Plant performance predicted by genetic variation and environmental distance in important restoration shrub species Cercocarpus montanus

Abstract

Seed transfer guidelines are used to guide the human‐mediated movement of plant propagules from collection to recipient sites and are designed to minimize the risk of introducing maladapted genotypes. The spatial scale of adaptation, however, is unknown for most species, making it difficult to assess the potential negative impacts of seed transfer. In this study, we generated seed transfer guidelines for an ecologically important shrub, alder‐leaf mountain mahogany (Cercocarpus montanus). We plant material from 24 populations of C. montanus along a latitudinal transect from the southern Rocky Mountains of New Mexico, Colorado, and Wyoming. Seeds and seedlings were sown and planted separately in common garden experimental sites representing dissimilar environments. We measured plant germination, survival, growth, and leaf morphology for three growing seasons, and found significant variation among populations. Environmental and genetic distance were useful predictors of population performance in our common garden trials, which we use to recommend broad‐scale seed transfer guidelines to minimize risk of maladaptation to restoration sites.