Propolis Propolis Propolis or bee glue is a resinous mixture that honey bees produce by mixing saliva and beeswax with exudate gathered from tree buds, sap flows, or other botanical sources. It is used as a sealant for unwanted open spaces in the hive. Propolis is used for small gaps (approximately or less), while larger spaces are usually filled with beeswax. Its color varies depending on its botanical source, with dark brown as the most common. Propolis is sticky at and above , while at lower temperatures, it becomes hard and brittle. While foraging, worker bees primarily harvest pollen and nectar,
Animal glue earth and hoof glue. It would also be used to bind feathers and equipment together. The first commercial glue factory opened in Holland circa 1700, manufacturing animal glue from hides. The United States’ first glue factory opened in 1899, established by the Milwaukee Tanning Industry. The L.D. Davis company thrived producing animal glue during the Great Depression after shifting its focus from stenciling, selling to local box makers and other users; L.D. Davis' animal glue formula for bookbinding remains in production. During the 18th and 19th centuries, ranchers disposed of old animals – horses in particular – to glue factories.