Buttonwood (Conocarpus erectus)

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Stephen H. Brown, Horticulture Agent
Joy Hazell, Sea Grant Agent
Kim Cooprider, Master Gardener
Lee County Extension, Fort Myers, Florida
(239) 533-7513 brownsh@ufl.edu
http://lee.ifas.ufl.edu/hort/GardenHome.shtml
Conocarpus erectus
Family: Combretaceae
Buttonwood; Green Buttonwood;
Silver Buttonwood
Silver buttonwood and globose cone-like
fruit.
Synonyms (Discarded Names): Conocarpus erectus
var. arboreus; C. procumbens; C. erectus var.
procumbens; C. erectus var. sericeus; C. sericeus;
C. supinus; Terminalia erecta
Origin: Coastal swamps in much of Florida;
the Caribbean to South America
U.S.D.A. Zone: USDA 10a-11 (Minimum 30°F)
Growth Rate: Medium
Flowering Months: Year round
Leaf Persistence: Evergreen
Salt Tolerance: High
Drought Tolerance: High; can tolerate occasional to
frequent wet soils
Soil Requirements: Wide range
Nutritional Requirements: Low
Potential Pests: Sucking insects
Typical Dimensions: 30’- 40’ x 20’- 30’
Propagation: Cuttings, seed
Human hazards: None known
Uses: Hedges; specimen plant; oceanfront landscapes;
shoreline plantings; highway medians
S. H. Brown
Mature green buttonwood landscape trees.
Natural Geographic Distribution
Buttonwood is native to Bermuda, both coasts of south Florida, the Bahamas, the Caribbean (except
Dominica) Mexico, Central and South America and the Galapagos Islands. Sometimes called “button
mangrove”, the plant usually grows just inland from the white mangroves. While this is the norm, green
buttonwood can be found growing on beaches as pictured below. It also is commonly found in a wide
variety of inland habitats such as the edges of low hammocks and the borders of fresh and brackish
marshes. Buttonwood is in the same family as the white mangrove, tropical almond and black olive.
Conocarpus erectus is also found on the other side of the Atlantic along the coast of Africa. The buttonwood in African is thought to have landed there by means of floating fruits.
S. H. Brown
On the front line, Bunche Beach, Town of Fort Myers Beach, Florida, early November.
Joy Hazell
Tree in natural habitat, Pine Island, Florida, early June
Ecological and Ethnobotanical Functions
Buttonwood is a seaside shrub or tree with highly salt-resistant foliage. It protects the soil during storm
surges and helps stabilize dunes. Buttonwood provides food and cover for wildlife. It is a favorite fuel
for smoking fish and makes an excellent firewood emitting very little smoke while burning. It has also
been used as a source for charcoal. The wood is heavy and durable in water, making it useful for boats,
barges and other maritime construction. Although very durable, the wood is susceptible to attack by dry
-wood termites. The bark has been used in tanning and in medicine and the leaves also contain tannin.
Buttonwood has been used as an astringent and as a folk remedy for many ailments.
Green and Silver Buttonwoods
Two main types of buttonwoods are recognized. They are primarily distinguished by the appearance of
their leaves. Conocarpus erectus is the green buttonwood. The yellow green, glabrous (hairless) leaves
are leathery and slightly fleshy. Conocarpus erectus var. sericeus is the silver buttonwood and is
naturally occurring. Its leaves are densely covered with silky or silvery hair giving the tree a silver color.
Its color is not genetically fixed. It is used extensively in home landscapes and is reputedly less cold
tolerant than the green leaved buttonwood. ‘Momba’ is a smaller cultivar with a dense crown. Another
cultivar, ‘Card Sound’, has long, narrow leaves, similar to Podocarpus macrophyllus.
S. H. Brown
Conocarpus erectus
S. H. Brown
Conocarpus erectus var. sericea
Boynton Botanicals
Boynton Botanicals
Conocarpus erectus ‘Card Sound’
Conocarpus erectus ‘Momba’
Morphology and Growth Habit
Button is often mistaken for a mangrove. In fact, buttonwood and mangroves are closely associated in
the coastal environment. Buttonwood differs from mangrove in reproduction strategy. Buttonwood
reproduces using seeds. A true mangrove is viviparous, meaning it reproduces using propagules which
are live trees that develop on the parent tree. Buttonwood is a low-branching evergreen shrub or tree
with a typical height of 35 feet. It is an erect tree with a spreading, irregular branched crown. The bark
is dark brown, ridged and scaly. When continually exposed to wind, the trunk takes on a distinctive
gnarled and twisted shape. The wood is hard and without growth rings. The twigs are yellow green
when young, becoming brown with age. The buttonwood has alternate, entire leaves; the short petioles,
1/8 to 3/8 inches long, have 2 dot-like glands and are slightly winged. The leaf blade is elliptic to oval
or lanceolate and the apex obtuse or acuminate. The leaf is usually 1-1/4 inches to 4 inches long and 1/2
to 1-1/4 inches wide. Flowers are inconspicuous, with clusters of white flowers mostly 1 to 3 inches
long. They appear at the end of twigs and at leaf axils. The flowers are usually unisexual; males and
females with some bisexuals. There are no petals, and the sepals are fused and greenish white. Male
flowers lack the tubular base (hypanthium) and pistil and have longer stamens. Buttonwoods flower and
fruit throughout the year. The brownish red fruit look like old leather buttons, giving the plant its common name. The dry, individual fruits (drupes) are 2-winged, overlapping and separating at maturity.
S. H. Brown
Alternate leaf arrangement
The short petioles have a pair of glands
S. H. Brown
Inflorescence, Fort Myers, Florida, late May
Twig demarcation; yellow
green when young becoming
brown with age.
Reproduction
Buttonwood seed heads may contain from 35-56 fruits each, with an apparent low rate of viability. It is
very rarely established by self-sown seedlings. Buttonwoods can also be propagated by partially
burying large branches in moist ground as living fence posts.
Planting and Maintenance Guidelines
Buttonwood is a tough long-lived plant that grows well in sandy or rocky, alkaline soils as well as wet,
saline conditions. It is well suited for difficult urban situations and is highly recommended for seaside
plantings. It is available as a single or multi-trunk specimen. Plant it in full sun or partial shade but it is
not tolerant of dense shade. It requires no irrigation except in the driest sites. Buttonwood is a “clean”
tree and is not associated with distinct seasonal leaf loss. Its medium textured dense foliage makes it
ideal for use as a clipped hedge of varying heights or as a tall screen. For screen, set plants about 5 feet
apart. The rough, scaly bark makes an ideal environment for the attachment of bromeliads and orchids.
S. H. Brown
Old green buttonwood on Bokeelia with the Gulf of Mexico in the
background, late November.
Old trunk of tree to the left
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Silver buttonwood, Fort Myers, Florida, early
June
Silver buttonwood, Punta Gorda, Florida, early June
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Formal hedge, late September
Leaves in formal hedge
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Informal green buttonwood hedge
Landscape Problems
Buttonwood has a few insect pests including the Florida wax scale that sucks sap from the plant. Sooty
mold, caused by the secretion of sucking insects, rarely accumulates on the plant. Leaves of the silver
buttonwood are often discolored by a dark material of unknown origin. This hardly seem to have
affected its landscape popularity. The Sri Lanka weevils chew and eat the leaves and causes foliage
damage. An unknown twig distortion was discovered on Sanibel in green buttonwood in October of
2008. The condition was not attributed to disease or insect.
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Condition of unknown origin common to silver
buttonwood
Nymphs of Florida wax scales, Cercoplastes
floridensis, on leaf
Lyle Buss
S. H. Brown
A rare leaf distortion found on green buttonwood.
Sanibel, Florida, October
Adult wax scales
References
Tomlinson, P.B. The Biology of Trees Native to Tropical Florida. 1986. Harvard University Printing
Office.
Workman, Richard W. Growing Native. 1980. The Sanibel-Captiva Conservation Foundation, Inc.,
Sanibel, FL 33957
Little, Elbert L., Jr and Wadsworth, Frank H. Common Trees of Puerto Rico and the Virgin Islands.
1964. U.S. Department of Agriculture; Forest Service. Washington, D.C. 20250
Francis, John K. Button Mangrove. U.S. Dept. of Agriculture, Forest Service, International Institute of
Tropical Forestry. http://www.fs.fed.us/global/iitf/pdf/shrubs/Conocarpus%20erectus.pdf
Click here for Library of Native Plant Fact Sheets.
This fact sheet was reviewed by Jenny Evans, Sanibel-Captiva Conservation Foundation; Peggy Cruz,
Lee County Extension Service; John Sibley, Lee County Master Gardener and owner of All Native
Garden Center, Nursery & Landscapes, Fort Myers.
The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research,
educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, religion, age, disability, sex, sexual orientation, martial status, national origin, political opinions or affiliations.
U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A. & M. 6/2011.
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