The manchineel grows on Caribbean and South Florida beaches and looks like the best shade there — glossy leaves, dense canopy, small green fruit.
Every part carries a milky sap. On skin it behaves like a caustic burn: redness, then blisters that can take days to settle.
Which is why sheltering under it in rain is the trap. Runoff carries diluted sap onto bare shoulders. Nothing has to be touched.
In the BMJ in 2000, radiologist Nicola Strickland described tasting a beach apple on Tobago, then a burning tightness that made swallowing difficult for hours. She recovered.
In Florida and Curacao the trunks are painted with red bands. People paint warnings because the tree gives none.