Natural Products From The Beehive Dietary Supplement Kosher What is Bee Propolis? In preparing to write this article, it became apparent that the subject of propolis is as complex as the substance itself. To appreciate propolis, in modern day terms, one must realize what propolis meant to ancient cultures. To understand the significance of propolis to man, one must first understand its significance to bees. And to understand what propolis means to bees, one must understand what its raw material, tree resin, means to trees. Finally, to decipher what propolis means to science, and how propolis fits into the framework of biological science and the eco-system, we must first understand, fundamentally, the process and the goals of scientific research.