Propolis, often termed "bee glue," is a remarkable natural substance with a long history beyond the hive. It is a complex resinous mixture that honeybees produce by combining gathered plant resins and saps — primarily from tree buds like poplar and conifer — with their own enzymes and beeswax. This sticky, antimicrobial compound is used to seal cracks, sterilize the hive interior, and mummify intruders, acting as the colony's chemical immune system. The name itself comes from the Greek, roughly meaning "before the city" — a reference to its role as a protective barrier at the hive's entrance. In this way, propolis fulfills a protective role within the hive not unlike that of resin in certain trees.

The ancient Egyptians already used propolis in embalming, and Greek and Roman physicians, including Aristotle, described its use in wound treatment. Beekeepers today mostly harvest propolis using special screens that the bees seal with the resin, without harming the colony in the process. Modern research into its antimicrobial and antioxidant properties has confirmed many of these long-standing traditional uses. In Slavic and Georgian folk medicine, too, propolis has traditionally been worked into wound-healing salves, and in South America, stingless bees (Meliponini) produce their own, chemically distinct variety of propolis valued for similar properties. Today propolis increasingly appears in cosmetic and skincare products as well, while food safety authorities regularly monitor the quality of commercial propolis supplements.

The scent of burning propolis is profound, complex, and evocative. Its primary character is richly resinous, balsamic, and woody, with a foundational note reminiscent of poplar buds, storax, and warm honey. Upon heating, it releases a smoky, slightly pungent quality, layered with subtle hints of vanilla, cinnamon, and a faint medicinal sharpness. For burning, it is best to use a charcoal disc or an electric incense warmer; only a small piece is needed, as the fragrance is potent. Because of its intensity, propolis works particularly well as a small, accent ingredient within more complex incense blends. Beginners are advised to start with a cautious amount and work their way up gradually to the fragrance's full intensity. Propolis thus remains a powerful, concentrated special case among incense materials. Once experienced, its intense fragrance is not easily forgotten.