The idyllic beaches of the Caribbean are a dream destination for people from all over the world. Who wouldn’t want to enjoy a peaceful and rejuvenating vacation, lying on white sands, listening to the murmur of crystal-clear waters breaking against the shore while savoring a piña colada?
It certainly sounds like a dream getaway. However, such a trip could quickly turn into a real nightmare if you have the misfortune of encountering the world’s most dangerous tree according to the Guinness World Records: the manchineel tree or “manzanillo de la muerte” (manchineel of death) as it was named by Spanish conquistadors.
The Swedish naturalist Carl von Linnaeus called it Hippomane mancinella. The first term of the binomial name means ‘horse madness.’ It seems that Linnaeus might have been inspired by the name coined by the Greek philosopher Theophrastus to refer to a plant native to Greece that drove horses mad when they consumed it.
Distribution and characteristics
Its natural distribution area includes the sandy coastal regions between South Florida and Venezuela, Mesoamerica, several Caribbean islands, Peru, and the Galapagos Islands. It also grows in mangroves.
These are large evergreen trees, reaching heights of up to 50 feet. The bark is grayish. They have wide, globular crowns. Their leaves are simple, alternate, elliptical, leathery, and have long petioles. The fruit resembles a small and appetizing yellow or greenish apple, hence its common name.
It is a member of the Euphorbiaceae family, to which castor oil plants and the famous spurges (Euphorbia sp.) also belong. These plants are known for the milky, whitish sap that oozes from their stems when cut: latex. This substance can cause irritation when it comes into contact with mucous membranes, giving us clues about its biological function. Latex is one of the various defense mechanisms that plants have to deter herbivores, similar to the stinging hairs of the stinging tree (Dendrocnide moroides), which we discussed in a previous article.
Dendrocnide moroides. The plant that causes excruciating pain
An extremely caustic substance
The latex of this species is particularly caustic and irritating. Nearly all parts of the tree can secrete this substance when broken: leaves, fruits, branches, and bark. It can cause severe burns, inflammation, and blisters if it comes into contact with the skin. If it enters the eyes, besides causing excruciating discomfort, it can lead to serious damage to eye tissues and temporary or permanent blindness. The fumes produced by burning its timber are also irritating to the eyes and mucous membranes. While the chemical composition of this milky sap is complex, diterpene esters are suspected to be the primary culprits of these effects.
The fruit is especially dangerous due to its succulent appearance and fruity aroma, which may tempt someone to take a bite. However, this imprudence can lead to a distressing agony often accompanied by abdominal and oropharyngeal pain, diarrhea, and vomiting. Severe cases may result in pharyngeal edema requiring tracheotomy, coma, or death. Furthermore, since the symptoms take several minutes to manifest and fruits are small, it is common for affected individuals to consume several apples before experiencing any warning signs, which can worsen the diagnosis. To make matters worse, the pollen of this species is highly allergenic.
Diterpene esters in the latex are water-soluble, so it is not advisable to take shelter under this tree to protect yourself from the rain since the drops that run down the leaves and branches of the tree may carry diluted latex. It is also not recommended to park your vehicle in the shade of this tree. Its latex is so corrosive that it can even erode the paint on the car’s body.
Without a doubt, Hippomane mancinella has a very effective defense mechanism against herbivores. It repels the vast majority, except for the black iguana (Ctenosaura similis), which can live in the branches of the manchineel tree and consume its fruits, showing an astonishing immunity against the caustic latex.
Applications and uses
Despite its danger, this species has not managed to keep humans away, who have been using its wood for furniture making for centuries. However, this involves a prior sun-drying of the timber to neutralize the latex’s causticity. The Caribs used to dip the tips of their arrows in latex for hunting. Even a legend claims that Juan Ponce de León, the discoverer of Florida, died after being wounded by an arrow poisoned with manchineel latex. On the other hand, the resin has been recorded for use in Jamaica for the treatment of venereal diseases and dropsy, while the fruits, once properly dried, have been used as a diuretic remedy.
Traumatic testimonies
As early as the 16th century, when inhabitants of the Old World began establishing their colonies in the New World, accidents related to the manchineel tree were already being recorded. For example, the chronicler of the Indies Peter Martyr reported in his De orbe novo that even the shade of this tree affects the head and injures the eyes.
In the 17th century, the English writer Richard Ligon documented a preventive practice among workers who were engaged in felling manchineel trees: they covered their eyes with a cloth to prevent latex from falling on them. Otherwise, they could go blind for a month. This is precisely what happened to the carpenters of the HMS Herald in the following century when they felled the trees without any protective measures, as described by naturalist Berthold Seemann.
Admiral Horatio Nelson also experienced the harmful effects of the manchineel firsthand. In 1779, while leading a British expedition to Spanish Nicaragua, he was poisoned after drinking water from a spring that local Indians deliberately saturated with manchineel leaves.
Hundreds of people have had the misfortune of suffering the consequences of encountering the manchineel tree up to the present day. In fact, local authorities have been forced to mark these trees with warning signs or red paint to keep curious individuals away and prevent the list of victims from growing.
So, now you know, if you’re planning a dream vacation in the Caribbean, take the time to familiarize yourself with the local flora beforehand to avoid having your trip ruined by the irritating effects of Hippomane mancinella.
REFERENCES
Adolf W, Hecker E (1984). On the active principles of the spurge family, X. 1,2skin irritants, cocarcinogens, and cryptic cocarcinogens from the latex of the manchineel tree. J. Nat. Prod. 47, 482-496. https://doi.org/10.1021/np50033a015
Andreu MG, Friedman MH (2023). Hippomane mancinella, manchineel. Ask IFAS, University of Florida [online]. Available in: https://edis.ifas.ufl.edu/publication/FR370
Bourcard-Maitre D, Cachet X, Bouzidi C, Riffault-Valois L, Dupuy C, Garnier R, Langrand J (2019). Severity of manchineel fruit (Hippomane mancinella) poisoning: A retrospective case series of 97 patients from French Poison Control Centers. Toxicon 161, 28-32. https://doi.org/10.1016/j.toxicon.2019.02.014
Guinness World Record (2011). Most dangerous tree: Manchineel (Hippomane mancinella) [online]. Available in: http://www.guinnessworldrecords.com/world-records/most- dangerous-tree-/
Hippomane mancinella L. in GBIF Secretariat. GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed through GBIF.org on 2023-11-01.
Pitts JF, Barker NH, Gibbons DC, Jay JL (1993). Manchineel keratoconjunctivitis. Br. J. Ophthalmol. 77, 284-288. https://doi.org/10.1136%2Fbjo.77.5.284
