Toxicological trivia from october 29, 2009: Citronella is the common name of lemongrass, a grass that can reach over five feet tall, straight blades, wide and hollow, known worldwide as lemongrass by its characteristic odor. It is considered originating from:
a) Asia;
b) Central;
c) Africa.

Answer a. It is of Asian origin (India, Thailand, Vietnam, China). Read more in Spanish monograph: Repellents. Information Update 2009