(First entry, p. 38)
Leon County lies in the central part of North Florida. There are two topographically distinct divisions in the county--a northern upland section and a southern area of lesser elevation. The line dividing the two sections crosses the county in a zigzag course from east to west, a few miles south of Tallahassee.(1) The rolling country of the northern section, which lies within the belt of red sandy clay hills of north Florida,(2) contrasts sharply with the level pine lands in the south that are broken only by a few low sand hills and gentle swells. Surface elevations range from 100 to 250 feet above sea level in the north, but probably drop as low as 50 feet in the south.(3)
The only stream of any size is the Ochlockonee River, which forms the western boundary of the county. The entire area apparently at one time was drained by normal surface streams. Its topography has been materially affected, however, by underground solution of the underlying limestone, and the consequent subsidence of overlying materials, which resulted in the formation of numerous lakes and sinks. Drainage is now chiefly by means of underground streams flowing from limestone sinks.(4) The more important of these lakes are Iamonia, Jackson, and Lafayette.(5) An extensive area in the southwestern portion of the county is so level as to be imperfectly drained.(6)
The topographical differences in the two sections of the county are [paralleled] by differences in soils and forests types. The characteristic soil in the hill section is a phosphatic red, loamy clay which, before the days of commercial fertilizers, was the chief agricultural soil in Florida.(7) A more or less loamy deep sand, varying in color and
1. E. H. Sellards and Herman Gunter, “The Underground Water Supply of West-Central and West Florida,” Florida State Geological Survey, Annual Report, 1912, p. 133.
2. E. H. Sellards, “Geology between the Ocklocknee and Aucilla Rivers in Florida,” Florida State Geological Survey, Annual Report, 1917, p. 95.
3. Sellards and Gunter, op. cit., p. 133.
4. Sellards, “Geology between the Ocklocknee and Aucilla Rivers,” pp. 95-96.
5. For a description of these lakes, see E. H. Sellards, “Some Florida Lakes and Lake Basins,“ Florida State Geological Survey, Annual Report, 1910, pp. 53-57.
6. Sellards and Gunter, op. cit., p. 136.
7. Roland M. Harper, “History of Soil Investigation in Florida and Description of the New Soil Map,” Florida State Geological Survey, Annual Report, 1926, p. 37.