Iris Cohen schreef
Sounds like something similar to the legends of the Upas tree, Antiaris
toxicaria, which is native to the South Pacific & possibly southeast Asia.

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Actually the species occurs in Africa too. There were seventeen species
described in the genus which were reduced to first four, then one species.
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The sap is poisonous & was used on blow-darts. The legend about it being
deadly to sleep under may have arisen because the tree was common near an
active volcano that gave out poisonous fumes.
There is an equally or more poisonous tree native to Florida and the
Caribbean, the manchineel, Hippomane mancinella. People are warned not to
sit under it, because dripping sap can cause a severe rash. The two trees
are not related.
Iris,

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The Euphorbiaceae s.l. (to which Hippomane belongs) contain some more
species with a reputation for being poisonous, with names such as
blind-my-eyes. Don't forget about Anacardiaceae.
PvR