Zubrowka, or bison-grass (Hierochloe odorata L.) - sweet grass from the primeval Bialowieza Forest. Hierochloe odorata contains coumarin, used to flavor Polish Zubrowka Vodka.
Hierochloe, from the Greek, hieros - "sacred", and chloe - "grass"; odorata, from the Latin: "sweet smelling, fragrant; ill smelling". Other common names include: Buffalo Grass, Holy Grass, Vanilla Grass, Feur Moire (Gaelic).
What a smell! Delicious!