Research
Brian Charles of the Illinois Natural History Survey, through 2022 funding from the IL Department of Natural Resources, updated the S-Ranks (state conservation status ranks) for rare and listed plant species in Illinois. Brian updated S-Ranks for 330 state listed species and other species of concern. Most of the ranks had not been updated since 1987. NatureServe's conservation status ranking provides a standardized tool for assessing the vulnerability of plant species to extinction based on rarity, trends, and threats. The rank calculator produces ranks from critically imperiled (S1) to secure (5). Brian said that "Plants of Concern data has vastly assisted with ranks, as it contains an exceptional amount of detail."
Charles, B. et al. Illinois Plant S-Rank Project. Technical Report INHS 2024 (13). Prepared for IDNR Division of Natural Heritage. Issued on 6/30/2024. https://hdl.handle.net/2142/123977
Jeremie Fant is a molecular ecologist at the Chicago Botanic Garden who is interested in the genetic diversity of rare species. Even though people may think of rare plants as a collective group of species in need of conservation, every rare plant has very different reasons for its rarity. While Dr. Fant’s work focuses on genetic data, he believes that field data is also an invaluable component of his research, and that understanding the biology and ecology of rare species helps inform the direct conservation applications of genetic analyses. Jeremie has worked with Plants of Concern on a number of species including Cirsium hillii, Asclepias lanuginosa, Castilleja sessiliflora, and Ammophila breviligulata.
Kim, E.S., D.N. Zaya, J.B. Fant and M.V. Ashley (2015) Genetic factors accelerate demographic decline in rare Asclepias species. Conservation Genetics 16(2) pp. 359-369.
Fant, J.B., R.M.Holmstrom, E. Sirkin, J.R. Etterson, and S. Masi (2008) Genetic structure of threatened native populations and propagules used for restoration, in a clonal species, Ammophila breviligulata (American beachgrass). Restoration Ecology 16 (4) pp. 594-603
Fant, J.B., Susanne Masi, J.M. Keller, and R. Mann (2007) Investigating the reproductive health of Hill’s thistle (Cirsium hillii) populations in the Chicago region. Chicago Wilderness Journal 5(1).
Amy Iler is a Conservation Scientist at the Chicago Botanic Garden who studies the effects of anthropogenic change—especially climate change and biodiversity loss—on plants, pollination, and pollinators. She is interested in both rare and common plants and is fascinated by the population biology of rare plants. Dr. Iler is a field biologist and highly values the work of community scientists in all sorts of monitoring programs, but especially Plants of Concern. Dr. Iler has worked with postdocs, graduate students, and interns on analyzing Plants of Concern data for reports to stakeholders and for scientific publications.
Joshua Scholl is a former postdoctoral researcher in the Amy Iler Lab at the Chicago Botanic Garden and Northwestern University. During his postdoc, Josh used the Plants of Concern dataset to conduct rare plant population viability assessments and study the effectiveness of management strategies to conserve rare plant populations. Out of 73 populations of rare species, Josh and colleagues found that only 33 populations had probabilities of extinction >20%. His research also highlighted the importance of the concept of negative density dependence for rare species persistence, meaning that small populations can recover as their populations become less dense.
Joshua P. Scholl et al. 2022. The importance of negative density dependence for rare species persistence. Biological Conservation. https://doi.org/10.1016/j.biocon.2022.109729
While Emily was a visiting scientist at the Chicago Botanic Garden, she investigated reproductive and phenological traits of northern starflower, Trientalis borealis, spanning a latitudinal gradient from northern Illinois to northern Minnesota. She found that Illinois populations are small and isolated from each other compared to more northern populations and that individual plants are shorter and produce fewer flowers, on average. She also found that starflower demonstrates phenological responsiveness to temperature and flowers earlier when spring (March-May) mean temperatures are warmer, and documented lower flowering rates and lower fecundity in Illinois populations than in populations in northern Wisconsin and Minnesota. Her results highlight how populations of starflower are shifting in response to changing climate.
Emily M. Dangremond et al. 2022. Phenological responsiveness and fecundity decline near the southern range limit of Trientalis borealis (Primulaceae). Plant Ecology. https://link.springer.com/article/10.1007/s11258-021-01190-w
Climate Change and Starflower in the Midwest. https://illinoisplants.org/climate-change-and-starflower-in-the-midwest/
Rafael Urbina-Casanova is a PhD student with Jeremie Fant interested in the conservation of endangered plant species. He studies the influence of genetic factors on the extirpation of small plant populations, and also studies how augmenting genetic diversity and/or decreasing inbreeding can help recover rare species and improve their conservation outcomes. Rafael is also interested in restoration ecology and understanding how restoration practices could include rare species, broadening the conservation outcomes of restoration projects. Some of the Plants of Concern species that Rafael has worked with are Hill's thistle (Cirsium hillii), dwarf bush honeysuckle (Diervilla lonicera), northern starflower (Trientalis borealis), dwarf red blackberry (Rubus pubescens), and lakeside daisy (Tetraneuris herbacea).
Alexandra (Ali) Touloupas is a former research assistant for Plants of Concern and a Master's student in the Plant Biology and Conservation program at the Chicago Botanic Garden and Northwestern University. She is interested in rare plant conservation and the impacts of climate change on bog and fen species. Ali's research involves monitoring populations of two Illinois-endangered Plants of Concern species, downy willowherb (Epilobium strictum) and white beakrush (Rhynchospora alba), and using habitat data to model rare plant distributions, to ultimately inform how species and their habitats are responding to climate change.
Ingrid Felsl is a former Plants of Concern research assistant and current Master's student at Southern Illinois University-Carbondale studying the Illinois-threatened buffalo clover, Trifolium reflexum. Buffalo clover was once common along heavily trampled bison trails. Today, it is threatened in Illinois and populations occur at sites with varying types of disturbances. Ingrid is assessing the environmental and demographic differences among these populations and is interested in determining how we can conserve and create more habitat for buffalo clover. We look forward to sharing the results of Ingrid's research.
Tiany Hernandez is a Master's student in Becky Barak's Lab at the Chicago Botanic Garden and Northwestern University studying lesser purple fringed orchid, Platanthera psycodes. The lesser purple fringed orchid is a small and charismatic flowering plant that is endangered in Illinois. There is little research on this purple orchid, and in order to conserve and restore this plant and its habitats, we must first understand how they grow. Tiany is testing symbiotic orchid-fungal germination and researching early life stage development, and has sampled fungi and seeds from four known populations in Lake County, Illinois. Tiany hopes to determine optimum conditions for growing the lesser purple fringed orchid and that their research can inspire further research of these beautiful plants along with their native habitats.
For her Master's thesis, Nora asssessed mate location and genetic augmentation of two Asteraceae species that are monitored by Plants of Concern (forked aster, Eurybia furcata, and Hill's thistle, Cirsium hillii). These two species occur in woodland and prairie fragments, and both species are self-incompatible and reproduce clonally. Nora's results indicated that introducing pollen from outside populations can effectively relieve mate limitation and increase seed set in forked aster and Hill's thistle. Commonly referred to as genetic augmentation or genetic rescue, the long-term effects of this management practice are seldom measured.
Reducing Mate Limitation in the Forked Aster (Eurybia furcata): A Case Study of Genetic Augmentation. https://saveplants.org/video/reducing-mate-limitation-in-the-forked-aster-eurybia-furcata-a-case-study-of-genetic-augmentation/
Nora Gavin-Smyth et al. 2021. Genetic rescue reduces mate limitation in a threatened, clonal, and self-incompatible plant species. Restoration Ecology. https://onlinelibrary.wiley.com/doi/10.1111/rec.13458
Logan Novak is a former research assistant for Plants of Concern and former Master's student in the Plant Biology and Conservation program at the Chicago Botanic Garden and Northwestern University. While working as a research assistant, Logan and colleagues used long-term Plants of Concern monitoring and management data to assess the impacts of prescribed burning on populations of Plants of Concern species. They compared burn effects across individual rare species, across different habitat types, and with previous findings of burn response. They found that most species generally did not have strong positive or negative responses to prescribed burning. Short- and long-term species responses to burning varied.
Logan Novak et al. 2022. Prescribed burning has limited effects on the population dynamics of rare plants. Conservation Science and Practice. (Open Access) https://doi.org/10.1111/csp2.12792
Andrew Davies is broadly interested in rare plant conservation and understanding how threatened and endangered species can persist in response to anthropogenic disturbances. Andrew is using population genetics as a tool to better understand processes that contribute to small rare plant populations that are declining. He is also interested in vegetation mapping, habitat suitability modelling, and ecological restoration, particularly for rare species. Andrew is applying these methods to study the Illinois-threatened and Plants of Concern species kittentails, Synthyris bullii.
Faith Hudgens Harvey is a former Master’s student in David Gibson’s Lab in the Plant Biology program at Southern Illinois University who studied the heart-leaved plantain, Plantago cordata. Heart-leaved plantain was once common in low plant diversity, clear-running streams from Ontario, Canada to Florida but is now endangered in several states including Illinois. Following surveys of several southern Illinois populations, Faith’s research showed that growth and reproductive success of plants in extant populations were restricted to shallow, high-quality streams. Insect and deer herbivory was also a threat to reproductive success. Overall, Faith’s work reinforces the need to maintain and restore stream quality to allow persistence of populations of rare aquatic species.
Faith V. Hudgens. 2021. An assessment of stream quality in relation to population health of Plantago cordata. M.S. Thesis, Southern Illinois University Carbondale. https://opensiuc.lib.siu.edu/pb_theses/
Ben is a former Master's student with Jeremie Fant who studied the potential effects of climate change on the restoration of Pitcher's thistle, Cirsium pitcheri, in Illinois. He screened possible donor populations to determine their response to predicted climate change scenarios in order to select robust donor options. He compared seedling establishment at 2007, 2030 and 2095 projected conditions.
Benjamin M. Staehlin et al. 2015. Climate Change Impacts on Seedling Establishment for a Threatened Endemic Thistle, Cirsium pitcheri. The American Midland Naturalist. https://www.jstor.org/stable/43822782
Erin is a former Master's student with Jeremie Fant who assessed the management of the Illinois-endangered Butler's quillwort, Isoetes bulteri. Erin worked with researchers Dan Larkin and Jeremie Fant, and Plants of Concern founder and former manager Susanne Masi, to explore how management practices impacted Butler's quillwort population growth. This species inhabits sparsely vegetated moist depressions in dolomite prairies that become ephemeral wetlands in the spring. Erin used genetic tools to assess the status of five populations in Illinois and made management recommendations to encourage population growth of Butler's quillwort in Illinois.
Erin Vander Stelt et al. 2017. Assessing habitat requirements and genetic status of a rare ephemeral wetland plant species, Isoëtes butleri Engelm. Aquatic Botany. https://doi.org/10.1016/j.aquabot.2017.01.002
Lauren Lazzaro is a former doctoral student in David Gibson’s lab at Southern Illinois University Carbondale. For her research, Lauren compared the population dynamics of the state endangered bloodleaf Irisine rhizomatosa at a Plants of Concern monitoring site with other invasive weeds in the same plant family, the Amaranthaceae. A competition experiment and an integral projection model showed that bloodleaf was a poor competitor compared with the widespread weeds with a negative population growth rate due to high mortality of potentially reproductive adults. Conservation of bloodleaf depends on protection from anthropogenic disturbance.
Lauren Schwartz et al., 2016. Using integral projection models to compare population dynamics of four closely related species. Population Ecology 58: 285-292. https://doi.org/10.1007/s10144-016-0537-2
Lauren Schwartz et al., 2016. Do plant traits predict the competitive abilities of closely related species? AoB Plants 8: plv147; doi:10.1093/aobpla/plv147.
Katie is former PhD student with Jeremie Fant whose doctorate research assessed geographic variation in floral traits, and focused on how floral traits may highlight differences in local pollinators, who in turn shape gene flow and genetic structure among populations. Katie studied these factors and the population genetics and phenotypic divergence in the paintbrushes (genus Castilleja). Downy paintbrush, Castilleja sessiliflora, is a Plants of Concern species that shows dramatic variation in floral color and morphology across its range due to its pollination by hawkmoths. Katie included monitored Plants of Concern populations found in northeastern Illinois in her analyses.
Katherine E. Wenzell et al. 2021. Incomplete reproductive isolation and low genetic differentiation despite floral divergence across varying geographic scales in Castilleja. American Journal of Botany. https://doi.org/10.1002/ajb2.1700
Katherine E. Wenzell et al. 2023. Range-wide floral trait variation reflects shifts in pollinator assemblages, consistent with pollinator-mediated divergence despite generalized visitation. Oikos. https://doi.org/10.1111/oik.09708
Abby White is a former Master's student who studied vulnerable plant taxa that are rarely included in seed mixes for restorations. Her research specifically focused on species that are currently "falling through the cracks" due to limited seed availability. Her focal species, Hill’s thistle (Cirsium hillii), is a native thistle endemic to the Great Lakes region. She assessed the genetic diversity within and among populations to determine how genetically isolated these populations are regionally. Abby's landscape genetic study helped identify ways that restoration practitioners and conservationists could improve reproductive success through increasing seed set, thereby increasing seed availability for inclusion in restoration seed mixes in the future.
Abigail White et al. 2018. Restoring species diversity: assessing capacity in the U.S. native plant industry. Restoration Ecology. https://doi.org/10.1111/rec.12705
Eun Sun is a former PhD student in Mary Ashley’s Lab at the University of Illinois-Chicago. Eun Sun was interested in genetics of rare species and worked with Jeremie Fant to study the Illinois-endangered woolly milkweed, Asclepias lanuginosa, and little green milkweed, Asclepias viridiflora. She conducted population viability analyses on remnant populations of the two milkweed species and published her results in the journal Conservation Genetics.
Eun Sun Kim et al. 2015. Genetic factors accelerate demographic decline in rare Asclepias species. Conservation Genetics. https://link.springer.com/article/10.1007/s10592-014-0663-3
Susanne Masi co-founded the Plants of Concern program in 2001 and worked as the Program Manager until her retirement in 2013. Her vision and leadership helped successfully establish many of the lasting regional partnerships that sustain the Plants of Concern program. Susanne has led and contributed to many plant conservation research projects, and she has authored, co-authored, and delivered numerous publications and presentations on community science and the conservation of rare species. Her publications include the book, The Sunflower Family of the Upper Midwest, co-authored with Thomas Antonio, and a chapter titled “Retaining Citizen Scientists,” coauthored with Rachel Goad and Pati Vitt, which appears in the Handbook of Citizen Science in Ecology and Conservation. Susanne served for 12 years on the Illinois Endangered Species Protection Board and is a current member of the IL Endangered Species Technical Advisory Committee established to review the Endangered and Threatened Species List for 2024/2025. She currently serves as the Vice President of the Illinois Native Plant Society statewide board and continues to monitor rare plants as a Plants of Concern volunteer.
Kayri Havens, Pati Vitt, & Susanne Masi. 2012. Citizen science on a local scale: the Plants of Concern program. Frontiers in Ecology and the Environment. https://doi.org/10.1890/110258
Handbook of Citizen Science in Ecology and Conservation. University of California Press. https://www.ucpress.edu/book/9780520284791/handbook-of-citizen-science-in-ecology-and-conservation
Thomas Antonio & Susanne Masi. The Sunflower Family in the Upper Midwest. Indiana Academy of Science. https://www.indianaacademyofscience.org/product/the-sunflower-family-in-the-upper-midwest/