Eucalyptus: “By 1868, the Tre Fontane Abbey near Rome was almost abandoned. The soil was depleted, the surrounding community deserted, and worst of all, malaria had reached an intolerable level. At that time people still believed that malaria was caused not by mosquitoes carrying a parasite but by something in the air; the word itself meant “bad air” in Latin. The monks hit upon an unusual solution to their problems: they planted stands of eucalyptus trees around the monastery. This fast growing Australian Tree, which, after all, smelled of medicine, would surely clear the air, rid the abbey of malaria, improve the soil, and give the monks some sort of crop with which to earn an income. They even made a tea which they believed would keep malaria away.”
Excerpt from The Drunken Botanist written by Amy Stewart.