Identifying Threats

Much of our science program focuses on how human activities are affecting plants, through climate change, habitat fragmentation, introduction of invasive species, pollinator loss, pollution, and more. These threats to plants are unlikely to diminish in the foreseeable future and we are working to find ways to conserve plants in changing and challenging environments.

Climate Change and the Conservation of Key Plant-Soil Relationships

Tropical forests exchange more water and carbon dioxide (CO2) with the atmosphere than any other biome, and thus play a major role in global carbon cycling.  These forests are likely to experience declines in rainfall and increases in length and intensity of seasonal drought in the near future. If so, tropical forests could become a source, rather than a sink, of CO2.  Even small shifts in rainfall could reduce tree growth and increase tree mortality that, together, could alter the composition and function of tropical forests.

North Shore Ravine Restoration and Conservation

Plants of Concern

Plants of Concern and other CBG staff have been major contributors to a suite of conservation projects focused on Illinois’ north shore ravines.  POC staff have led efforts to develop a rapid assessment protocol for land managers to use in evaluating ravine plant communities, and the program is working to find additional funding to finalize the tool and use it in comprehensive ravine assessment.  In addition, long-term monitoring of rare species by Plants of Concern staff and volunteers is feeding efforts to control invasive plants along the ravines and north shore of Lake Michigan.  Starti

Phenology Projects

Red columbine

The Chicago Botanic Garden manages Budburst, a web-based, national, citizen-science program designed to engage the public in collecting data on the effects of climate change on plants and ecosystems. Scientists at the Garden and across the country use observations of plant phenology (when plants annually leaf out, bloom, fruit, and die back) to draw conclusions about how changes in climate will affect the relationships between plants and their pollinators, agricultural and horticultural practices, and invasions of weedy species.

Seed Germination and Climate Change


Seed recruitment is predicted to be one of the most at-risk stages for plant regeneration in a changing climate. Seed dormancy break, germination, and seedling establishment are critical stages in plant regeneration, with consequences for plant fitness, population persistence, and colonization of new sites. Understanding how early life stages vary–among species and at the population level–is essential to accurately predicting responses to climate change and implementing successful restorations.

Gravel Hill Biodiversity

Gravel hill prairie

Much like wetlands, gravel hill prairies represent a microcosm within the tallgrass prairie. The drier conditions support a unique plant community, including a number of important endemic and rare species. With landscape fragmentation, these habitats are becoming increasingly isolated, and many populations are declining and exhibiting reproductive failure. We propose to identify demographic, genetic, and management-related drivers of population decline, and to address identified issues through ex situ and later in situ experiments.

Rooftop Ecosystems

City Hall Greenroof

City green spaces are being recognized as important components of the urban ecosystem providing usable habitat for many organisms, including migrating species. Green roofs are just one example of an urban green space, but they are both novel and rapidly increasing in area within North America. Graduate student Kelly Ksiazek has been documenting the ecological services that green roofs provide, as well as describing the ecological services found on the green roofs. Her work has resulted in three publications to date (Ksiazek, Skogen, and Fant).

Using Plant Community Phylogenetics to Inform Restoration of Tallgrass Prairies

We are using emerging analytical tools to incorporate understanding of plant evolutionary history into studies of prairie community change, management, and restoration. We have found that phylogenetic diversity of remnant prairies—how broadly from across the "Tree of Life" their constituent species are drawn—is an effective indicator of environmental conditions, community change, and management history in remnant prairies. Restored prairies that we have analyzed to date have significantly lower phylogenetic diversity than these remnant prairies, whih serve as targets for restoration.

Long-Distance Gene Flow and Hawkmoth Pollination


Long-distance pollination has widespread implications ranging from limiting population divergence, accelerating the spread of adaptive traits, disrupting gene complexes, and maintaining species cohesion. This is particularly the case for floral traits where long-distance pollinators act as agents of selection while also constraining divergence. Since 2008, we have focused on Oenothera harringtonii, an endemic to southeastern Colorado, and in 2011, we initiated similar studies on Castilleja sessiliflora in Colorado and Illinois.

Species Distribution Modeling

In 2011, we started research in modeling the species distribution of rare plants in the western United States. The project, funded by the U.S. Bureau of Land Management, is examining the current and potential distribution of more than 500 rare plants, including many cacti species. In 2014, additional distribution models were created for most of the species being studied and staff again spent time validating the distribution models for a small portion of our rare species.