Illinois is home to approximately 2,107 native plant species of which about 16% are listed as threatened or endangered (T & E). In addition to the common threats associated with the decline of these species, climate change is a rapidly emerging threat. Climate predictions for Illinois have estimated that summer temperatures will resemble present-day summers in Texas by mid- to latecentury, while precipitation patterns are less predictable. Using NatureServe’s Climate Change Vulnerability Index (CCVI) tool we evaluated the climate change vulnerability for all 331 of Illinois T & E plant species. Overall, we found that over 80% are vulnerable to climate change. Barriers to migration are a leading factor associated with vulnerability in Illinois, where 97% of listed species are affected by anthropogenic barriers and 24% are affected by natural barriers. The sensitivity of species to changes in temperature, precipitation, and hydrology are also associated with vulnerability. The CCVI score was associated with most of the dozen or so other factors incorporated in the tool, though to a lesser degree. This study provides insights into the most vulnerable plant species in Illinois and provides much needed information to land managers, policy makers, and researchers. By highlighting which T & E species are most vulnerable to climate change, and what factors are most responsible for their vulnerability, this work will aid in prioritizing limited resources and developing adaptation strategies for them.
Articles from our Current Issue
ABSTRACT: The biodiversity of freshwater springs in the Arkansas Ozarks is poorly described and has received relatively little attention from researchers. Information on the biodiversity of springs is crucial for their management and conservation. This study describes the aquatic and semi-aquatic plant communities and key habitat features of several springs located at Buffalo National River, Arkansas. We report 58 taxa from among all springs, including eight genera of algae, one species of horsetail, three marchantiophytes, and one bryophyte. Among angiosperms, we found 21 species of monocots and 24 species of eudicots. Six non-native species occur among the springs and none are considered to be invasive. Data show that impounded springs tend to have higher plant diversity than springs with primarily lotic geomorphologies. Cluster analysis showed that the springs with a prominent lentic structure were most similar to each other with respect to shared taxa, while the springs with well defined, long spring-runs and no functional impoundments shared the most taxa. Geographic proximity in the watershed does not appear to play a substantial role in similarity of plant populations, indicating other factors are involved. An NMDS analysis of habitat and water chemistry data corroborated the cluster analysis and showed that habit structure plays a key role in plant community composition. Springs at Buffalo National River occurring within the Boston Mountains and Springfield Plateau appear to have lower taxonomic diversity compared to the larger springs occurring on the adjacent Salem Plateau, which is likely because of their low magnesium concentrations.
JoVonn G. Hill and John A. Barone, eds. 2018. Southeastern Grasslands: Biodiversity, Ecology, and Management. Published by The University of Alabama Press, Tuscaloosa, 344 p. Hardbound, $54.95. ISBN 978-0-8173-1988-5 Southeastern Grasslands: Biodiversity, Ecology and Management is a collection of 20 research and review articles that focus on the floristics, conservation, and ecological history of grassland prairies in the southeastern United States. The volume “was inspired by the” 2012 Southeast Prairie Symposium and is a varied tribute to a unique and disappearing biome that has been reduced to less than 10% of its original range. Human encroachment, climate change, and invasive species have virtually eradicated the open grasslands that once dotted the USA from east Texas to the Atlantic Coast. The book was written “with a broad audience in mind,” however, each chapter is written in a research format with Introduction, Methods, Results, and Discussion sections suggesting the more likely audience comprises academic and conservation scientists. Because each chapter was inspired by a 15 minute research talk, chapters are concise with discussion sections closer in length to an abstract. And although this book is not directly marketed as a textbook, the hardcover has the weight and dimensions of a standard textbook at 9 × 12 inches and 5.4 pounds, so it is a rather large book to lug around and after carrying the book between my office and home more than a few times the binding started to fray and a few pages came loose. The text is rather large with
Purple loosestrife (Lythrum salicaria) is documented for the first time for Louisiana in Plaquemines Parish, extending its range southward about 310 km. Three species of Lythrum are now known for Louisiana, and four species have been recorded for the central Gulf and lower Mississippi valley regions. A key to species and regional distributional data are provided for L. salicaria.
Thompson Pond, a bog lake in Pine Plains, New York, has flora indicative of both ombrotrophic and minerotrophic conditions. Distinct community types within this wetland system include a peripheral moat, hummock swamp, floating vegetation mats, peat rafts, aquatic floating-leaved and submergent macrophytes, and open water. A false-bottom of unconsolidated peat overlies the lake bed. Vegetation composition is typically diverse in such lakes, which support species of both acidic and calcareous habitat affinities. We repeated a 1973–74 survey to assess changes in wetland flora after four decades. The recent survey yielded 218 vascular plant species, representing 66 families and 134 genera. The largest genus was Carex with 26 species. Forty species from the original survey were not relocated, and 97 species were found in the recent survey that had not been found in the original survey. Eriocaulon aquaticum, usually associated with oligotrophic waters, was common in the original survey and not found in the recent survey. Aerial photos were used to calculate the change in vegetation cover, revealing that floating vegetation mats and peat rafts expanded between 1970 and 2016. Nutrient loading from agricultural and residential land use within the watershed, in addition to the installation of a dam across the lake’s surface water outlet have likely contributed to the floristic and community structure changes seen in Thompson Pond.
ABSTRACT: Marshallia mohrii (Asteraceae) is a perennial forb endemic to grasslands in the southeastern United States. Despite having been listed as federally threatened for three decades, little is known about its biology and life history. In this study, we examined the role of light, temperature, seed age, and cold stratification on seed dormancy break and germination in M. mohrii. We also quantified soil temperatures in a Ketona glade population of M. mohrii to infer dormancy breaking and germination phenologies under natural conditions. Relatively high proportions (>65%) of cold stratified seeds germinated across a range of temperature regimes in both light and darkness, whereas nonstratified seeds only germinated to high proportions in light at high temperatures. Germination proportions of laboratory stored seeds were slightly greater than freshly matured seeds, but remained much lower than those of cold stratified seeds. According to laboratory experiments, both autumn and spring germination phenologies are possible depending on the temperature and light conditions seeds experience after dispersal. Seeds of M. mohrii exhibited type 3 non-deep conditional physiological dormancy, which has been found in other members of Asteraceae from temperate grasslands. Overall, the germination niche of M. mohrii is defined by conditional seed dormancy, reduced dormancy levels following cold stratification, dark germination after dormancy loss, seasonal germination cueing, and seed traits consistent with short-term persistence in soil. Results from our study are useful for future conservation and recovery actions with M. mohrii and represent the first known published report of germination traits in this genus, which contains
Abstract: Seed mortality due to low winter temperatures has been proposed as an explanation for the lack of seedling recruitment in natural populations of the rare riparian species Alnus maritima, but other factors such as the absence of essential root symbionts or canopy clearing disturbances could also limit establishment of new individuals. We investigated whether any of these factors could be identified as preventing recruitment into existing seaside alder populations. Stratification studies showed that not only can seeds withstand low temperatures, longer periods of cold stratification promote earlier seed germination and expand the temperature range for germination. Root microbiome studies unexpectedly found that seedlings inoculated with the native microbiome prior to planting had lower survival compared to uninoculated individuals, and uninoculated individuals declined in survivorship after natural inoculation in the field. Canopy disturbance by burning or clipping vegetation promoted neither seedling growth nor survival initially, with seedling survival lower in burned plots due to the release of an aggressively growing competitor. Our results show that physiological stress by microbial symbionts and competition with other species are likely primary limiting factors—more so than seed mortality from low temperatures—and should be the focus of future conservation efforts.
Conyza ramosissima Cronquist (ASTERACEAE) Page County: Rocky slope along road, 5 mi. NW of Luray, 20 June 1950, Bernard Mikula 5222 (FARM). Significance: This is the first report of Conyza ramosissima (syn. Erigeron divaricatus Michaux) from Virginia. The specimen collected by Mikula establishing this record was encountered in the course of a study of herbarium material of C. canadensis (L.) Cronquist to distinguish its varieties [var. canadensis and var. pusilla (Nuttall) Cronquist] as they occur in Virginia; Mikula’s specimen had been initially identified as Erigeron canadensis L. Conyza ramosissima is best distinguished from other species in the genus by its profusely branched habit, generally lacking a well-defined main stem, its relatively low stature, usually ranging 1–3 dm tall, and strigose stem pubescence (Fernald 1950; Strother 2006). It also has distinctive white-margined phyllaries that lack the characteristic green tips found in C. canadensis var. canadensis or the red to purple tips typical of var. pusilla. In all respects, Mikula 5222 matches typical Conyza ramosissima. Examination of Conyza from FARM, GMUF, JMU, LFCC, LYN, ODU, URV, VPI, and WILLI failed to reveal any other specimen of Conyza ramosissima from Virginia, nor are specimens of this species held at the Shenandoah University herbarium (Woodward Bousquet, pers. com.). While geographic data for Mikula’s specimen are somewhat vague, the fact that Massanutten Mountain and the George Washington National Forest dominate the landscape northwest of Luray, Virginia, limits the likely locations for his roadside collection. Searches in the vicinity of all accessible pullouts on Rt. 675
Noteworthy Collections: The First Occurrences of Chevreulia acuminata (Gnaphalieae, Asteraceae) in North America
ABSTRACT: Chevreulia acuminata is reported for the first time in North America from recent collections in the southeastern United States. Populations from Lee County, Alabama, and one in Troup County, Georgia, were found growing in lawns or grassy areas along with other weeds. Photographs and a description of C. acuminata are provided.
Partial-root Harvest of American Ginseng (Panax quinquefolius L.): A Non-Destructive Method for Harvesting Root Tissue for Ginsenoside Analysis
American ginseng (<i>Panax quinquefolius</i>) roots have long been harvested for use in herbal medicine. Overharvesting has threatened long-term viability of wild American ginseng populations. Research has been ongoing to determine factors affecting the variation of ginsenosides in roots. Given the conservation concerns regarding wild American ginseng, we began experimenting with a partial-root harvest method in 2014 for extracting tissue for ginsenoside analysis without killing individual plants or causing long-term declines in wild populations. We took partial-root harvest samples from 57 plants in four wild populations throughout western North Carolina and monitored morphological attributes of these and 56 paired, unharvested plants of similar size for four years after harvest. Partial-root samples were taken from an additional 162 plants from 16 new populations in 2015 and 2016. Morphological attributes of these plants were monitored annually or biannually. In the paired plant study, annual reemergence did not differ between harvested and unharvested plants in any year after harvest. Leaf area was significantly lower in harvested plants than unharvested controls in the first year postharvest, but these differences did not persist after the first year. In the unpaired study, preharvest-postharvest comparisons were more variable, likely due to different harvest years and interannual variation in weather. Our results demonstrate that partial-root harvest could be an effective way for ginsenoside researchers to reduce their impact on wild and cultivated American ginseng populations and it may represent a non-destructive harvest protocol for root tissue phytochemical analysis.