Differences in drought avoidance rather than differences in the fast versus slow growth spectrum explain distributions of two Asclepias species.

ABSTRACT: Understanding factors that determine a species' geographical range is crucial for predicting climate-induced range shifts. Two milkweed species, Asclepias syriaca and Asclepias speciosa, have overlapping ranges along a moisture gradient in North America and are primary food sources for endangered monarch caterpillars. With decreasing moisture, long-lived species often exhibit slower growth and greater drought tolerance, while many annual species exhibit faster growth strategies. Using this fast-slow framework, we assessed whether traits of these two sister species differ along a fast-slow growth continuum and could explain their distributions. We measured leaf and root functional traits in common gardens and greenhouse experiments. In key measures indicative of drought tolerance (e.g., gro

SUBMITTER: Matzner SL 

PROVIDER: S-EPMC11800957 | biostudies-literature | 2025 Jan-Feb

REPOSITORIES: biostudies-literature