This method is used for the more woody herbs/roots. Important to use a stainless steel or an enamel saucepan. The herb material is covered with cool water, brought to the boil then simmered ON THE STOVE for 15 to 60 minutes depending on the type of material. Usually 1 part herb to 5 parts water. Decoctions are mainly for external use. Ointments and creams are decoctions using oils, wax or fats instead of a water base.