science

Ah yes, the Gympie Gympie tree. It is truly horrible.

It is the most horrible tree in the world, people have been known to commit suicide the sting is so bad.

Not only that but it stings for months or years and the trichromes stay in the skin and release the toxin whenever triggering events happen, such as touching the affected skin, contact with water, or temperature changes.

For two or three days the pain was almost unbearable; I couldn't work or sleep... I remember it feeling like there were giant hands trying to squash my chest... then it was pretty bad pain for another fortnight or so. The stinging persisted for two years and recurred every time I had a cold shower...There's nothing to rival it; it's ten times worse than anything else.

https://en.m.wikipedia.org/wiki/Dendrocnide_moroides