Hierochloe odorata or Anthoxanthum nitens, also known as sweet grass, buffalo grass, bison grass, holy grass (UK), manna grass, Mary’s grass, seneca grass, sweetgrass, or vanilla grass, is an aromatic herb which grows in northern Eurasia and in North America. It is used in herbal medicine and in the production of distilled beverages (e.g., Żubrówka, Wisent). It owes its distinctive sweet vanilla scent and taste to the presence of coumarin. Very hardy perennial. Native to North America as well as Europe. Leaves do not have rigid stems, so only grow to about 20 cm (7.9 in) in height, and then leaves grow outward horizontally to 100 cm (39 in) long or more, by late summer. Bases of leaves, just below soil surface are broad and white, without hairs, underside of leaves are shiny, without hairs.
Sweet grass was, and is, very widely used by North American indigenous peoples. As a sacred plant, it is used in peace and healing rituals. Leaves are dried and made into braids and burned as vanilla-scented incense; long leaves of sterile shoots are used by Native Americans in making baskets. Natives of the Great Plains believe it was the first plant to cover Mother Earth. The Anishinaabe, Cree, Mi'kmaq, and other Algonquian first nations of Canada believe it is a purifier, and burn sweetgrass before all ceremonies. It is a reminder to respect the earth and all things it provides. It is also used in ceremonial items by the Blackfoot and Lakota peoples. Incense used by at least the Blackfoot, Cheyenne, Dakota, Kiowa, Lakota, Menominee, Montana, Ojibwa, Omaha, Pawnee, Ponca, Sioux, and Winnebago peoples. Used for purification, as oblations to ancestors, for protection of spirits, and keeping out of evil and harm. Used in a variety of ceremonies including peace ceremonies and initiations. Used by Blackfoot, Cheyenne, Kiowa, Lakota, Montana, Okanagan-Colville, Omaha, and Thompson for cosmetic and aromatic purposes. Blackfoot and Gros Ventre use leaves soaked in water and used it as a hairwash. Sweet grass tea and smoke were used for coughs and sore throats (Flathead, Blackfoot). Teas used as a wash to treat chapping and windburn, and as an eyewash. Used as body & hair decoration/perfume by Blackfoot, Flathead, and Thompson Indians. The Blackfoot chewed grass as a means of extended endurance in ceremonies involving prolonged fasting. Iroquois, Kiowa, Malecite, Menominee, and Mi'kmaq people (amongst others) use sweetgrass in basketry (including mats) and crafts. Kiowa use fragrant leaves as stuffing for pillows and mattresses. Used for sewing at least by Menominee. Used as an incense to "keep the bugs away" by Flathead. Used by Cheyenne to paint pipes in the Sun Dance and the Sacred Arrow ceremonies. Sweetgrass has a mellow, almost soporific effect, and for many is a useful aid to entering a meditative state. Coumarin, although not known to possess psychotropic effects, is common to a number of herbs used ritually which have strong anecdotal evidence for at least mild psychotropic properties.