Soil is a thin surficial layer of loose material derived by weathering processes from the rock below. Its character depends on the mineralogy of that rock, and on climate and plant cover. Engineers commonly identify a material as a soil regardless of its organic content; however, many soil scientists insist that soil must contain at least some organic matter.
Soils in Florida vary locally but are generally sandy, excessively well drained, and low in fertility. The more organic soils are found in areas of low elevation where wetlands occur. Florida's most fertile soils are in upland regions of northern Florida, once an area of thriving plantations, and south of Lake Okeechobee, where sugarcane and winter vegetables are grown.
A modern and widely used soil classification, prepared by the United States Department of Agriculture, is followed here. It identifies soil types having differences in degree of development and nature of the various horizons. These are the A (or upper) horizon, consisting of organic matter mixed with rock material; the B horizon (underneath A), which has been enriched by humus, calcium carbonate and iron and/or aluminum oxides carried downward by water from A; and the C horizon (bedrock).
