Considering herbivory in seed sourcing decisions for restoration materials

The success of ecological restoration relies on the sourcing of native plants that not only can successfully be grown commercially and establish at restoration sites, but also can support a broader ecological community. One of the primary ways that plants provide this support is as forage for herbivores. In the Western US, forbs have been identified as an important resource for herbivores. While much is known about a variety of native forb species and the herbivores they support, less is known about how these herbivore interactions are influenced by population-level variation in plant traits. This study utilized three species of native forbs in two common garden settings to examine the effects of source population on growth, reproduction, and herbivory. Throughout the growing season of 2020, we collected data on biomass, height, reproductive output, and survival from two different populations of each species. Half of the study plots were enclosed in mesh wire to parse out the impact of vertebrate herbivory on these metrics. We also utilized data from wildlife cameras, rodent track pads, and seed trials to establish a better understanding of the community of vertebrates present in the gardens. Despite evidence of herbivore presence in the plots and significant differences in plant traits between populations, there were no significant effects of the vertebrate exclosures on plant growth or reproduction. However, there was a significant negative effect of proximity to the garden edge on survival of Dieteria canescens. The results of this study suggest that the selection of herbivory-resistant plant materials for restoration may not require population-level specificity, at least for these species, but that commercial growers should consider garden layout when aiming to maximize propagation success