The Fever tree is completely harmless but they have the early pioneers to blame for their ominous sounding name.
The pioneers believed that Fever trees were the cause of malaria outbreaks. It was eventually proved that Fever trees had absolutely nothing to do with malaria. The only thing the wrongfully accused Fever trees share with the real malaria culprits, the female Anopheles mosquitoes, is a love of swampy areas.
Nevertheless the story goes that locals would lie down in the shade of the tree to escape the burning sun. Invariably, they would fall asleep and would wake up covered in mosquito bites which would often lead to the onset of malaria.