Report SFRCStatus of Exotic Woo 

Species in Big Cypress 

National Preserve 

c+..., "I*, or 

Everglades National Park, South Florida Research Center, P.O. Box 279, Homestead, Florida 33030 
Status of Exotic Woody Species in Big Cypress National Preserve 

Report SFRC-83/07 

Lance H. Gunderson 

National Park Service 

South Florida Research Center 

Everglades National Park 

Homestead, Florida 33030 

December 1983 
Gunderson, Lance H. 1983. Status of Exotic Woody Species in Big Cypress National 

Preserve. South Florida Research Center Report SFRC-83/07. 22 p. 
TABLE OF CONTENTS 

. . LIST OF FIGURES ......................... 11 

INTRODUCTION .......................... 1 

Exotic Plants in South Florida .................. I 

Historical Information ..................... 2 

OBJECTIVES ............................ 4 

METHODS .............................. 4 

RESULTS AND DISCUSSION ..................... 4 

Melaleuca quinquenervia .................... 5 

Distribution ....................... 5 

Monroe Station Area ................. 5 

Paolito Station Area .................. 5 

Jetport Area ..................... 6 

Loop Road Area ................... 6 

Interior Pinelands Area ................ 6 

Ochopee Area .................... 6 

Turner River. Birdon and Wagon Wheels Road Areas .... 6 

Factors affecting establishment ............... 6 

Natural disturbances ................... 9 

Fire ......................... 9 

Hurricanes ...................... 9 

Frosts ........................ 10 

Water Consumption by Melaleuca .............. 10 

Schinus terebinthifolius ..................... 10 

Distribution ........................ 10 

Factors affecting establishment ............... 11 

Natural disturbances ................... 12 

Hurricanes ...................... 12 

Fire ......................... 12 

Casuarina sp .......................... 13 

Distribution ....................... 13 

Natural disturbances ................... 13 

Severe Storms .................... 13 

Fire ......................... 13 

Other Woody Exotic Species ................... 13 

CONCLUSIONS ........................... 14 

Melaleuca quinquenervia .................... 14 

Schinus terebinthifolius ..................... 14 

Casuarina spp .......................... 15 

Other Species ......................... 15 

ACKNOWLEDGEMENTS ....................... 15 

LITERATURE CITED ........................ 19 
LIST OF FIGURES 

Figure Page 

1 2 Location of fifteen, 1 mi quadrats within Big Cypress 

National Preserve surveyed by Alexander and Crook (1975) . . . . 16 

2 Areas surveyed by various methods to map distribution of 

woody exotic species in Big Cypress National Preserve . . . . . . 17 

3 Current (1 982) distribution of Melaleuca in Big Cypress 

National Preserve . . . . . . . . . . . . . . . . . . . . . . 18 
INTRODUCTION 

0 

The National Park Service (NPS) was assigned administration of the Big Cypress 

, National Preserve (BICY) in the 1974 congressional act which created the preserve 

-(PL 93-440). In this act, the NPS was charged with assuring that the "natural and 

ecological integrity" of the BICY would be maintained in perpetuity. One of the 

management objectives set forth by the NPS in the 1980 Environmental Assessment 

(USDI, NPS 1980) was to "control exotic plant and animal species when necessary 

to prevent disruption of native floral and faunal c~mmunities.~' In light of this 

objective, up-to-date biological information is needed on the problem species; 

especially which species pose problems, what are the distributions of the problem 

species, and what are the prognoses for these distributions in the current framework of environmental conditions in BICY??! 

Exotic Plants in South Florida /L 

Southern Florida is the only region of the continental United States where 

temperate and tropical floral elements coexist. High temperatures and rainfall 

create tropical conditions during the summer months. Infrequent freezes, associated with periodic winter cold fronts, prune-back cold sensitive tropical species. 

Temperate species are in a minority group comprising only 39 percent of the 

approximately 1650 species found in southern Florida (Long 1974). The bulk of the 

tropical species are herbaceous, but many native tropical t r e e s a r e present. 

Long (1974) determined that propogules of tropical species now in Florida must 

have crossed the sea because no land bridge existed between Florida and the 

Antillean area. Natural vectors such as birds, hurricanes, and ocean currents 

moved species to Florida. Also, some species may have been moved by early 

Florida inhabitants who traded with populations on the Carribean Islands. 

The species introduction rate was probably slow because of few species adapted to 

surviving such trips and the infrequency of conveyors such as hurricanes. With the 

advent of modern civilization, many thousands of plant species were introduced to 

south Florida. Botanists, working for the U.S. Department of Agriculture, traveled 

to many lands and brought back species to improve genetic stock for agriculture. 

Gardeners and horticulturists also introduced many species to decorate and 

landscape homesites and gardens. 

Since southern Florida is geologically young, there may be vacant niches for plant 

species. Species richness may not yet be optimized because of unique environmental conditions in south Florida and a naturally slow rate of species introduction. 

Therefore, it is possible that species introduced here may be able to compete and 

establish with the existing flora. Alteration of the landscape by water manipulation, land clearing, farming, etc., has no doubt favored these exotic plants, but 

these species also appear to exploit niches not optimized by native species (Myers 

1975). 

Duever et al. (1979) compiled a list of exotic plant species naturalizing in south 

Florida based on work of Austin (1978), Alexander and Crook (1975), Long and 
Lakela (19711, and Sturrock (1968). The Duever et al. (1979) list of 300 exotic 

species enumerates species that may be naturalizing in the preserve, and is 

probably an overestimate of exotic species actually in the BICY. Black and Black 

(1980) listed 645 species (both native and exotic) as occurring in BICY; 76 (12%) of 

which were considered to be exotic in origin. They (op. cit.) listed an additional 40 

species (all exotic) which persist from cultivation around homes and campsites. 

Therefore, based on the Black and Black report, roughly I out of every 7 plant 

specie-s in the BICY is exotic. 

Even though over 100 exotic species are currently in the BICY, only a handful have 

become conspicuous parts of the landscape. These few exotics are considered pests 

because of their ability to aggressively colonize a site (both native and disturbed) 

and to form virtually monospecific stands. The aggressive species in the BICY are 

Melaleuca quinquenervia cav. (Blake), Schinus terebinthifolius Raddi and Casuarina 

glauca Sieb. ex Spreng. Hereafter, in this report these species will be referred to 

by the genus name, lower case, and not underlined. 

There are other exotic pest plants in the BICY. The most wides~read s~ecies are 

the aquatic plants hyd;illa, '~~drilla verticillata, and water hyacinth, ~ichhornia 

crassipes. However, as Duever et al. (1979) point out, these species are largely 

restricted to the canals and borrow pits in the BICY, and are only rarely found in 

the native systems. These species probably do not pose an immkdiate'threat of 

displacing native vegetation and are not discussed in this report. For more 

information, the reader is referred to Duever et al. (1979). . Historical Information 

Early relerences about the vegetation on the BICY area do not mention exotic 

trees. Construction on US 41 was completed in 1928 so access prior to this time 

was probably limited. Davis (1943) does not mention any exotic trees in his primer 

on south Florida vegetation. Exotic species were around at this time though and 

largely restricted to coastal sites. Meskimen (1 962) dates the introduction of 

melaleuca in south Florida to be 1906 on the east coast (Davie) and 1912 at the 

Koreshen Nurseries near Estero on the west coast. Nehrling (1944) reports that 

schinus was introduced on the west coast of Florida around Bradenton sometime in 

the early 1900's. Morton (1980) dates introduction of casuarina as 1898. Casuarina 

is evident in photographs of the Ochopee area (within BICY) taken in the mid1930's (Nieland 1936). 

Most of the populations of melaleuca and casuarina in BICY can be traced to 

intentional plantings. Meskimen (1962) states that the stand of melaleuca at 

Monroe Station was planted in 1944. The originial trees are still present, and are 

found immediately south and west of the buildings at Monroe Station. Meskimen 

(1962) surveyed this site and found no regeneration into the surrounding area as of 

1958-59. Casuarina was planted for use as windbreaks, and probably as a safety 

barrier, between canals and roads by WPA projects in the 1930's. The stand along 

US 41 in Dade County has this history. The roadside stand also extended into 

Collier County, but was removed when the widening of US 41 was concluded in 

the early 1960's (Dayhoff pers. comm.). 
The expanding populations of exotic trees, especially melaleuca and schinus, were 

first documented by Alexander and Crook (1975). They mapped the vegetation on 

15-mile-square quadrats in the preserve (Fig. 1). In Section 11 (T535, R32E) (north 

of Monroe Station) Alexander and Crook in March 1973 found 6- to 30-ft.-tall (2- 

10m) melaleuca and 10-ft.-tall (3m) schinus in an abandoned farm field. The 

authors (op. cit.) found melaleuca on windrows left by bulldozing after farming, 

and on the periphery of a cypress strand. No exotics were identified on the map 

made from 1940 aerial photographs. In Section 22 (T54S, R33E) they (op. cit) found 

melaleuca establishing from roadside plantings into sparse cypress and low pinelands south of the loop road. In 1970, thickets of schinus dominated the heavily 

impacted farm areas in Sections 19 and 30 (T52S, R30E), as well as a severely burned 

hardwood stand. Notable from their accounts is the absence of exotic species from 

the interior (away from major roads) quadrats located within the BICY. 

Capehart et al. (1977) tried to map the distribution of melaleuca in southern 

Florida using LANDSAT imagery and computer-enhancement techniques. They 

could not find a characteristic spectral signature for melaleuca, as it was found in 

monospecific stands, or interspersed with pine, cypress, hardwoods, or mangroves. 

Each of these combinations results in a different signature, therefore, they could 

not accurately map the distribution. 

Sweet (19811, however, determined that melaleuca could be identified in a pinecypress vegetation mosaic by use of modified software in conjunction with 

LANDSAT imagery, but did not determine signatures of other melaleuca associations. Arvinitis (1978) thought false-color infrared photography would be useful in 

spotting melaleuca in various plant communities, but did not map distribution. 

Ewe1 et al. (19761, based on fieldwork of Myers (19751, predicted that melaleuca 

would not be a conspicuous part of the landscape, but that areas adjacent to US 41 

and Monroe Station may be locally dominated by this species. 

Duever et al. (1979) mapped the distribution 'of melaleuca, schinus, casuarina, 

hydrilla, and hyacinth in the preserve and found these exotics to be mostly confined 

to roadside stands. Melaleuca was found to be expanding from plantings at 

homesites along Turner River Road. Rapidly growing populations were also located 

at Monroe Station, Paolito Station, and at one site off the Loop Road (SR 94). 

Schinus was found in association with mixed swamp hardwoods in the Ochopee area, 

as well as throughout hardwood hammocks along the southern boundary of the 

preserve. 

Cost and Craver (1980) did an aerial survey of melaleuca distribution in southern 

Florida. They noted melaleuca in pure and mixed stands (with native vegetation) in 

the northern section of BICY, north of SR 84, an area where other authors have not 

found populations. Also, they did not locate any stands in the Monroe Station area, 

where known large stands do exist, leading one to question the accuracy of their 

survey. 
OBJECTIVES 

Two objectives were sought in this report: 

1. To document current distribution of problem exotic species (melaleuca, 

casuarina, and schinus) and note occurrence of any species perceived to 

be a potential pest species. 

2. To assess the stand dynamics for these exotic populations in the current 

framework of native plant communities and the disturbances that occur 

in the preserve. 

METHODS 

Many activities were done to compile the distribution map. All of the major roads 

in the preserve were surveyed, including US 41 (Tamiami Trail), SR 94 (Loop Road), 

SR 84 (Alligator Al,ley), SR 839 (Turner River Road), SR 841 (Birdon Road), and SR 

837 (Wagon Wheel Road) (Fig. 2). Off-road surveys were done by foot and by Honda 

ATC in the areas around Monroe Station and Ochopee. Vegetation maps of five (5 

x 10 km) areas in the preserve (Gunderson et al. 1980a; Gunderson et al. 1980b; 

Gunderson and VanHorn 1981a; Gunderson and VanHorn 1981b; and VanHorn and 

Gunderson 1981) were surveyed and used to locate exotic stands (Fig. 2). These 

maps were made from large-scale aerial photographs (1:7800) with extensive 

ground-truthing, s? they are fairly comprehefsive inventories of these areas. 

Aerial photographs (1:7800) of five other 50 km areas in the preserve were studied 

to locate large exotic stands (Fig. 2). Photographs were viewed wyh a magnifying 

stereoscope of resulting resolution so stands on the order of 100 m (0.01 ha) could 

be recognized. The photographs were made in spring and summer, when the 

cypress were leafed-out. Therefore, sub-cypress-canopy exotics could not be 

located by this method. For example, thickets of schinus in cypress-mixed 

hardwood swamps would not be detectable on the photographs. Melaleuca foliage 

appears as a darker green than the pine or cypress needles, and was, therefore, 

readily found on the photographs. None of these five study areas were checked on 

the ground. The other source of information on the distribution of exotics was Mr. 

Fred Dayhoff. He also supplied much information on recent (20-25 year) history of 

exotic plant spread based on personal knowledge and observation. Rangers Bruce 

Malloy and Robert Yates also added their knowledge of exotic plant location. 

RESULTS AND DISCUSSION 

The current distribution of woody exotic trees in the BICY is still largely restricted 

to roadside stands (map enclosed in back pocket of report). Letter symbols were 

used to represent each species as follows: M-melaleuca, S-schinus, C-casuarina. A 

letter is shown for each area of occurrence, regardless of stand size, density, or 

structure. In regions where the stand was expanding, such as the Monroe Station 

area, tall dense stands and scattered individuals of melaleuca were all enclosed 

within a single line and designated M. This was done because of the small scale of 

the map that covers the preserve, any actual depiction of stand size would be 

meaningless at this scale. 
Native plant associations referred to in this report include hardwood hammocks, 

pinelands, cypress-mixed swamp forests, cypress domes, cypress prairie, Muhlenbergia (muhly) prairie, and mixed aquatic marsh. For .more information on the 

description of these communities, the reader is referred to Duever et al. (19791, 

Gunderson et al. (1 982), and Gunderson and Loope (1 982a,b,c,d). 

Melaleuca quinquenervia 

Distribution 

Areas of concentrated stands of melaleuca may be grouped into seven units. Large 

trees (20-30 meters tall) are found in these areas, but stand size and tree density 

within each stand is variable. The areas are designated as Monroe Station, Paolito 

Station, Loop Road, Jetport, Interior Pinelands, Ochopee, and Turner River Road 

(Fig. 3). The map (Fig. 3) is by Fred Dayhoff and he is responsible for supplying 

much of the following information on stand size and history. 

Monroe Station Area. The original planting of melaleuca at Monroe Station is 

immediately south and west of the building complex. As of 1958-59 (Meskimen 

1962), no expansion was noticed from the original stand. Many disturbances have 

occurred in t h e a r e a since then and each has contributed to expansion from the one 

stand. Monument Lake and surrounding fill was created in the early sixties, in 

association with the widening of US 41. Bulldozing cleared areas north of US 41, 

first in the early sixties and later in association with a hog farm and nursery in the 

early seventies. Fires burned the area in 1962, 1971, 1974, and 1981. Hurricanes 

that affected the area in 1960 (Donna) and 1965 (Betsy) contributed to seed spread. 

Deer were held in a pen immediately west of SR 94 and south of US 41 sometime 

during the 1960's and disturbed the soil in the area. Farming of the prairies 

adjacent to US 41 also resulted in soil disturbance. 

Dense stands of melaleuca are found on spoil material immediately south of 

Monument Lake. Bulldozed and burned windrows northeast and northwest of the 

intersection of US 41 and the Loop Road (SR 94) also support developed stands. 

Surrounding these dense stands are scattered individuals in the muhly prairies and 

pinelands. Outliers are found up to 3 miles north of US 41 (Dayhoff pers. comm.) 

Dense stands are found just south of US 41 and west of SR 94. At least three age 

classes are seen in these areas and seem to correlate to the 1962, 1971 or 74, and 

1981 fires. Scattered individuals are found southwest of these dense stands for at 

least five miles. The melaleuca are, for the most part, restricted to the pinelands 

and prairies, and infrequently found in cypress domes and strands. 

South of US 41 and east of US 94, scattered large individuals are found as well as a 

few seedlings. Unsuccessful control attempts (1980) in an area south of US 41 

resulted in a dense, coppice-growth from surviving root systems and downed trees. 

Paolito Station Area. The areal extent of melaleuca in this area ranges from 

Fifty-Mile Bend to Trail Center along US 41 and southwest for 2 to 3 miles into the 

~oop Road area. The oldest trees ire at Paolito Station and form a very dense 
stand adjacent to an old gas station. This heavily colonized area has a history of 

disturbance by bulldozer. Severe fires in 1971 and 1974 appear to have resulted in 

melaleuca colonization into surrounding cypress prairie areas. The major direction 

of stand expansion is southwest (probably due to sheet flow and previous ORV use), 

but scattered individuals are also found northwest of US 41. 

Jetport Area. This area is made up of local stands from Fifty-Mile Bend west to 

Trail. Town. The stands at Trail Town and Midway are small (area-wise), dense 

stands that do not appear to be spreading into surrounding areas. A small (3-4 

acre) stand is south of Oseola Village, and originated in the early seventies. Many 

scattered trees are found up to 4 miles west and 1 mile east of the jetport road 

growing in cypress prairie vegetation. Myers (1 975) used this area as one of his 

study sites and found successful germination and consistent, but slow growth of 

introduced melaleuca seed and seedlings. Obviously, proper conditions for establishment and survival are present, and this area may be one of the most susceptible 

throughout the BICY. 

Loop Road Area. Two stands of melaleuca are in this area. The largest is located 

at the intersecton of Paces Dike and Loop Road. The original trees were planted 

near a camp in 1960. The camp burned in 1962 and subsequently spread into the 

surrounding area, mainly south, but also some short distance to the north. The 

second stand is inside the Loop Road and is, also, a result of intentional planting at 

a camp. Many seedlings are found at the second site. The native vegetation being 

displaced by both stands of melaleuca is a pine-prairie mosaic. 

Interior Pinelands Area. Some trees were planted around a few hunting camps in 

the Raccoon Point region of the interior pinelands. From these trees scattered 

individuals and small stands have developed; These stands are, at this time, mostly 

restricted to the pine-cypress ecotone. However, a stand (approximately 100 m ) 

of large trees is growing in a severely burned marsh just south of the end of the 

L-28 Tieback (Gunderson and Loope 1982~). 

Ochopee Area. Scattered large melaleuca are found south of US 41 from the fire 

station on the east to the Golden Lion Motel on the west. This area is also heavily 

colonized by schinus. All of this area has been severely disturbed. Canals were 

dug to drain the area for farming. Borrow pits were dug and the fill deposited on 

nearby areas for housing development. Surrounding areas were also cleared for 

farming. Dense schinus stands on these distrubed areas seem to be keeping 

melaleuca expansion in check. North of US 4 1 three or four dense stands occur. 

They do not appear to be invading the surrounding prairie, even though the prairie 

was farmed at one time. 

Turner River, Birdon and Wagon Wheels Road Areas. Melaleuca is found at 

homesites along these roads. Attempted control of the melaleuca at many of these 

sites has been done by NPS staff, but melaleuca at some of the sites have 

recovered by root sprout. 

Factors affecting establishment 

Establishment of a species is a function of the species seed production, germination, and seedling survival. Meskimen (1962), Myers (1973), and Woodall (1980a) 
have thoroughly investigated melaleuca capabilities for survival through these 

critical stages. A brief review of their work will follow to illustrate this species 

prodigous reproductive success. 

The amount of seed produced by melaleuca is truly awesome. The species can 

flower up to five times a year, with good seed crops produced every 2-5 years 

(Meskimen, 1962). The tiny seeds (30,000 seedslgram) are stored in small capsules 

along the branches. The seed capsules remain on the tree for as long as seven 

years (Meskimen 1962). Seed production can begin on an individual as young as 

3 years old. Meskimen (1962) estimated as many as two million seeds may be 

stored on a large individual. Alexander and Hofstetter (1975) calculated 20 million 

seeds may be found on a 10 m individual. Even with low viability measurements of 

20 to 30 percent (Meskimen 1962, Myers 1975, and Woodall 1980a) the potential 

regenerative capabilities of one individual tree is in the millions. 

The seeds are released from the capsule when the capsule dries out. The 

dessication is usually caused by a break in the xylem tissue leading to the capsule. 

Catastrophic+,events, such as frosts, fire, or mechanical disturbance, can initiate 

seed release. Old capsules may also dry out as part of an aging process. Droughts 

can also trigger release. Since melaleuca stores seed, and these processes can 

occur randomly, the-seed could be, theoretically, released any time of the year. 

Once the seed is released, it may move some distance away from the parent tree 

before it reaches the ground. Meskimen said the seed fell within 1.5 times the 

height of the tree. Browder and Schroeder (1980) used a mathematical model to 

predict aerial seed movement. Their work deter mined the longest probable 

distance a viable seed would travel to be I km. The maximum distance of 

movement, during hurricane force winds, would be 7 km. Woodall (1980a) validated 

their model for distances up to 65 m with good correlation. Their model seems 

fairly realistic, with the main points being that the seed are not infinitely mobile, 

and that areas now free of melaleuca are not likely t o b e subjected to seed rain. 

Other vectors, such as water, may contribute to seed movement, but as Woodall 

(1980a) points out, much resistance exists from native vegetation, and the tiny seed 

probably do not float for more than a couple of days. 

Animals, especially humans, are also effective dispersal agents. Any mammal, 

such as deer, opossum, or raccoon, can conceivably "catch" a melaleuca seed and 

carry it for miles. Humans are probably more active in transport. Seeds which fall 

on off-road vehicles (ORV1s) can be transported to most places in the preserve. 

Dayhoff (pers. comm.) feels, that the distribution of isolated melaleucas, 

southwest of Monroe Station, and north of Monument Lake, are a result of ORV's. 

He observed that the parking sites of vehicles was (and is) directly beneath the 

oldest, largest stand at Monroe Station. Most of the individuals to the south and 

north are adjacent to buggy trails and, probably, arrived via this means. 

Once the seed reach the ground, successful establishment is determined by the 

proper environmental conditions for germination. Two factors influencing the 

germination of melaleuca are soil characteristics and hydrologic pattern. 
Meskimen (1962) found that the dry, acid sands of the Bear Island Area were more 

conducive to germination than alkaline marls, and that generally, germination 

correlated well with soil pH. Soil characteristics though do not seriously' inhibit 

ermination, as abundant regeneration has been observed on many rnarl sites t Meskirnen 1962, Duever et al. 1979). Successful germination usually occurs on 

seasonally dry sites (no standing water), but after the seed has been wet, a result of 

rain or heavy dew. Seed that fall into standing water can germinate on dry ground 

if the water quickly recedes. Germination can occur under water, but only if the 

dissolved oxygen concentration is relatiavely high ( 4.0 ppm; Myers 1975). Therefore, germination does not occur on sites with very low soil moisture, nor sites with 

extended inundation, yet can occur on intermediate sites. 

It is currently unknown how long a melaleuca seed will remain viable once released 

from the tree. In Myers (1975) seeding trials, germination usually occurred within 

one month of seeding. Woodall (1980a) feels that the seed may last up to 2 years, 

and can definitely remain viable up to 10 months. 

The earliest stages of the seedling survival are perhaps the most critical to the 

survival and may be the largest determinants of the species distribution. Once the 

seed has germinated, its immediate fate is determined by many factors, including 

soil moisture, soil chemistry, soil physics, competition with existing vegetation, 

fires, and frosts. 

Melaleuca can survive a variety of soil moisture conditions once the seedling is 

developed to pertlaps the % to 1 meter height range. The new germinant can 

survive inundation for at least 3 months (Meskimen 1962, Sena Comes and 

Kozlowski 1980). Whereas Myers (1975) found survival after 6 months inundation, 

but mortality at less than 12 months. Growth of the terminal shoot was stopped 

while the seedling was inundated in all of these experiments. The seedling can also 

grow rapidly enough to maintain contact with receding soil water tables (Woodall 

1980a). However, Myers (1975) observed seedling mortality during the dry season, 

so the species does succumb to a lack of soil moisture. 

Woodall (1980a) discusses other factors of seedling survival, including soil temperature, nutrients, and soil pH. High temperatures, low nutrients, and high pH all can 

limit the growth and development of seedlings. These factors are not capable of 

being manipulated for management purposes. Also, melaleuca is already seen 

invading sites where a wide range of these conditions exist. 

Fire can and will kill young seedlings, yet the use of fire for management must be 

judicious. Fires will kill new germinants found in a litter layer by consuming both 

the litter and seedlings. It is unkown about the survival of young seedlings in a 

grass-fuel fire, such as the muhly prairie, but it is presumed they would die. Once 

the seedling is in the K to 1 m range, the survival is probably good. Seedlings with a 

basal diameter of 2-3 cm have been observed to resprout following a burn. 

Myers (1975, 1983) looked at growth rates on various communities in the BICY. 

Seedlings in disturbed sites such as drained cypress and burned cypress domes 

exhibited the greatest height increases. Dwarf cypress, muhly, and pine prairie 
sites showed slow, but consistent growth, with mean values for 15 months of 

growth being 40, lo, and 5 cm, respectively, for these undisturbed sites. No growth 

was measured in a native cypress-mixed swamp forest, as no seedlings survived at 

these sites due to extended inundation. 

Natural disturbances 

Fire: Melaleuca is surely one of the most fire adapted plant species in south 

Florida. The species can survive repeated fires and indeed thrives by fire. Seeds 

are released following a burn (Meskimen 1962) and dropped on the resultant fertile 

seed bed. The seed bed has readily available nutrients and little competing 

vegetation (Duever et al. 1979). The melaleuca bark is thin, papery and quite 

flammable. Volatile oils in the leaves also contribute to this species flammability. 

The fire does not damage the cambial layers because of many layers of bark, and 

only the dry outer bark is consumed while the central bark is too wet to burn. The 

bark also carries the fire up the tree, creating a crown fire, which is virtually 

unknown in south Florida (Myers 1975, Wade et al. 1980). After a fire, the burned rx> i individual usually has a charred stem and is defoliated. The species quickly 

refoliates, and produces epicormic sprouts. 

Fire patterns (a result of both natural and human ignitions) in the BICY are 

conducive to the expansion of melaleuca. Hunters and cattlemen have altered the \, timing and, perhaps, frequency of fires (Duever et al. 1979, Taylor and Doren 

1982). Burning is largely confined to the dry season as Taylor and Doren (1982) 

reported that 96 percent of all fires in the 1979-80 season occurred from October 

through May. Many fires are started in the fall just prior to hunting season and are 

relatively benign. March through May fires are the most severe, both in terms of 

size and impacts. Hunters and cattlemen usually don't burn in the peak of the dry 

season, but burn in the fall when water levels are high, and the fires are confined 

to the pinelands. As these user groups are interested in the fresh vegetation 

sprouts after a fire, they probably burn as frequently as sufficient fuel loadings 

exist. Arsonists are responsible for lighting the severe fires in the dry season. 

In the BICY, three vegetation types are regularly burned: pinelands, muhly prairie, 

and cypress prairie (Taylor and Rochefort 1981). These three vegetation types are 

being actively invaded by melaleuca, and except for disturbed areas (such as 

borrow mounds) account for all of the native vegetation types being invaded. Fire 

undoubtedly is a major factor in the expansion process, indeed, age classes (as 

evidenced by height) can be traced to recent fire history. The young age classes 

around older individuals in the prairies around Monroe Station seem to correspond 

with the occurrence of recent fires in this area. 

Hurricanes: Hurricanes or severe tropical storms may spread melaleuca seed, but 

seem to have variable effects on the tree. Meskimen (1962) observed melaleuca 

after Hurricane Donna in 1960. He relates that large trees rooted in sand were not 

toppled, but that trees in shallow soil (such as those in BICY) are readily downed. 

The high winds also break branches and may blow their stems for hundreds of 

meters. The species readily resprouts following branch breakage, so the hurricanes 

may help result in multistem morphology. Saplings and seedlings are apparently 

unaffected by high winds (Meskimen 1962). 
Frosts: Severe frosts may defoliate melaleuca, but they readily refoliate. The 

frost damaged tree may also release seed. Frosts definitely do not kill melaleuca, 

and even rarely affect it. The freezes of 1977, 1981, and 1982, were severe in 

terms of record low temperatures. No foliage damage was even noticed on 

melaleuca in BICY following these events (Duever, et al. 1979, Gunderson 1981). 

Water consumption by Melaleuca 

Many arguments have been made on the consumptive use of water by melaleuca. 

Many people think that the species actually has a greater evapotranspiration (ET) 

rate than native species and therefore will dry up a wetland area. A few studies 

have been made to answer this question and their results will be presented. 

Meador (1977) conducted a greenhouse study comparing water loss from potted 

cypress and melaleuca seedlings. He found that melaleuca transpired slightly less 

on a per-seedling basis and even less on a per-leaf-area basis, because the leaf area 

of melaleuca was approximately twice that of cypress. He stated however, the 

yearly transpiratiori of water by tnelaleuca may be larger because it is evergreen, 

whereas cypress is annually deciduous. 

Alexander et al. (1977) compared melaleuca and sawgrass transpiration from pots 

placed in field conditions. On a per-leaf-area basis, no difference in transpiration 

was measured, but they presumed leaf-area differences between sawgrass and 

melaleuca sites would result in more water transpired from the melaleuca areas. . Olmsted (1978) studied the stornatal resistance of melaleuca, and compared 

differences among leaf sides, leaf ages, leaves on different age trees, various 

species, and environmental factors. Her data indicate that melaleuca probably 

does not transpire more than native species. Much variability exists in the 

measurements from various types of leaves, and under various environmental 

conditions, so that meaningful comparisons among species are difficult. 

Woodall (1980b) reviewed methods of estimating water loss, as well as, reported on 

a few experiments on his own. He concluded that reliable evapotranspiration 

estimates for south Florida vegetation types (native and exotic) do not exist. He 

states, however, that the replacement of gramineous wetlands by melaleuca forests 

would probably result in increased water loss from the system. 

Schinus terebinthifolius 

Distribution 

Schinus, also called Brazilian pepper, Florida holly, or christmas berry, is perhaps 

the second-most widespread exotic tree in the BICY. The highest concentration of 

schinus stands is located in the Ochopee area (Duever et al. 1979, and enclosed 

map). The schinus stands in this area are found on former prairie, cypress, and 

pineland sites with histories of clearing and farming during the 1930ts, 401s, and 

50's. Alexander and Crook (1975) found schinus to be a component of a mixed 

hardwood association with native species; Persea borbonia, Magnolia virginiana, 

Acer rubrum, Ilex cassine, and Cornus foemina. This analysis agrees with the 

description of Duever et al. (197-0 added Salix caroliniana, Myrica cerifera, 
and Baccharis halimifolia to the list of native associates. Except for some roadside 

stands, most of the schinus in the Ochopee area occupy sites with native species, 

and do not form the characteristic monospecific stands found in other areas, such 

as "Hole-in-the-Donut" region of Everglades National Park (EVER). The significance of this association is that the native hardwoods are emergent from the 

schinus canopy and are present as seedlings and saplings. This indicates regeneration of native species and not succession towards a schinus-dominated, monospecific stand. Alexander and Crook (1975) state the Ochopee area is drained by 

canals put in for agriculture. Restoration of natural water flow to this area, as 

proposed by Rosendahl and Sikkema (1 98 I), may help native hardwoods outcompete 

schinus. 

Schinus is also found in single-tree-wide stands on the berms along Turner River, 

Birdon, Wagon Wheel, and Loop Roads. The trees are still restricted to this berm 

and are not spreading into the nearby Muhlenbergia prairies. 

Schinus is also a component in the upland hammocks. Duever et al. (1979) report 

schinus occurring in hammocks in the saline marshes and mangrove area in the 

southern area of the preserve which borders Everglades National Park. Usually the 

schinus is found where a camp or former camp exists. These areas were cleared 

and schinus invaded the opened areas. Disturbed hammocks in the Ochopee area 

also show signs of schinus invasion. Most of these hammocks are surrounded by 

undisturbed vegetation, usually cypress-mixed hardwood forest. Schinus occupies 

elevated sites adjacent to the Turner River (Gunderson et al. 1982). Other stands 

were found on edges of hammocks located in Deep Lake Strand (Gunderson and 

Loope 1982d). Schinus has not been found in undisturbed hammocks. Proximity of 

a seed source and degree of disturbance to a hammock probably determine the 

amount of schinus likely to invade pristine hammocks. 

Pinelands peripheral to the Ochopee area have schinus as an understory component 

(Gunderson et al. 1982). The nearby old-field stands probably served as seed source 

to these areas. Usually, a 5 year or greater absence of fire in pinelands allows 

schinus to become established (Loope and Dunevitz 198 I), and these pinelands 

probably have a similar history. Currently, frequent fires burn these areas (Duever 

et al. 1979) and topkill the schinus. Subsequent root-sprouting allows schinus to 

quickly recover and persist. 

Ewel et al. (1982) compared the susceptability of pineland sawgrass-glade and 

hammocks in EVER to schinus invasion by sowing seed and transplanting seedlings 

into these communities. Although some environmental conditions are different 

between EVER cornmunities and BICY communities, many of the factors important 

to schinus survival, such as light, competition, and hydrology are similar. They 

determined that pinelands were most susceptible, since seed germination as well as 

seedling survival and growth were highest on these sites. Both the sawgrass glade 

and hammock had less germination, seedling survival and growth, and appear to be 

more resistant to schinus establishment than pinelands. 

Factors affecting establishment 

Ewel et al. (1982) studied schinus phenology for 2 years in EVER. They found that 

flowering peaked in February and the seed ripened on the trees between December 
and February. Taylor (1981) correlated the fire patterns in BICY with schinus 

fruiting patterns to show that burning occurs the same time of year as schinus fruit 

are ripe. Perhaps this fire pattern [nay give schinus a competitive edge by having 

viable seed on freshly burned ground, at a time when few native shrubs are fruiting. 

Schinus seed dispersal is mainly by animals, especially raccoons, opossums, 

catbirds, and robins (Ewel et al. 1982). Germination is improved by dilute acid 

scarification, a process analagous to passing through the intestine of an animal 

(Ewel et al. 1982). Since these animals traverse many vegetation boundaries, 

schinus is likely to become established any place favorable conditions exist. This 

may be on a cypress knee, or fork in a cypress tree, or the middle of a hammock, 

but survival is usually limited at these sites. In addition t o t h e work by Ewel et al. 

(1982) on the resistance exerted by native communities to successful schinus 

germination and growth, other authors have documented aspects of inhibition 

exerted by native vegetation. For example, Dunevitz and Ewel (1980) found Myrica 

cerifera (wax myrtle) to be allelopathic to schinus, that is wax myrtle exudes a 

chemical that inhibits schinus growth. 

Natural disturbances 

Hurricanes: Little is known about the effect of hurricanes on schinus. Isolated 

individuals may be uprooted by the strong winds, but the degree of uprooting is 

probably related to the severity of the winds. The root systems are shallow and 

probably not tenacious. With the shrub s t a t u r e t h e species exhibit, it is probably no 

more susceptible to windthrow than other native species, such as pine or cypress. 

The danger with hurricanes is the denuding of native vegetation in hammocks or 

pinelands leaving the area open to schinus colonization. Hurricanes usually occur 

in late summer, allowing little time for recovery of the native vegetation on these 

denuded sites before schinus seed ripen. (This scenario is hypothetical, as no 

documentation could be found on these effects.) However, schinus is an aggressive 

colonizer, with prolific amounts of readily dispersed seed and rapid growth rates on 

open or disturbed sites. So it is conceivable that schinus could colonize areas 

denuded by hurricanes, especially given the current distribution and abundance of 

schinus seed . 

Fire: Fire may be an effective means of precluding schinus invasion, but becomes 

ineffective once a thicket developes. Loope and Dunevitz (1981) felt that fire 

exclusion is the important reason for schinus domination on many Miami-rock ridge 

pineland sites. They showed that a burn frequency of less than once every 5 years 

effectively excluded schinus establishment from pinelands in EVER, even though a 

nearby copious seed source exists. 

Once an established seedling is greater than 1 meter tall, a burned, top-killed plant 

can readily resprout (Ewe1 et al. 1982) and persist at a site. Further development 

without fire can result in a well-developed thicket. Once a thicket of schinus is 

formed, the sparse standing fuels and moist litter make the site not conducive to 

fire, so the site rarely burns and schinus is perpetuated (Wade et al. 1980). 

The current fire regime in BICY pinelands may be acting to exclude schinus. 

Although t h e t i m e of the year of fires coincides with schinus seed ripening, the fire 
frequency appears to be such that schinus establishment and growth are hindered. 

Frequent fires in the pinelands, muhly prairies, and cypress prairies may be helping 

to exclude schinus from these vegetation types. 

Just as frequent fires may exclude schinus, infrequent severe fires are conducive to 

its establishment (Wade et al. 1980). Severe fires, which kill overstory pines and 

hardwood shrubs, remove existing, native vegetation leaving the site susceptible to 

schinus establishment. 

Casuar ina sp. 

Distribution 

Casuarina is a genus of plants commonly called Australian Pines. At least eight 

species of the genus were introduced in Florida before 1924 (Morton 1980). Three 

of the species are prevalent in south Florida, but only two are common in the 

BICY. Duever et al. (1979) found C. glauca and C. cunnin hamiana in the preserve. 

Most of the species along US 41 fit ort ton's (1980 * description of C. glauca. 

Casuarina was planted along US 41 from Trail Center (Dade county line) to FortyMile Bend. Planting was done as a WPA project during the 1930's (Duever et al. 

1979). Most of the other stands within the preserve are a result of intentional 

planting near homesites. Only one place in the BICY does there appear to be direct 

seeding of casuarina. This spot is on the south side of US 41, in Section 8 (T54S, 

R35E). These trees were identified as C. glauca. Morton (1980) relates stray 

reports of cones on this species, but she believes they actually may be hybrids of 

- C. glauca and C. equisetifolia. Whatever the species, these trees do appear to have 

originated fromseed, unlike the remainder of the stands in the preserve where only 

vegetative regeneration from root sprouts is observed. 

Natural disturbances 

Severe Storms: As Morton (1980) points out, casuarina is extremely susceptible to 

windthrow, a result of severe storms. Old large limbs become brittle and are easily 

blown down by strong winds. The shallow, flattened root system gives little 

stability and allows entire trees to be readily uprooted by hurricanes. Morton 

(1980) related the dramatic ease of uprooting following the 1945 hurricane. The 

writer remembers casuarina as a commonly downed species after hurricane Donna 

(1960) blew through the Ft. Myers area. 

Fire: Casuarina will burn, but the species found in the preserve will readily 

resprout. C. equisetifolia will not resprout after a fire, but the C. glauca and 

C. cunnin hamiana will. The dense litter layer characteristic of casuarina stands -? will burn usually smoldering, rather than a roaring fire) under dry conditions and 

will topkill the standing trees, but root sprouts will rapidly recover the site (Wade 

et al. 1980). 

Other Woody Exotic Species 

Three other species of exotic trees were located within the BICY, but do not now 

appear to be actively colonizing surrounding areas. 
Rosewood, Dalbergia sissoo, was planted at a homesite (now an NPS maintained 

homesite) on Birdon Road. Seedlings and saplings were found growing on the filled 

area around the house. No expansion into surrounding areas was noticed, however, 

the potential for regeneration may be high. 

Java plum, Syziguim sp. A single stand of java plum is located on the Loop Road 

2 miles south of US 41. No regeneration was noticed at this site. However, this 

species has regenerated into natural areas in the Naples area. 

Bottlebrush, Callistemon sp., is naturalizing from intentional plantings at Trail 

Center and homesites near Burns Lake. Only limited regeneration has been noticed 

and now, no more than a dozen trees are found at either site. 

CONCLUSIONS 

A. Melaleuca quinquenervia 

I 

1. The current distribution of melaleuca populations is now largely 

restricted to roadside stands, but many isolated trees and small stands 

are located in the interior pinelands, especially in the eastern portion 

known as Raccoon Point. Most developed stands can be traced to 

intentional plantings, but have expanded copiously from these original 

points. 

. 2. During the last 20 years, melaleuca has colonized and displaced 

vegetation types of Muhlenbergia prairies, cypress prairies, and pinelands. Current site conditions and patterns of recurring fires and 

severe storms will result in continued expansion of existing melaleuca 

populations. ORV's may be conveying viable seed, thereby increasing 

t h e a r e a l e x t e n t of potential colonization. 

3. Areas of concern are presented. These areas have the largest populations, and from stand structure, are steadily expanding in size. 

B. Schinus terebinthifolius 

1. Schinus is generally restricted to the disturbed areas around Ochopee 

and should be expected to continue to dominate these areas. 

2. Roadside stands are found on elevated berms along Turner River, Wagon 

Wheel and Birdon Roads. These stands are restricted to the berms and 

show little sign of expanding into surrounding prairie and cypress prairie 

vegetation types. These two types appear fairly resistent to schinus 

invasion. 

3. Disturbed hammocks now support schinus stands. These stands will 

probably remain stable, unless a disturbance opens these areas to 

further colonization. 
4. Pinelands, especially near Ochopee, have a schinus component in the 

understory shrubs. Frequent fires probably help to maintain schinus in a 

low abundance in all pinelands. 

C. Casuarina spp. 

1. Casuarina is fairly restricted in its distribution in BICY. Most 

casuarina stands are a result of direct planting. Only one stand of 

casuarina appears to be expanding as a result of direct seeding. All 

other stands of casuarina in BICY are slowly expanding by vegetative 

regeneration. 

D. Other Species 

1. Rosewood (Dalbergia sissoo) is colo-nizing the immediate, artificial area 

around a NPS homesite on Birdon Road. 

2. Java plum (Syzigium sp.) Trees of this species are found in the 

preserve. It has not been observed to regenerate in the preserve, but 

has been found to seed in similar vegetation types nearby the preserve. 

3. Bottlebrush (Callistemon sp.) is naturalizing in some areas, but is very 

restricted in range. 

ACKNOWLEDGEMENTS 

Mr. Fred Dayhoff is gratefully acknowledged for providing much useful information 

based on personal experience and knowledge of this subject. R. Rochefort and 

I. Olmsted reviewed the paper, as did L. Mytinger. Last, but not least, Dee Childs 

and Jessie Brundige typed the various drafts of the manuscript. 
II~ ROAD 

AREAS WITH MELALEUCA (1071) 

MEAS WlTH BCHlNUS (1911) 

AREAS WlTH NO EXOTIC TREES (1971) 

Figure 1. Location of fifteen, 1 mi2 quadrats within Big Cypress National 

Preserve surveyed by Alexander and Crook (1975). No exotic plants 

were found in any quadrat during their review of the 1940 aerial 

photographs. Quadrats with exotic species present in 1971 are noted. 
IWmmHIb ROAD SURVEY 

7 VEGETATION YAP 

AERIAL PHOTOGRAPHS (107.) 

Figure 2. Areas surveyed by various methods to map distribution of woody exotic 

species in Big Cypress National Preserve. c 
Turner River Road 

Dense Concentrations 

a Sparse Concentrations 

Figure 3. Current (1982) distribution of Melaleuca in Big Cypress National 

Preserve. Dense concentrations indicate dense, well-developed stands. 

Sparse concentrations indicate outliers or individuals. 
LITERATURE CITED 

Alexander, T. R., and A. G. Crook. 1975. Recent and long-term vegetation 

changes and patterns in South Florida: Part 11. Final Report, South Florida 

Ecological Study. 827 p. 

Alexander, T. R., and R. H. Hofstetter. 1975. Some eclogical aspects of 

Melaleuca quinquenervia (Cav.) Blake in southern Florida. Presentation 39th 

FAS meeting. Lakeland, Fla. 

Alexander, T. R., R. H. Hofstetter, and F. Parsons. 1977. Comparison of transpiration of cajeput and sawgrass. Presentation 41st FAS meeting, 

Gainesville, Fla. 

Arvinitis, L. G. 1978. Distribution mapping of Melaleuca in south Florida via 

remote sensing. Final Report. U. S. Forest Service, Southeast Forest Expt. 

Sta., Asheville, N.C. 113 p. 

Austin, D. F. 1978. Exotic plants and their effects in southeastern Florida. Env. 

Cons. 5(1): 25-34. 

Black, D., and S. Black. 1980. Plants of Big Cypress National Preserve: a 

preliminary checklist of vascular plants. National Park Service, South 

Florida Research Center Report T-587, Homestead, Fla. 

Browder, J. A., and P. B. Schroeder. 1980. Melaleuca seed dispersal and 

perspectives on control. Proc. Melaleuca Symposium, Fla. Div. Forestry. 

Capehart, B. L., J. Ewel, B. Sedlik, R. Myers, J. Browder, and H. T. Odum. 1977. 

Remote sensing survey of spread of Melaleuca. Photogrammetric Eng. and 

Remote Sensing 43: 197-206. 

Cost, N. D., and G. C. Craver. 1980. ~istribution of Melaleuca in south Florida 

measured from the air. Proc. Melaleuca Symposium, Fla. Div. of Forestry. 

Davis, J. H., Jr. 1943. The natural features of south Florida, especially the 

Everglades. Fla. Geol. Surv. Bull. 25. 31 1 p. 

Duever, M. J., J. E. Carlson, J. F. Meeder, L. C. Duever, L. H. Gunderson, L. A. 

Riopelle, T. R. Alexander, R. F. Myers, and D. P. Spangler. 1979. Resources 

Inventory and Analysis of the Big Cypress National Preserve. Center for 

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Schinus terebinthifolius. Fla. Scient. 44: 1-13. 

Ewel, J., R. Meador, R. Myers, L. Conde, and B. Sedlik. 1976. Studies of Vegetation change in south Florida. Report to U. S. Forest Service, Botany Dept., 

Univ. of Fla., Gainesville. 119 p. 
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Successional Ecosystems of Ever glades National Park. National Park Service, 

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Gunderson, L. 1981. Effects of freeze on plant species in Big Cypress National 

Preserve. Memo to Supt., on file Everglades National Park. 1 p. 

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Turner River Area, Big Cypress National Preserve. National Park Service, 

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Gunderson, L. H., W. R. Maynard, and L. L. Loope. 1980b. Vegetation Map of 

Pinecrest Area, Big Cypress National Preserve. National Park Service, South 

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Research Center, Homestead, Fla. 

Gunderson, L. H., and J. VanHorn. 1981b. Vegetation Map of Deep Lake Strand 

Area. Big Cypress National Preserve. National Park Service, South Florida 

Research Center, Homestead, Fla. 

Gunderson, L. H., L. L. Loope, and W. R. Maynard. 1982. An Inventory of the 

Plant Communities of the Turner River Area, Big Cypress National Preserve. 

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Homestead, Fla. 53 p. 

Gunderson, L. H., and L. L. Loope. 1982a. An Inventory of the Plant Communities 

in the Pincrest Area, Big Cypress National Preserve. National Park Service, 

South Florida Research Center Report T-655, Homestead, Fla. 43 p. 

Gunderson, L. H., and L. L. Loope. 1982b. An Inventory of the Plant Communities 

in the Levee-28 Area, Big Cypress National Preserve. National Park Service, 

South Florida Research Center Report T-664, Homestead, Fla. 29 p. 

Gunderson, L. H., and L. L. Loope. 1982c. An Inventory of the Plant Communities 

in the Raccoon Point Area, Big Cypress National Preserve. National Park 

Service, South Florida Research Center Report T-665, Homestead, Fla. 36 p. 

Gunderson, L. H., and L. L. Loope. 1982d. An Inventory of the Plant Communities 

in the Deep Lake Strand Area, Big Cypress National Preserve. National Park 

Service, South Florida Research Center Report T-666, Homestead, Fla. 39 p. 

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Miami Geo. Soc. Mem. 2. 

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Press, Coral Gables, Fla. 962 p. 
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Florida. National Park Service, South Florida Research Center Report 

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Melaleuca quinquenervia in sothwest FlorKda. M. S. Thesis, Univ. of Florida, 

Gainesville. 15 1 p. 

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quinquenervia in southern Florida. 3. Appl. Ecology 20:645-658. 

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422 p. 

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Collier County, Florida. Unpubl. report on file, Everglades National Park, 

Homestead, Fla. 20 p. 

Olmsted, I. C. 1978. Stomatail resistence and water stress in Melaleuca. Final 

contract report, USDA Forest Service, Lehigh Acres, Fla. 36 p. 

Rosendahl, P. C., and D. A. Sikkema. 1981. Water Management Plan: Turner River 

Restoration. National Park Service, South Florida Research Center Report 

M-621, Homestead, Fla. 

Sena Gomes, A. R., and T. Kozlowski. 1980. Responses of Melaleuca guinquenervia seedlings to flooding. Physiol. Plant. 49: 373-377. 

Sturrock, D. 1968. Trees for southern Florida. Central and Southern Florida Flood 

Control District, West Palm Beach, Fla. 242 p. 

Sweet, H. C. 1981. Use of an Apple computer to identify vegetation and assess 

coverage within single LANDSAT pixels. p. 695-701 in Proc. 7th Int. Symp. 

on Machine Processing of Remotely Sensed Data. Purdue, Univ., West 

Lafayette, Ind. 

Taylor, D. L., and R. F. Doren. 1982. Summary of Fires in Everglades National 

Park and Big Cypress National Preserve, 1980. National Park Service, South 

Florida Research Center Report T-663, Homestead, Fla. 
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National Preserve. 

Wade, D. D. 1980. Some Melaleuca-fire relationships, including recommendations 

for homesite protection. Proc. Melaleuca Symp. Fla. Div. of Forestry. 

Wade, D. D., J. J. Ewel, and R. H. Hofstetter. 1980. Fire in South Florida 

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Woodall, S. L. 1980a. Site requirements for Melaleuca seedling establishment. 

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Fla. Div. of Forestry. 
SCALE 

---EXTENT OF STAND OUTLIERS 

M-Molalouca qulnquenervla 

S-Schlnus tereblnthlfollus 

C-Casuarlna spp. 

I DISTI-3TION OF WOODY EXOTIC PLANTS 1 

BIG CYPRESS 

NATIONAL PRESERVE 

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OTHER EXOTICS LOCATED BY NONSYSTEMATIC FIELD SURVEYS AND AERIAL RECONNAISS NCE t