improved model fits and provided more precise estimates of reproductive phenology. However, models with fewer reproductive phenophases led to similar qualitative conclusions, demonstrating that A. rubrum reproduces earlier in warmer locations, lower elevations, and in recent years, as well as that leafing phenology is less strongly influenced by temperature than is reproductive phenology. Discussion Our study suggests that detailed information on reproductive phenology provides a fuller understanding of potential climate change effects on flowering, fruiting, and leaf-out. However, classification schemes with fewer reproductive phenophases provided many similar insights and may be preferable in cases where resources are limited.
1.Nat Hist Museum Los Angeles Cty, La Brea Tar Pits & Museum, 5801 Wilshire Blvd, Los Angeles, CA 90036 USA 2.Boston Univ, Biol Dept, 5 Cummington Mall, Boston, MA 02215 USA 3.Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA 4.Harvard Univ, Harvard Univ Herbaria, Cambridge, MA 02138 USA 5.Univ Minnesota, Dept Biol Teaching & Learning, Minneapolis, MN 55455 USA 6.Univ Washington, Dept Biol, 24 Kincaid Hall, Seattle, WA 98195 USA
Recommended Citation:
Ellwood, Elizabeth R.,Primack, Richard B.,Willis, Charles G.,et al. Phenology models using herbarium specimens are only slightly improved by using finer-scale stages of reproduction[J]. APPLICATIONS IN PLANT SCIENCES,2019-01-01,7(3)