It is a viscous acidic substance that is soluble with ether and turpentine. Honey bees collect honey from buds, tree sap, or other sources.It is a resinous resinous substance (balsamic) waxy, mixed with a proportion of pollen and bee saliva, sticky in color ranging from dark brown and reddish to greenish black, with a bitter taste, which is made by bees from several external and internal sources.One of the most important external sources of the resin and plant resin gums that it collects from outside, especially from the viscous material covering the buds(Petals) tree branches and bark of forest tree trunks such as poplar, sidr and carob, which protect the plant from the vagaries of the weather, in addition to protecting it from the attack of germs (and other viruses, fungi and bacteria) on it, and these advantages benefit bees to form propolis by mixing it with their saliva and adding pollen to it ( 5-10%), wax (20-30%), and a little honey to make propolis.And bees use it to adhere tires and strengthen the wax disks and fill cracks in the hive and narrow entrances in the winter.Propolis is used to close small incisions about 6 millimeters (0.24 inch or less), while large incisions are usually closed with beeswax. Its color depends on its source, most of it is dark brown.Propolis is sticky at room temperature or 20 ° C (68 ° F) above, and becomes hard and brittle at cooler temperatures.The bees also use it to cover some of their enemies that kill them inside the hive, and their size is large and difficult to remove from the hive, such as large butterflies, lizards and mice, and in this way they prevent their decomposition and rot.The bees need propolis, but if the amount that bees collect from it increases, it is considered one of the defects of the breed, as this leads to sticking the disks together and blocking the lanes, causing the bees to confuse and hinder their work, and hinder the work of the beekeeper during the examination in addition to contaminating the tires and wax with this substance and the Caucasian bee breed is considered the most of the breeds A collection of this article.