Manchineel

The manchineel tree (Hippomane mancinella) is a species of flowering plant in the spurge family (Euphorbiaceae). Its native range stretches from tropical southern North America to northern South America.
The name manchineel (sometimes spelled manchioneel or manchineal), as well as the specific epithet mancinella, are from Spanish manzanilla ('little apple'), from the superficial resemblance of its fruit and leaves to those of an apple tree. It is also called beach apple.
A present-day Spanish name is manzanilla de la muerte, 'little apple of death'. This refers to the fact that manchineel is one of the most toxic trees in the world: it has milky-white sap that contains numerous toxins and can cause blistering. The sap is present in every part of the tree—bark, leaves, and fruit.
Hippomane mancinella grows up to 15 metres (49 feet) tall. It has reddish-grayish bark, small greenish-yellow flowers, and shiny green leaves. The leaves are simple, alternate, very finely serrated or toothed, and 5–10 centimetres (2–4 inches) long.
Spikes of small greenish flowers are followed by fruits, which are similar in appearance to an apple, are green or greenish-yellow when ripe. The fruit is poisonous, as is every other part of the tree.
Manchineel is native to the Caribbean, the U.S. state of Florida, the Bahamas, Mexico, Central America, and northern South America.
The manchineel tree can be found on coastal beaches and in brackish swamps, where it grows among mangroves. It provides excellent natural windbreaks and its roots stabilize the sand, thus reducing beach erosion.
The manchineel tree is listed as an endangered species in Florida.
All parts of the tree contain strong toxins. Its milky white sap contains phorbol and other skin irritants, producing strong allergic contact dermatitis.
Standing beneath the tree during rain will cause blistering of the skin from mere contact with this liquid: even a small drop of rain with the sap in it will cause the skin to blister. Burning the tree may cause ocular injuries if the smoke reaches the eyes. Contact with its milky sap (latex) produces bullous dermatitis, acute keratoconjunctivitis and possibly large corneal epithelial defects.
Although the fruit is potentially fatal if eaten, no such occurrences have been reported in the modern literature. Ingestion can produce severe gastroenteritis with bleeding, shock, and bacterial superinfection, as well as the potential for airway compromise due to edema.
When ingested, the fruit is reportedly "pleasantly sweet" at first, with a subsequent "strange peppery feeling ... gradually progress[ing] to a burning, tearing sensation and tightness of the throat." Symptoms continue to worsen until the patient can "barely swallow solid food because of the excruciating pain and the feeling of a huge obstructing pharyngeal lump."
In some parts of its range, many trees carry a warning sign – for example on Curaçao – while others are marked with a red "X" on the trunk to indicate danger. In the French Antilles the trees are often marked with a painted red band roughly 1 metre (3 ft) above the ground.
Although the plant is toxic to many birds and other animals, the black-spined iguana (Ctenosaura similis) is known to eat the fruit and even live among the limbs of the tree.
The tree contains 12-deoxy-5-hydroxyphorbol-6-gamma-7-alpha-oxide, Furocoumarins, sapogenines, hippomanins, mancinellin and other phorbol esters, which are responsible for the manchineel's toxicity.
A poultice of arrowroot (Maranta arundinacea) was used by the Arawak and Taíno as an antidote against such poisons. The Caribs were known to poison the water supply of their enemies with the leaves. Spanish explorer Juan Ponce de León died shortly after an injury incurred in battle with the Calusa in Florida—being struck by an arrow that had been poisoned with manchineel sap.
Despite the inherent dangers associated with handling it, the tree has been used as a source of wood by Caribbean furniture makers for centuries. It must be cut and left in the sun to dry the sap. To avoid dangerous contact with the poisonous parts, the tree may be burnt at the base to fell it.