The relation of climax vegetation to islands and peninsulas 
RoLtanp M. HARPER 
Lake Tsala Apopka, in the eastern part of Citrus County, 
Florida, is a shallow irregularly shaped sheet of water about 15 
miles long and 5 miles wide, lying parallel to the Withlacooche 
River, just about on the line between the lime-sink and Gulf 
hammock regions.* Its bed and shores, like most of the surface 
of central Florida, are composed of sand presumably many feet 
in depth, covered with a little humus or peat in certain spots, but 
mostly fully exposed to the light. The topography in that part 
of the state is determined not so much by subaerial erosion as by 
irregular solution of the limestone which underlies the sand, and 
undulates in such a way as to give the lake an extremely sinuous 
outline.t This lake is so interspersed with islands and peninsulas 
that there is probably no point on its shores from which more than 
a few hundred acres of water can be seen at one time, even at its 
highest stage. 
The country bordering the lake, on the west side (I have never 
been on the east side) is of the type known in Florida as ‘‘high 
pine land’’; which means that it is covered with open forests of 
long-leaf pine, Pinus palustris (which is probably more abundant 
in central Florida than all other trees combined), with a fairly 
dense undergrowth of grasses and other herbs—most of them with 
small or narrow leaves—almost no shrubs or vines, and no mosses 
or lichens on the trees. Probably the most striking difference 
between long-leaf pine forests and other kinds is the scarcity of 
shade, and the other differences are in large measure correlated 
with this. 
On January 21, 1909, when Lake Tsala Apopka was so low 
that one could make many short-cuts across its embayments (as 
is usually the case with Florida lakes in winter), I walked past or 
* See Ann. Rep. Fla. Geol. Surv. 3: 221, 222. pl. 16. 
+ This peculiar topography is brought out very plainly on the Tsala Apopka 
topographic sheet of the U. S. Geological Survey (surveyed in 1893 and published 
in 1895, on a scale of about an inch to the mile). 
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