342 BOTANICAL GAZETTE [may 



some 



recently undisturbed; likewise on some of the old and extensive 

 estates groves have been preserved and illustrate what the forests 

 may have been before the civil war. Clearing and exhaustive 

 cotton growing soon reduce the humus and bring about soil vitia- 

 tion, which exposure intensifies, resulting in a more xerophytic 

 state. 



The exposed Orangeburg soil readily washes, and plants can 

 get a hold on the steep bare slopes with difficulty. Soil lichens 

 and mosses, however, soon form a gray-green coating, especially if 

 partially shaded. Species of Cladonia and Baeomyces are among 

 these earth lichens. 



Fields relapsing from tillage soon grow a mixture of ruderals 

 and native plants. Cenchrus carolinianus Walt., C. tribidoides L., 

 Erianthus divaricatus Hitch., E. brevibarbis Michx., Andropogon 

 virginicus L., A. Elliottii Chapm., A. scoparitts Michx., Gerardia 

 purpurea L., G. fasciculata Ell., G. tenuifolia Vahl., A plo pappus 

 divaricatus Gray, and Eupatorium capillifolium Small, with pros- 

 trate species of Rubus (R. trivialis Michx. and R. cuneifolius 



common 



with 



Of 



these pines, P. echinata Mill, (short-leaved yellow pine) is by far 

 the most abundant, although other species occur, as P. Taeda L. 

 (loblolly or old-field pine), P. caribaea Morelet (Cuban or slash 

 pine), and occasionally P. clausa Sarg. (sand or spruce pine), and 



palustris Mill 



Q 



Mill, (live oak) is a broad-leaved evergreen pioneer, and Diospyros 

 virginiana L. (persimmon) and Liquidambar Styraciflua L. (sweet 

 gum) are deciduous trees soon growing with the dominant pines. 

 Sassafras variifolium Ktze. and Prunus angustijolia Marsh, are 

 thicket formers. Pteris aquilina L. is an abundant fern character- 

 istic of these xerophytic pioneer stages of the old fields. 



The pines which spring up in such numbers, if not disturbed, 

 grow rapidly, and on the whole uniformly, and comparatively soon 

 form a forest of trees of similar height and diameter. Where burn- 

 ing or pasturing does not interefere, a dense shrubbery quickly 

 develops, including a variety of seedling trees and shrubs. Of these 



