Volume 84 – Issue 2 (Nov 2019)

Book Review — Southeastern Grasslands: Biodiversity, Ecology, and Management

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

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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

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Flora Re-survey After Four Decades in a New York Bog Lake

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

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The Genetic Diversity and Population Structure of Geum radiatum: Effects of a Past Augmentation of an Endangered Hexaploid

ABSTRACT Geum radiatum is a federally endangered high-elevation rock-outcrop endemic herb that is widely recognized as a hexaploid and a relic species. Little is known about G. radiatum genetic diversity, population interactions, or the effect of past augmentations of populations. This study sampled every known population of G. radiatum and used microsatellite markers to measure genetic diversity and population structure. The analysis demonstrates that there is interconnectedness and structure among populations. In addition, the analysis was able to differentiate transplanted individuals and identify putative anthropogenically admixed individuals within augmented populations. Geum radiatum exhibits diversity within and among populations and current gene flow connects the northern populations. This information provides a greater understanding of the genetic sustainability of G. radiatum and what conservation efforts will most help this imperiled species to survive.

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Scientific Note: Facultative Perenniality in the Dwarf Sundew (Drosera brevifolia)

Please note that the initial PDF issued was paginated incorrectly.  The correctly paginated article appears at this link. ABSTRACT: The dwarf sundew (Drosera brevifolia) occurs from Uruguay to Virginia. Disjunct populations occur in the southeastern U.S. with the northernmost in Kentucky. Despite this wide distribution, relatively little is known about the biology of this species. It has been described as both annual and biennial. The endangered Kentucky population is considered biennial, but occasionally, live, mature plants have dead flower stalks in early autumn suggesting some may be perennial. In 2013, 40 sundews that germinated in the fall of 2012 were marked as they flowered in 2013. They were observed into a third growing season in 2014 until the end of July. Sixteen plants (40%) died after setting seeds in their second growing season, while nine (22.5%) remained alive, flowered, and set seeds again the following year. Seven of these were

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The Demography of Gentiana autumnalis in Populations Under Varying Management Regimes in New Jersey

Please note that the initial PDF issued was paginated incorrectly.  The correctly paginated article appears at this link. ABSTRACT: Gentiana autumnalis (pine barren gentian) is a rare, fall-flowering perennial that is endemic to pine barren habitat from New Jersey to South Carolina. This disturbance-adapted, early successional species is at risk in New Jersey as a result of human interactions, namely growing season mowing and fire suppression. We used a repeated measures design to compare the differences between managed (mowing and prescribed fire) and unmanaged G. autumnalis populations for density, life stage, mortality, and fecundity. Managed populations had a greater gentian density, proportion of reproductive individuals, and seedlings compared to unmanaged populations. Implementing prescribed burns and mowing at previously unmanaged sites prior to spring growth increased gentian density, flowering, and seed set the same year. Our data support that prescribed burning and mowing can be beneficial management tools for the conservation

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Aquatic Vegetation of Springs at Buffalo National River, Arkansas

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,

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Germination Traits in the Threatened Southeastern Grassland Endemic, Marshallia mohrii (Asteraceae)

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

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