KUCHLER TYPE DESCRIPTION
Kuchler Type: Palmetto prairie


PHYSIOGRAPHY : 
Palmetto prairie is characterized by a lack of topographic relief
[3,30].  The hydrology of flatwoods and palmetto prairies varies with
elevation and topography.  In palmetto prairies, the water table is
typically 3 feet (1 m) below the surface during the dry season, and many
inches deep during the wet season, but may be above the surface for
brief periods of flooding [3].

Palmetto prairie at Myakka River State Park ranges in elevation from
35 to 40 feet (10.7-12.2 m) above mean sea level [13].


CLIMATE : 
The humid, subtropical climate of southern Florida is more affected by
the Atlantic Ocean and the Gulf of Mexico than by continental air
masses.  Mean annual precipitation is around 50 inches (1,250 mm), at
least two-thirds of which falls between May and October.  The winter is
relatively dry.  Mean annual temperature is 73 degrees Fahrenheit (22.7
deg C) just north of Lake Okeechobee [2,12].  The mean summer
temperature is only 12 degrees Fahrenheit (6.6 deg C) warmer than the
mean winter temperature.


SOILS : 
Palmetto prairie soils are typically deep, acidic, nutrient-poor, quartz
sands [3].  Soils are either well-drained Entisols, moderately
well-drained Spodosols, or poorly drained Inceptisols [2].  They contain
few weatherable minerals and usually contain very little clay.  Nutrient
storage and availability are highly dependent on the amount and type of
organic matter present.  The organic content of most soils is low,
except where stands have remained unburned for long periods of time.
Nutrient leaching rates are high; nutrient cycling is likely to be
almost imperceptible.  The water table in palmetto prairie is commonly
subject to extreme fluctuations, but flooding is rare, although some
areas occasionally experience temporary flooding [3].

Many palmetto prairie areas contain a spodic horizon, occasionally
underlain by a clay hardpan.  The hardpan reduces already poor drainage
and contributes to the development of the spodic horizon.  In extreme
cases the hardpan restricts root growth [3].

Davis [12] described saw-palmetto or flatwoods dry prairies (hereafter
referred to as palmetto prairie) as being typically associated with
ground-water podzols, mostly on Leon and Immokalee fine sands and some
on half-bog soils.  Davis also stated, as have other authors, that the
soils of pine flatwoods and palmetto prairie are essentially similar.
The average whole profile pH for the pine flatwoods-dry prairie complex
is 5.26 for Immokalee sands, ranging from 4.60 at the surface to 6.90 at
the bottom of the soil profile.  The prairie phase is usually more
acidic than the pine phase [12].


VEGETATION : 
Palmetto prairie is a diverse community; Hilmon [60] listed nearly 200
plant species that occur in palmetto prairie.  However, a relatively few
species form the bulk of palmetto prairie biomass [4].  According to
Kuchler [30] the dominant vegetation of palmetto prairie consists of
pineland threeawn (Aristida stricta) and saw-palmetto (Serenoa repens).
Other vegetation includes (in alphabetical order by scientific name)
bluestems (Andropogon spp.), bottlebrush threeawn (Aristida
spiciformis), tropical carpetgrass (Axonopus compressus), big
carpetgrass (A. furcatus), staggerbush (Lyonia fruticosa), fetterbush
(Lyonia lucida), knotgrass (Paspalum distichum), cabbage palmetto (Sabal
palmetto), and ground blueberry (Vaccinium myrsinites) [30].  Some
additional species listed as associates of pineland threeawn and
occurring in palmetto prairie communities include bracken fern
(Pteridium aquilinum) and dwarf huckleberry (Gaylussacia dumosa) [11].
Many authors use the term "dry prairie" for the same vegetation
assemblage.  In this write-up, the term palmetto prairie has been
substituted for an author's usage of dry prairie where they appear to
refer to the same vegetation type.

Palmetto prairies may have a very sparse pine canopy.  Pine flatwoods
have essentially the same floristic components as palmetto prairie, but
with more pine [3].  Davis [12] described a palmetto prairie associated
with pine flatwoods as essentially the same as the pine flatwoods
without the pines.  Pine flatwoods understories usually contain bitter
gallberry (Ilex glabra), tall threeawn (Aristida purpurascens), rusty
lyonia (Lyonia ferruginea), and southern bayberry (Myrica cerifera) in
addition to the species mentioned by Kuchler [3].

The pine flatwoods described by Davis [12] contain either longleaf pine
(Pinus palustris) and slash pine (P. elliotii), or South Florida slash
pine (P. e. var. densa).  The association is dominated by pineland
threeawn and saw-palmetto.  Important forage species include the
carpetgrasses and thin paspalum (Paspalum setaceum).  Shrubs include
fetterbush, staggerbush, ground blueberry, bitter gallberry, running oak
(Quercus pumila), and pennyroyal mint (Pycnothymus rigidus).  Common
forbs include white marsh-pink (Sabbatia elliotii), tall mint (Hyptis
radiata), candyweed (Polygala spp.), button snake-root (Eryngium
aromaticum), boneset (Eupatorium spp.), blazing stars (Liatris spp.),
goldenasters (Chrysopis spp.), and goldenrods (Solidago spp.).  In the
Big Cypress region, soils are more calcareous than those further north
and support more cabbage palmetto, sawgrass (Cladium jamaicense),
southern bayberry, bitter gallberry, hairawn muhly (Muhlenbergia
capillaris), gulfdune paspalum (Paspalum monostadyum), and Panamerican
balsamscale (Elyonurus tripsacoides) [12].

Abrahamson and others [4] classified a number of plant communities,
three of which appear to be closely related to Kuchler's palmetto
prairie:  wiregrass flatwoods, palmetto flatwoods, and
gallberry-fetterbush flatwoods.  Wiregrass flatwoods are communities
where pineland threeawn comprises more than 50 percent of the ground
cover.  Saw-palmetto is typically dwarfed (as compared to saw-palmetto
in other associations); dwarf St. Johnswort (Hypericum reductum) is
present, as are dwarf live oak (Quercus minima), fetterbush, dwarf
waxmyrtle (Myrica cerifera var.  pusilla), staggerbush, blueberries
(Vaccinium spp.), tarflower (Befaria racemosa), and bitter gallberry.
Palmetto flatwoods are dense, vigorous stands of saw-palmetto 3.3 to 6.6
feet (1-2 m) tall with an open to dense overstory of slash pine.
Gallberry-fetterbush flatwoods have a well-developed and diverse shrub
layer with or without South Florida slash pine.  Fetterbush and bitter
gallberry are abundant; tarflower and staggerbush are conspicuous [4].
All of the abovementioned communities occur within the range of the
palmetto prairie suggested by Kuchler, and are similar enough that some
open stands are classifiable as palmetto prairie.  In fact, Wade and
others [57] classify dry prairie (equivalent to palmetto prairie) in the
pine flatwoods category and do not treat it separately.  They define dry
prairies as flatwoods that no longer contain trees, though perhaps some
of them have never contained trees.  Throughout this write-up, it is
assumed that understory characteristics and responses in pine flatwoods
are very similar to that of palmetto prairie, and discussion of pine
flatwoods is included in this report.


WILDLIFE : 
Palmetto prairie shares many vertebrate species with pine flatwoods and
scrubby flatwoods (described by Abrahamson and Hartnett [3] as occurring
in a vegetation mosaic with pine flatwoods, palmetto prairie, and other
types) [3].  Palmetto prairie is primary habitat for the threatened
Audubon's crested caracara (Polyborus planchus ssp. audubonii), the
endangered Florida grasshopper sparrow (Ammodramus savannarum ssp.
floridanus), the endangered Florida burrowing owl (Athene cunicularia
ssp. floridana) [6], and the locally rare black-shouldered kite (Elanus
caeruleus) [62].  It is also used by many other bird species including
turkey vulture (Cathartes aura), black vulture (Coragyps atratus),
common nighthawk (Chordeiles minor), and eastern meadowlark (Sturnella
magna) [3].

Herpetiles found in palmetto prairie include box turtle (Terrapene
carolina), southern black racer (Coluber constrictor ssp. priapus) [3],
and flatwoods salamander (Ambystoma cingulatum).  The oak toad (Bufo
quercicus) is found in longleaf pine forests where pineland threeawn is
present; it may also be present on palmetto prairie [36].

Mammals occurring in palmetto prairie include least shrew (Cryptotis
parva), cotton rats (Sigmodon spp.), eastern harvest mouse
(Reithrodontomys humulis), and eastern spotted skunk (Spilogale
putorius).  The red fox (Vulpes vulpes) occurs uncommonly [3].  The two
most common exotic vertebrates in palmetto prairie are the nine-banded
armadillo (Dasypus novemcinctus) and the wild hog (Sus scrofa) [3].


ECOLOGICAL RELATIONSHIPS : 
Palmetto prairie is a fire-dependent subclimax type, controlled by
edaphic conditions (water table fluctuation) and climatic factors
(winter drought), and maintained by frequent fire [2,3,12].  Steinberg
[51] suggested that too-frequent burning of scrub or pine flatwoods may
create palmetto prairie.  Many communities created by logging of
second-growth slash pine flatwoods followed by frequent fire and
continuous grazing, or by altered drainage patterns, are
indistinguishable from palmetto prairie [3].  There was a major pulse of
logging activity in the 1920's.  After logging of pine flatwoods, herbs
and shrubs regenerate but slash pine regeneration is suppressed.  The
combination of logging and fire eliminated seed sources, creating a
treeless expanse [3].

In southern Florida, palmetto prairies are interspersed with cabbage
palmetto flatwoods and often grade into wet flatwoods, savannas, or pine
flatwoods [3].  Wherever a dense layer of saw-palmetto exists, fire
frequency and severity are high and few young pines survive.  South
Florida slash pine seedlings, however, have a grass stage similar to
that of longleaf pine and are relatively resistant to fire [57].

Fire maintains the species composition and community structure of
palmetto prairie [3,13].  Long fire-free intervals allow succession to a
variety of vegetation types, dependent on climate, available seed, and
edaphic conditions [3].  Palmetto prairie might develop to low hammock
or pine flatwood if left unburned [43].  In Myakka River State Park, 35
years of fire suppression have led to shrub dominance of former palmetto
prairie [13].  See FIRE ECOLOGY AND MANAGEMENT for further discussion of
the ecological impact of fire and fire exclusion on palmetto prairie.

Related categories for Kuchler Type: Palmetto prairie