Biological Hotspots and Endangered Ecosystems

More than any other attribute, except perhaps pure aesthetics, discovery is what makes natural history so irresistible to naturalists. Given its impressive biodiversity, the South holds many rewards for professional and amateur naturalists who take the ti

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Biological Hotspots and Endangered Ecosystems

The grass grows three feet high. And hill and valley are studded all over with flowers of every hue.The flora of this section of the State and thence down to the sea board is rich beyond description. Mississippi Congressman John F. H. Clairborne (1841)

More than any other attribute, except perhaps pure aesthetics, discovery is what makes natural history so irresistible to naturalists. Given its impressive biodiversity, the South holds many rewards for professional and amateur naturalists who take the time to explore their backyards and beyond. The South has been traveled extensively by botanists, zoologists, and other naturalists for centuries, yet every year species new to science are discovered here. Whereas some new species are “split” from previously recognized taxa on the basis of newly discovered differences, other new species are completely new in the sense of never having been recorded before.These are usually narrow endemics discovered in a place that no previous naturalist with sufficient taxonomic expertise had explored intensively.

DISCOVERING LOST WORLDS Finding a species completely new to science is a privilege reserved for the very skilled and the very lucky. In 1992 Georgia botanist Jim Allison was conducting surveys in Alabama for a rare plant, Georgia rockcress (Arabis georgiana). Allison 73 R.F. Noss, Forgotten Grasslands of the South: Natural History and Conservation, DOI 10.5822/978-1-61091-225-9_3, © 2013 Island Press

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Forgotten Grasslands of the South

and three friends were canoeing down the Little Cahaba River in central Alabama, on the southern fringe of the Ridge and Valley Physiographic Province, where they were delighted to find several previously unknown populations of Coosa Barbara’s-buttons (Marshallia mohrii), a federally threatened species, disjunct from its main distribution in the Coosa prairies of northeastern Alabama and adjacent Georgia. This was exciting enough. But then they noticed, high above the bank of the river, a rocky slope dominated by grassland (plate 11). There were scattered longleaf pines and other woody plants, including eastern redcedar (Juniperus virginianus); chinkapin oak (Quercus muehlenbergii); dwarf palmetto (Sabal minor); Missouri maidenbush (Leptopus phyllanthoides), which is disjunct in Alabama from further west; and the rare Alabama croton (Croton alabamensis var. alabamensis). Mostly, however, the site was very open, with considerable exposed rock and a sparse groundcover dominated by little bluestem (Schizachyrium scoparium). In general appearance, the site that Jim Allison and friends discovered along the Little Cahaba resembled the limestone “cedar glades” of Tennessee, Kentucky, Alabama, and Georgia. Closer inspection, however, revealed that this site was different and of enormous biological value, surpassing even the famously endemic-rich cedar glades of the Central Basin of Tennessee. Subsequent surveys, aided by inspection of topographic maps (on which glades show up as irregular white patch