All the great Asian medical traditions embrace herbal medicine, using a wide variety of plant species. Medicines might originate from any part of a plant, be it the flowers, stems, leaves, fruits, roots or bark.
Harvesters pay particular attention to the places where plants grow, the time they are harvested and their method of processing. In addition, some traditions include animal products, metals, minerals and precious gems in their remedies.
Plants and other ingredients are classified primarily by the five tastes (sweet, sour, bitter, pungent and salty) of the Chinese medical tradition and by the six tastes (sweet, sour, salty, bitter, pungent/hot and astringent) of Ayurveda and the Tibetan medical tradition. These further correspond with the five elements - earth, metal, water, wood and fire (Chinese system) and earth, fire, water, air and space in the Indian and Tibetan traditions. Also taken into consideration are the properties (hot/cold, heavy/light, smooth/rough and dull/sharp).