PHYSICAL CHARACTERISTICS OF HABITAT
(continued)
We collected a sample of topsoil from an open area on each of four glades and submitted them through the Cooperative Extension Service of Georgia (University of Georgia/Georgia Department of Agriculture) to the state Soil Testing Laboratory for routine analysis. These tests indicated that the soil derived from the weathering of Ketona Dolomite is very high in magnesium and calcium but low in phosphorus and potassium. The soil reaction is mildly alkaline, with a pH range from 7.4 to 7.6.
The climate of central Alabama is characterized by mild winters, with temperatures often falling below freezing at night but seldom remaining so all day, and warm, humid summers. The physical environment of the Ketona Glades, given its lower latitude, is presumably somewhat milder in winter and warmer in summer than the regions to the north in which glades occur.
The flora of the Ketona Glades is distinguished from those found in other glade, barren, or prairie habitats by containing eight endemic taxa, plus a number of species that are otherwise rare or unknown from glade habitats, along with many taxa well known to frequent such places.
The dominant grass species of the open glade is Schizachyrium scoparium (Michx.) Nash, but it usually does not achieve great density and is an aspect dominant only late in fall and winter, when the strong forb component is muted. Other characteristic plants of this community include Agalinis purpurea (L.) Pennell, A. tenuifolia (Vahl) Raf., Allium canadense L. var. mobilense (Regel) M. Ownbey,
Amsonia ciliata var. tenuifolia (Raf.) Woods., Andropogon gerardii Vitman, A. virginicus L., Asclepias viridiflora Raf., Callirhoë alcaeoides (Michx.) Gray, Castilleja Mutis ex L. f. sp. nov.,
Cnidoscolus stimulosus (Michx.) Engelm. & Gray, Fimbristylis puberula (Michx.) Vahl, Gaura filipes Spach, Hedyotis nigricans (Lam.) Fosb., Hypoxis hirsuta (L.) Coville, Isoëtes butleri Engelm., Leavenworthia exigua Rollins var. lutea Rollins, L. uniflora (Michx.) Britt., Leptopus phyllanthoides, Liatris Gaertn. ex Schreb. sp. nov., L. cylindracea Michx., Linum sulcatum Riddell var. sulcatum, Lobelia spicata Lam.,
Marshallia mohrii, Mecardonia acuminata (Walt.) Small var. acuminata, Minuartia patula (Michx.) Mattf., Mirabilis albida (Walt.) Heimerl, Nothoscordum bivalve (L.) Britt., Onosmodium Michx. sp. nov., Oxalis priceae Small ssp. priceae, Paronychia virginica Spreng., Penstemon tenuiflorus Pennell, Polygala boykinii Nutt.,
P. grandiflora Walt., Rhynchospora colorata (L.) H. Pfeiffer, Rudbeckia triloba L. var. pinnatiloba Torr. & Gray, Ruellia humilis Nutt., Sabal minor, Salvia azurea Lam., Schoenolirion croceum (Michx.) Wood, Scutellaria parvula Michx., Silphium L. sp. nov.,
Solidago ulmifolia Muhl. ex Willd., Spigelia gentianoides Chapman in A. DC. var. alabamensis K. Gould, Spiranthes magnicamporum Sheviak, Sporobolus junceus (Michx.) Kunth, Tetragonotheca helianthoides L., and Yucca filamentosa L. Also frequent is a moss, Pleurochaete squarrosa (Brid.) Lindb. Amsonia ciliata var. tenuifolia is often abundant and dense enough to be an aspect dominant in spring, and Rudbeckia triloba var. pinnatiloba is occasionally an aspect dominant in summer.