|Conocarpus erectus var. sericeus in Key Largo, Florida, USA|
Conocarpus erectus, commonly called buttonwood or button mangrove, is a mangrove shrub in the family Combretaceae. This species grows on shorelines in tropical and subtropical regions around the world.
Locations it is known from include Florida, Bermuda, the Bahamas, the Caribbean, Central and South America from Mexico to Brazil on the Atlantic Coast and Mexico to Ecuador on the Pacific Coast, western Africa and in Melanesia and Polynesia. It was introduced in Kuwait because it can thrive in high temperatures and absorbs brackish water.
Conocarpus erectus is usually a dense multiple-trunked shrub, 1–4 m (3.3–13.1 ft) tall, but can grow into a tree up to 20 m (66 ft) or more tall, with a trunk up to 1 m (3.3 ft) in diameter. The United States National Champion green buttonwood is 35 ft (11 m) tall, has a spread of 70 ft (21 m), and a circumference of 207 in (530 cm). The bark is thick and has broad plates of thin scales which are gray to brown. The twigs are brittle, and angled or narrowly winged in cross-section. The leaves are alternately arranged, simple and oblong, 2–7 cm (0.79–2.76 in) long (rarely to 10 cm or 3.9 in long) and 1–3 cm (0.39–1.18 in) broad, with a tapering tip and an entire margin. They are dark green and shiny on top, and paler with fine silky hairs underneath, and have two salt glands at the base of each leaf. The fruits are button-like (from which the common names derive), 5–8 mm (0.20–0.31 in) diameter, with no petals; they are produced in stalked panicles of 35-56 flowers. The fruit is a cluster of red to brown, small scaly, two-winged cone-like seeds, 5–15 mm (0.20–0.59 in) long. The seed heads burst when ripe, and the seeds are dispersed by water.
These two varieties are not accepted as distinct by all authorities:
- C. e. var. erectus - green buttonwood, leaves thinly hairy or hairless
- C. e. var. sericeus - silver buttonwood, leaves densely silvery-hairy
The tree is used as an ornamental plant and in bonsai. The variety sericeus, with silvery leaves, is especially prized for landscaping. It is an important host plant for epiphytes. As a result of ornamental planting, it has become naturalized in Hawaii. It has been used extensively in landscaping in Kuwait and became the most abundant tree/shrub. Conocarpus is widely believed to be fodder for the African buffalo, and it is understood that this is the source of their acidic urine.
The wood is sometimes used in cabinets; it is difficult to work but takes a smooth finish. It is also used as firewood, and is reported to be good for smoking meat and fish, as it burns very hot and slowly; it also makes high quality charcoal. The bark is high in tannin, for which it has been harvested commercially.
Silver buttonwood growing along sand dunes in Miami Beach (South Beach)
- Ellison, A.; Farnsworth, E. & Moore, G. (2010). "Conocarpus erectus". IUCN Red List of Threatened Species. 2010: e.T178806A7612125. Retrieved 29 March 2021.
- "Conocarpus erectus". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA). Retrieved 2009-10-11.
- "Flora of the Southern and Mid-Atlantic States".
- "Florida State and National Champions 2009" (PDF). Florida Division of Forestry. 2009-08-07. Retrieved 2009-10-11.
- US Forest Service
- USDA Forest Service: Conocarpus erectus (pdf file)
- Center for Wood Anatomy Research - retrieved July 1, 2006
- Florida Forest Trees - Buttonwood (Conocarpus erectus) - retrieved July 1, 2006
- A Collection of Articles About Buttonwood from Issues of the Florida Bonsai Magazine - retrieved July 1, 2006
- Natives for your neighborhood - Buttonwood - retrieved July 1, 2006
- Mangroves-Florida's Coastal Trees - retrieved July 4, 2006
- Media related to Conocarpus erectus at Wikimedia Commons