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NATURALIST'S GUIDE TO THE AMERICAS 



tion varies considerably according to the 

 prevailing types of soil. In sections 

 where loamy soils prevail the predomi- 

 nant tree, under present conditions, is 

 loblolly pine, but in sandy soils this is 

 very largely replaced by longleaf pine. 

 In the Piedmont portion of this zone 

 mesophytic hardwoods, such as white 

 and black oak and hickories prevail, 

 whereas south of the Fall Line these 

 become relatively infrequent and are 

 largely replaced by more zerophytic 

 species, such as blackjack oak and post 

 oak. Longleaf pine was and, so far as 

 it has not been destroyed, is still the 

 dominant forest tree of the Altamaha 

 Upland — a region which has vegetational 

 features reminiscent of typical pine- 

 barrens. The same species also appears 

 to predominate on the Fall Line Sand 

 Hills. In the Red Hills section it is of 

 more local occurrence, being almost 

 entirely supplanted in this section by 

 loblolly pine. In general, the herbace- 

 ous flora north of the Fall Line has 

 closer affinities with that of the adjoin- 

 ing portions of the mixed hardwood 

 forest area (Upper Austral Zone) than 

 to that south of the same line. In the 

 Piedmont Region the soils are prevailing 

 neutral or faintly acid, while south of 

 the Fall Line distinctly acid soils are of 

 rather general occurrence. In the Pied- 

 mont, also, swamps and other per- 

 manently wet areas are rare and of 

 limited extent, whereas in the Coastal 

 Plain they are common and often of 

 considerable size. These swamps are 

 of two kinds, river swamps and upland 

 swamps. The river swamps border 

 the major streams while the upland 

 swamps form about the headwaters 

 of local streams. The river swamps 

 occupy alluvial flats and support a 

 luxuriant growth of trees of which the 

 more conspicuous and characteristic 

 forms are species of evergreen oaks, 

 as the willow-oak {Quercus phellos) 

 and water-oak (Q. nigra). The upland 

 swamps are of the nature of strongly 

 acid bogs in which such trees pre- 

 dominate as gums {Nyssa), sweet-bay 

 {Magnolia glauca), red maples and pond 



pines (P. serotina). The most interest- 

 ing flora of the southern mixed conifer- 

 ous and hardwood forest (Lower Austral 

 Zone) in Georgia is that found in the 

 Altamaha Upland (the Altamaha Grit 

 Region of Harper), where the conditions 

 approximate those of the typical south- 

 ern pine barrens. 



A Gulf Strip or Palmetto Belt (Saba- 

 lian Zone)- is recognized by Rehn and 

 Hebard, and is typically represented in 

 the Okefenokee and Satillo plains. As 

 intimated in one of the names, this 

 zone is co-extensive with the range of 

 the cabbage palmetto {Sahal -palmetto) 

 which forms the most characteristic 

 tree of the forests. The latter are 

 almost exclusively coniferous in com- 

 position, the dominant species being 

 longleaf and slash pine. This is a rich 

 faunal and floral region, with strong 

 affinities to Florida. The alligator is 

 largely limited to this zone, also the 

 diamond-back rattler, and such trees 

 as slash pine and live oak. Cypress is 

 abundant in the swamps, which are 

 often of great extent and tropical 

 luxuriance. Black bears and Virginia 

 deer are reported to exist in this section 

 in considerable numbers. On the im- 

 mediate coast maritine conditions pre- 

 vail, the tidal marshes supporting a 

 luxuriant growth of tall reeds in which 

 water-fowl of several kinds find a con- 

 genial home, while on the sea-islands 

 the sand dunes show characteristic 

 vegetational features. 



II. PRESENT BIOTIC CONDITIONS 



In Georgia human occupancy and 

 exploitation have for the most part 

 so completely altered natural conditions 

 that it is difficult to form a clear idea 

 of what these conditions were. Georgia, 

 like the other southeastern states, was 

 originally covered with an unbroken 

 forest, but this has been removed on 

 such an extensive scale, especially the 

 more valuable timber trees, that it 

 seems probable that present-day con- 

 ditions may be misleading. Thus, it 

 is a matter of common knowledge that 

 the dominant forest growth in central 



