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Stem shape is uniform from the ground to the crown.
Leaf bases, also known as boots, tend to slough off the tree as they dry, giving
the trunk a smooth appearance (Duncan and Duncan 1988; Walker 1990). Leaves are
palmate with no spines, and may measure 3 m (9.8 feet) in length, each with a
prominent midrib. Flowers are cream colored and droop in clusters from the
crown. Fruits are black and fleshy with a single seed (Olson et al. 1974). They
may measure 8 mm (1/3 inch) in width. Root systems are short and bulbous,
penetrating the soil to depths of 4.6 – 6.1 m (15-20 feet).
II. HABITAT AND
DISTRIBUTION
Regional Occurrence:
Sabal palmetto occurs from southernmost
portions of North Carolina through Florida and the Florida Keys to Cuba and the
Bahamas. It is widely cultivated in the Hawaiian Islands (St. John 1973).
IRL Distribution:
Cabbage palms occur throughout the Indian River
Lagoon, most commonly in communities characteristic of barrier islands and beach
dunes: live oak-sea oats communities, sand pine scrub, and palmetto prairies
(Alexander 1955).
III. LIFE HISTORY AND POPULATION BIOLOGY
Age, Size, Lifespan:
S. palmetto grows to a height of 10 – 25 m
(32-82 feet), with a stem diameter of approximately 30 – 60 cm (12-24 inches).
Leaves may measure up to 3 m (9.8 feet) in length. Fruits are small, measuring
approximately 8 mm (1/3 inch) in width. Root systems are deeply penetrating, and
may reach depths of 4.6 – 6.1 m (15-20 feet) (Duncan and Duncan 1988).
Abundance:
S. palmetto is abundant throughout the
Florida and the Indian River Lagoon system.
Locomotion:
Sessile.
Reproduction:
S. palmetto flowers from April through
August, depending upon latitude. S. palmetto is insect pollinated. Fruit
develops throughout the fall, and ripens in winter (St. John 1973; Olson and
Barnes 1974; Wade and Langdon 1990). Birds and small mammals that eat the fruit
of this tree aid in seed dispersal.
Embryology:
Seeds are buoyant and salt resistant, requiring no
pretreatment in order to break dormancy. Germination is hastened by planting
seeds in moist sand at 3 ° C (38°
F) for 30 days. Optimum planting depth is 1.5 – 3 cm (0.5 – 1 inch) in light
soil. Seed survival is reported to be low due to consumption by animals. Wade
and Langdon (1990) reported that as little as 9% of 620,000 seeds produced per
acre survived frugivory.
First year growth consists of the primary root, one
fully expanded leaf, and a rhizomatous stem (Wade and Langdon 1990).
IV. PHYSICAL TOLERANCES
Salinity:
Sabal palmetto is highly tolerant of salt
spray, and inundation by brackish water. Seeds of this species are also salt
resistant (Wade and Langdon 1990).
Physical Tolerances:
St. John (1973) listed Sabal palmetto as one
of the most insect resistant trees in southern Florida. Cabbage palms are also
highly resistant to infection by pathogens (Wade and Langdon 1990).
V. COMMUNITY ECOLOGY
Trophic Mode:
Autotrophic.
Competitors:
Probable competitors include exotic species such as
Australian pine (Casuarina spp.), melaleuca (Melaleuca quinquenervia),
coconut palm (Cocos nucifera) and Brazilian pepper (Schinus
terebinthifolia).
Habitats:
Optimum growth occurs in humid subtropical to warm
temperate climates where average rainfall is 100 – 163 cm (39-64 inches), and
average maximum/minimum temperatures range from –4 - 36°
C (25-97 ° F). Northern growth is limited by low
winter temperatures.
Preferred soil type for S. palmetto is calcium
rich, and neutral to alkaline in nature. Cabbage palms prefer poorly drained
soils, and often grow at the edge of freshwater and brackish wetlands. This
species tolerates flooding (Alexander 1955).
Associated Species:
Due to the diversity of its habitats, S.
palmetto also has a variety of associates. Overstory plants include slash
pine (Pinus elliotii), pond pine (P. serotina), loblolly pine (P.
taeda), longleaf pine (P. palustris), and various oaks (Quercus
spp.). Understory plants include gallberry (Ilex glabra), saw
palmetto (Serenoa repens), greenbriar (Smilax spp.), bracken ferns
(Pteridium spp.), bluestems (Andropogon spp.), sawgrass (Cladium
jamaicensis), beak rush (Rhynchospora spp.), and others.
Black bear, raccoons, bats, wild turkeys, white-tailed
deer, gulls, cardinals, grackles, blue jays, and scrub jays all rely on the
fruit of S. palmetto for food (St. John 1973; Olson and Barnes 1974; Wade
and Langdon 1990).
VI. SPECIAL STATUS
Special Status:
None.
Benefit in IRL:
S. palmetto is not only a popular ornamental
plant throughout its range, it also provides food for many birds and mammals of
the Indian River Lagoon, including the threatened scrub jay.
Economic Importance:
S. palmetto is widely cultivated in Hawaii.
Its commercial uses include wharf pilings, poles, table tops, and broom handles
(Walker 1990; Wade and Langdon 1990).
VII. REFERENCES
Alexander, T.R. 1955. Observations on the ecology of
the low hammocks of
southern Florida. Journal of the Florida Academy
of Sciences. 18(1): 21-27.
Austin, D.F., F.R. Posin, J.N. Burch. 1987. Scrub
species patterns on the Atlantic
coastal ridge, Florida. Journal of Coastal
Research. 3(4):491-198.
Duncan, W.H. and M.B. Duncan. 1988. Trees of the
southeastern United States.
University of Georgia Press. Athens, GA. 322 pp.
Monk, C.D. 1966. An ecological study of hardwood swamps
in north-central
Florida. Ecology. 40(1):1-9.
Oosting, H.J. 1954. Ecological processes and vegetation
of the maritime strand in
the southeastern United States. Botanical Review.
20:226-262.
Olson, D.F., R.L. Barnes, Jr. 1974. Sabal palmetto.
In: Schopmeyer, C.S., ed.
Seeds of woody plants in the United States.
Agriculture Handbook No. 450.
U.S. Department of Agriculture, Forest Service,
Washington, D.C. pp.
744-745.
St. John, H. 1973. List and summary of the flowering
plants in the Hawaiian
Islands. Cathay Press Limited, Hong Kong. 519 pp.
Wade, D.D. and Langdon, O.G. 1990. Sabal palmetto
(Walt.) Lodd. ex J.A.
and J.H. Schult. Cabbage palmetto. In: Burns, R.M.,
B.H. Honkala, technical
coordinators. Silvics of North America. Vol. 2.
Hardwoods. Agric. Handb.
654. U.S. Department of Agriculture, Forest
Service,Washington, D.C. pp.
762-767.
Walker, L.C. 1990. Forests: A naturalists guide to
trees and forest ecology. Wiley
nature editions. John Wiley and Sons, Inc. New
York, NY. 288 pp.
Wunderlin, R.P. 1982. Guide to the vascular plants of
central Florida. University of
South Florida, University Presses of Florida,
Tampa, FL. 472 pp.
Report by: K. Hill, Smithsonian Marine Station
Submit additional information, photos or comments to:
irl_webmaster@si.edu
Page last updated: Oct. 19, 2001
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