224 FLORIDA GEOLOGICAL SURVEY SIXTH ANNUAL REPORT. 



and then soak into the ground. Some of the eastern part of the 

 "valley" may be drained by Pine Log Creek. 



Vegetation Types — 'The original forest that remains, mostly on 

 steep slopes, consists of hardwoods and short-leaf pines, and is 

 rather "dense. In the second-growth woods the pine is relatively 

 more abundant, and dogwood is very common. The sloughs and 

 ponds have the vegetation usually found in such places where the 

 soil is pretty rich. Fire is a negligible factor, as in other fertile 

 regions with dense forests and a large proportion of cleared land. 



Plants — These have already been listed in connection with those 

 of the Knox Hill country, as above explained. Most of the remarks 

 about the plant list of that region will apply also to this. One shrub 

 in the list. Viburnum densiflorum, has not been seen by the writer 

 outside of Holmes Valley, but it differs very little from V. acerifol- 

 ium, a species characteristic of rich woods in the Piedmont region of 

 Georgia and Alabama. It is noteworthy tl:^at less than 2 per cent of 

 the shrubs observed in Holmes Valley are Ericaceae, which is quite 

 a different state of affairs from that in the Knox Hill country. No 

 Leguminosae whatever were noticed here, but a visit to the region in 

 late summer or fall would doubtless reveal a few members of that 

 family. Short-leaf pine (P. echinata) , birch, black-jack oak (both 

 kinds) and ashes are perceptibly scarcer here than in the Knox Hill 

 country. 



Economic Features — Although this region is mostly under culti- 

 vation, it seems to be an illustration of the general principle that in 

 the southeastern United States, if not elsewhere, the most fertile 

 regions are not the most salubrious.* For this reason, and probably 

 also on account of the scarcity of running water, most of the farmery 

 who till its fields (the majority of them negroes, apparently) live 

 just outside of the "valley," either north or south of it. Cotton and 

 corn are the prevailing crops, as usual. No important use seems 

 to be made of the remaining native vegetation. 



*This correlation seems never to have been satisfactorily explained. 

 The mosquito theory of malaria, perfected in lyoo, explams it partly, 

 but not entirely. 



