0 0.5 1.0 1.5 2.
J.M. JOHNSON, I.C. OLMSTED, OL. BASS, JR.
U. S. NATIONAL PARK SERVICE
EVERGLADES NATIONAL PARK
SOUTH FLORIDA RESEARCH CENTER
PINELAND. Open stands of slash pine (Pinus elliottii var. densa),
ranging to 20 m, with an understory typically very rich in species
including many of the tropical hardwoods found in hammocks as well
as Serenoa repens, Myrica cerifera, Ilex cassine, Persea borbonia,
Dodonea viscosa, and other tree and shrub species. Many forbs and
suffrutescent shrubs are present, of which 20 are endemic. The
substrate is jagged limestone with numerous solution holes and little
soil development. The elevations are higher than adjacent prairies
and are often as high as those of hammocks. Inundation is rare. The
pineland is maintained by fire.
PINELAND WITH TALL HARDWOOD UNDERSTORY. Pinelands that
have escaped recent fires, allowing the hardwoods in the understory
to reach heights of 8-10 m. The species composition is similar to the
pinelands, but pines no longer reproduce and forbs and endemic shrubs
are disappearing because of a deep layer of pine duff and increasing
TROPICAL HARDWOOD HAMMOCKS. Mixed stands with relatively
closed canopy consisting predominantly of tropical hardwoods includ-
ing Quercus virginiana, Lysiloma latisiliquum, Bursera simaruba,
Myrsine floridana, Ardisia escallonioides, and Eugenia axillaris, which
are found in the adjacent pineland, and Nectandra coriacea,
Coccoloba diversifolia, Simarouba glauca, and Mastichodendron
foetidissimum, found rarely outside hammocks. Tree heights range
from 6-17 m. Groundcover is sparse and epiphytes are common. The
limestone is covered by a thin layer (5-15 cm) of organic matter, and
solution holes are abundant. Elevations are as high as those of the
pinelands and ground surface is rarely, if ever, under water.
HARDWOOD SCRUB. Short hardwoods (to 6 m). In some ecotonal
areas along the transverse glades, where moisture and substrate
conditions are different from those of either pineland or glade,
Metopium toxiferum, Conocarpus erectus, Myrica cerifera, Ilex
cassine and Persea borbonia occur. Hardwood scrub also occurs in
early successional growth after fire inside tropical hardwood ham-
mocks, particularly in those surrounded by prairie. In addition to the
species just named, we encounter Trema micranthum, Quercus
virginiana and Bumelia salicifolia. Pteridium aquilinum is a constant
FARMED PRAIRIE WITH HARDWOODS. Former marl prairies which
were farmed and later abandoned. Now forested, these areas are
dominated by Ilex cassine, Persea borbonia, Myrica cerifera, and the
exotics Schinus terebinthifolius and Psidium guajava.
MUHLENBERGIA PRAIRIES. Fairly dry prairies in which the domi-
nant species is Muhlenbergia filipes with varying percentages of
Cladium jamaicense as well as a large assortment of other grasses,
sedges and herbs. The substrate is marl.
PRAIRIE WITH SCATTERED HARDWOOD SCRUB. Dominated by
graminoid species, with scattered hardwoods such as Ilex cassine,
Metopium toxiferum, Persea borbonia, and Myrica cerifera.
FARMED PRAIRIE WITH PRAIRIE SPECIES. Prairie that was
farmed for a short time and supports prairie vegetation again.
Furrows are still visible. Serenoa repens is common in some areas.
CYPRESS PRAIRIE. Prairie, characterized by various densities of
cypress trees (Taxodium distichum), often stunted, and dominated
more often by Cladium jamaicense than by Muhlenbergia filipes. The
soil is marl and a little deeper than in other prairies.
CYPRESS FOREST. Both cypress domes and heads, with overstories
of Taxodium distichum. Domes are in a depression with a long
hydroperiod and are nearly devoid of understory shrubs. Cypress
heads are on slightly elevated ground with a shorter hydroperiod, an
understory of Chrysobalanus icaco, Persea borbonia, Myrica cerifera
and Magnolia virginiana, and support frequent fires. Both have an
organic substrate. Epiphytes are plentiful.
WILLOW HEADS. Stands of Salix caroliniana often mixed with Thalia
geniculata and Phragmites australis, growing in depressions of glades
and prairies. Large willow heads are often surrounded by tall (2-3 m)
sawgrass (Cladium jamaicense), Pontederia cordata var. lancifolia
and Phragmites, and enclose ponds, 1-1.5 m deep.
OPEN WATER. Often "borrow pits" associated with road con-
HOLE-IN-THE-DONUT. Former pineland, hammocks and prairies
that were farmed and abandoned by 1975. Now in various success
sional stages, commonly dominated by weedy forbs and shrubs and the
exotic tree Shinus terebinthifolius.
45 HAMMOCK NUMBERS. (see list in text for corresponding names)
17 SECTION NUMBERS.
......... BROAD TRANSITION BETWEEN PINELAND AND PRAIRIE.
Plant communities were delineated on 9 in. x 9 in. color aerial photo
raphs (1:7800). The details were transferred to a skeleton ma
(1:18,000), which was generated from USGS 7.5 minute orthophol
quadrangle sheets, using a Map-O-Graph opaque projector. Plan
communities largely correspond to those used by Davis (1943) ar
Craighead (1971). Ground-truthing was done during February ar
March 1981. We thank Mr. Antonio 3urado of the Water Resource
Division, U.S. Geological Survey, for aid and consultation.
" m *