Made from the natural exudation of trees and plants, gums and resins are the way such plant life protects itself from injury whether animal or atmospherically caused; the resultant sap drying and forming a hard shell to cover and seal the wound.
Such gums and resins are often highly aromatic as well as having medicinal attributes and have been collected and used for thousands of years as an incense or for treating minor ailments as well as for cleansing and spiritual reasons.
Botanical incense is usually the dried leaves, heartwood, bark and stems of highly aromatic woods and leaves, which, when burnt, release their aroma in the resultant smoke.