Monitoring Plants of Concern at Chicago Botanic garden

Daniella DeRose, Chicago Botanic Garden

Chicago Botanic Garden’s Plants of Concern (POC) program is a collaboration between citizen scientists, natural resource managers, and researchers to collect data on rare plant populations in northeastern Illinois. The primary goal is to identify best conservation practices, while creating awareness and providing education on why conservation matters. POC engages citizen scientists, collects census data on rare plant populations—including identifying invasive species, threats, and evidence of management—and provides data to land managers. Data generated by POC inform the Illinois rare species listing process and are used by land managers to understand population trends and prioritize activities. Program monitors also serve as ecological site stewards. POC has monitored 292 species and 2453 populations, trained 953 volunteers, and worked with 135 landowners as of December 2018. POC trains its citizen scientists to collect standardized data. Partners include volunteer groups, government agencies, private landowners, and researchers.

POC is learning how management impacts rare species. Hill’s thistle, Cirsium hillii, is a habitat specialist threatened by habitat loss and lack of management. Although monitoring and management data suggested that burning and brush removal increase population size, in-depth study revealed a discrepancy between census size and effective population size. POC founder Susanne Masi led level 2 monitoring efforts looking at demography of C. hillii. CBG scientist Jeremie Fant & MS students Abigail White and Nora Gavin-Smyth found that most populations are highly clonal. Self-incompatibility, low flowering rates, and lack of compatible mates lead to low/no seed set, but genetic augmentation (introduced pollen) is able to reduce mate limitation. Based on these results, POC modified its monitoring protocol for C. hillii, introducing a minimum size for identifying individuals. CBG scientist Jacob Zeldin developed new micropropagation techniques that allow for the rapid and controlled cloning of individual C. hillii genotypes year-round with minimal space and materials. Land managers are now interested in using genetic augmentation for this species, sharing genetic material between sites.