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 S. H. Brown Silver buttonwood, Fort Myers, Florida, early June Silver buttonwood, Punta Gorda, Florida, early June S. H. Brown Formal hedge, late September Leaves in formal hedge S. H. Brown 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. S. H. Brown 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.