13. WAKULLA HAMMOCK COUNTRY. 289 



13. WAKULLA HAMMOCK COUNTRY. 

 (figures 76-78) 



References — Smith 2, p. 227 (a few notes on vegetation, evidently derived 

 from Eagan's pamphlet). Illustrated in 3d Ann. Rep. pi. 21. i; 4th, Fig. 13. 



Confined to the central part of Wakulla County, or nearly 

 so, this little region has an area of perhaps 150 square miles. 

 There seems to be nothing exactly like it elsewhere. 



Geology and Soils — This region, like the preceding, seems to 

 be underlaid by Oligocene limestone, which pcotrpdes through 

 the soil in a few places in much the same way, and crops out 

 around a few sinks. At a deep sink containing water, a mile or 

 two south of Wakulla Spring, there is a little reddish clay over- 

 lying the limestone, but no other exposures of clay are known to 

 the writer. The prevailing soil is an exceptionally coarse sandy 

 loam, with not enough clay to make it coherent. Samples were 

 taken by the writer on Oct. 8, 1914, from the same spot shown in 

 Fig. 77, representing the first and third foot from the surface, 

 and there is no perceptible difference between the two except a 

 small amount of organic matter in the surface soil. Both are 

 light brown or buff in color. A partial mechanical analysis has 

 been made by the writer, with a series of sieves having apertures 

 I, ^, and % millimeters in diameter, respectively, with the fol- 

 lowing results : 



Soil Subsoil 



Fine gravel (above i mm.) 12.3 10.7 



Coarse sand (1-.5 mm.) 35.7 37.9 



Medium sand (.5-. 25 mm.) 40.0 40.3 



Fine sand, silt and clay (.25-0 mm.) 12.0 11. i 



Total loo.o loo.o 



Unfortunately it was not feasible to separate the silt and clay, 

 but these figures at least show the remarkably high proportion of 

 gravel and coarse sand. This coarseness is not strictly confined 

 to the region under consideration, though, for neighboring por- 

 tions of regions 9 and 12 seem to have coarser soils than the av- 

 erage for those regions. (No explanation for this state of affairs 

 can be suggested at the present writing.) 



Although this is one of the coarsest soils in Florida, it is also 

 one of the richest. The sample was selected from a patch of ap- 

 parently virgin forest in which the trees are nearly all deciduous; 

 and if the same correlations between soils and deciduous trees 



