Geographic Variation of Germination, Growth, and Mortality in Sugar Maple (Acer saccharum): Common Garden and Reciprocal Dispersal Experiments

• Published in: Physical geography Vol. 32; no. 1; pp. 1 - 21
• Main Authors: McCarragher, Shannon R., Goldblum, David, Rigg, Lesley S.
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis Group 01.01.2011; Taylor & Francis
• Subjects: Acer saccharum; Bgi / Prodig; Biogeography; common garden experiment; geographic variation; germination; Physical geography; Plant geography; reciprocal dispersal; Eastern United States; United States of America; Human impact; Bioclimatology; Temperature; Climatic change; Biogeography; Experimentation; Sugar maple
• DOI: 10.2747/0272-3646.32.1.1
• ISSN: 0272-3646

If current temperature trends continue and increase as predicted by general circulation models, the persistence and migration of sugar maple (Acer saccharum) at its northern limit will become crucial to its continued existence in North America. Specifically, anthropogenic warming may affect germination success and growth of sugar maple. To evaluate this potential limitation, our study addresses two questions. The first involves a growth chamber: Do temperatures at and above (1°, 7°, and 14° C) sugar maple's optimal germination temperature affect its germination? The second involves a common garden: Do sugar maple germination and subsequent growth and mortality rates show evidence of geographic variation under current climatic conditions? While sugar maple germinated successfully at 7° C in the lab, field results suggest that other environmental variables may limit its future establishment as climate changes. Germination of seeds from sugar maple's northern range limit was significantly reduced under warmer conditions, and subsequent seedling mortality rates were significantly increased when grown at a more southerly latitude. Local adaptation was evident with respect to germination, survival, and growth in the field. Ultimately, results from this study further the understanding of how predicted anthropogenic climate change may affect the regeneration of sugar maple in the future.