HILL PRAIRIES AND PRAIRIE REGION. 99 
The ubiquitous bush clovers, Japanese clover, and tick-trefoils in a 
large measure take possession of the drier and lighter soil in the post 
oak woods. 
Where the limestone strata come near to the surface and the soil is 
not of sufficient depth to support a heavier tree growth, the oaks and 
hickories give way to copses of small trees and shrubs, among which 
hawthorns of different species are most abundant. Characteristic 
species are: 
Crataegus coccinea (scarlet haw.)} Prunus umbellaia (prairie plum). 
Crataegus molle (black thorn) .! Bumelia lycioides (false southern buck- 
Crataegus crus-galli (cockspur thorn) .1 thorn). 
Crataegus fiara (summer haw.) Rhamnus caroliniana (Carolina buck- 
Crataegus viridis (red haw.) thorn). 
Pyrus angustifolia (southern crab apple). Ptelea trifoliata (trefoil hop tree). 
These coppices form isolated boskets in the open or skirt the post- 
oak prairies, and when covered in the spring with the snowy white 
flowers of hawthorns, plums, and crab apples or adorned in autumn 
with their lurid red and flaming scarlet fruits, impart to the landscape 
a peculiar charm, relieving the monotony of the interminable fields 
of cotton. 
fill prairies.—On the hills bordering the plain northward and 
southward and on the highest ridges within the plain, capped like the 
hills with drifted siliceous deposits, the short-leaf pine mingles with 
the hard-wood trees, while the longleaf pine makes its appearance on 
the most abrupt of their summits. Where on these hills the drifted 
soils have been removed by denudation, the rich black soil of the 
prairies or calcareous marls prevails, covered either with the white 
oaks and hickories, or with cedar hammocks. These so-called hill 
prairies are mostly under cultivation, and the abandoned exhausted 
fields have been taken possession of by shortleaf and loblolly pine. 
East of the Alabama River, particularly on the divide between the 
waters of the Tallapoosa and those of the tributaries of the Chattahoo- 
chee, Choctawhatchee, and Conecuh rivers, the plain becomes broken 
into low hills, and the drifted deposits mingle largely with the soils 
of the rotten limestone. On these hills the timber growth, through 
the frequent interspersion of the shortleaf pine, assumes the same 
mixed character which prevails in the adjoining upper division of the 
Maritime pine belt. 
In the ravines and the narrow valleys the Southern spruce pine 
(Pinus glabra) with magnolias and cucumber trees is of frequent 
occurrence. 
MESOPHILE FORESTS. 
Prairie region.—The term ‘‘prairie region,” applied to this plain, 
refers less to the timberless tracts which originally formed a small 
fraction of its area than to the black, calcareous, highly fertile soil of 
1 Rarely found north of the Central Pine belt. 
