An herbal tea, tisane, or ptisan is an herbal infusion not made from the leaves of the tea bush (Camellia sinensis). (Varieties of "real" tea include black, oolong, green, yellow, and white tea.) Tisanes can be made with fresh or dried flowers, leaves, seeds or roots, generally by pouring boiling water over the plant parts and letting them steep for a few minutes. Seeds and roots can also be boiled on a stove. The tisane is then strained, sweetened if so desired, and served. Most know herbal teas are naturally non-caffeinated.