Sounds like something similar to the legends of the Upas tree, Antiaris
toxicaria, which is native to the South Pacific & possibly southeast Asia. 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,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)