132 FLORIDA GEOLOGICAL SURVEY-SEVENTH ANNUAL REPORT. 
EXPLANATION OF THE VEGETATION MAP. 
By way of explanation of the map it may be said that the chief 
timber growth of this area is the long-leaf pine, Pinus palustris, 
and the term. “Pine lands/’ as commonly used in the section, refers 
to lands on which this species of pine predominates. Several other 
pines are present, but they are in no case so widespread, nor do they 
dominate the timber growth in the section in which they occur as 
does the long-leaf pine. The pine lands in turn are classed on the 
basis of topographic, drainage and soil conditions as “rolling pine 
lands” and “-flatwoods.” The rolling pine lands include the more 
or less undulating well-drained country over which the principal 
timber growth is the long-leaf pine. The top soil to the depth of 
a few inches is prevailingly gray owing' to the presence of organic 
matter mixed with light-colored sand. A few inches beneath the 
surface the soil becomes ochre yellow in color. At this depth also 
it retains sufficient clay> particles or silt to give it a loamy texture. 
The soils of this type of country are placed chiefly in the Norfolk 
series. Three grades of high or rolling pine lands are shown on the 
map as follows: Open pine, pine with black jack undergrowth, and 
pine with turkey oak undergrowth. 
The flatwoods include the level and hence poorly drained pine 
lands. Two distinct types of flatwoods vegetation are recognized, 
namely, the palmetto (including gallberry) flatwoods, and open 
flatwoods. In the palmetto flatwoods the chief timber growth is 
the long-leaf pine and related species. The undergrowth includes 
an abundance of saw palmetto, and locally of gallberry. The land 
is poorly drained, the water table being as a rule near the ground 
surface. The top soil is usually light-colored, although in places it 
contains sufficient organic matter to give it a dark color. At a 
depth of 12 to 24 inches the light-colored sand, practically without 
exception, passes abruptly into a dark chocolate sand stratum of 
several inches thickness known as hardpan, which grades below into 
light-colored sand. The open flatwoods differ from the palmetto 
flatwoods in that there is almost no undergrowth other than the 
heavy mat of wire-grass. This land is less well drained than is the 
palmetto flatwoods, and the soil contains for this reason a consider¬ 
able admixture of organic matter. Hardpan is rarely, if ever, found 
underlying the open flatwoods. In the area covered by this report 
the open flatwoods find but a limited development, being largely 
confined to a small section in the extreme northeastern part of the 
area. Practically all open flatwoods soils must be drained before 
