Pollen is formed in the pollen sacs in the anthers, which are a part of the stamens in the plant, and they are known as the structures that carry the male gamete to the female gamete. The term "Pollen Cloud" is used for pollen flying in the air and "Pollen Rain" for pollen falling on the ground. The capture of pollen by the female organs (stigma) of plants is called "Pollination" or "Pollination". They vary greatly in terms of shape, color and content, and are generally ellipsoid. After the pollen matures in the anthers, it is released and scattered around. With this event called dissemination, the pollen flies on the ground, on water surfaces or among tree branches and leaves for a while.

 

Wind-pollinated plants produce large amounts of pollen to ensure fertilization. For example; Pinus spp. In (Pine) a male cone can produce around 5 million pollen per year, and the tree itself can produce nearly 12.5 billion pollen, and they can fly up to 300 km in strong winds. Fagus spp. While the number of pollen produced by a flower cluster in (Beech) is 12 thousand, this amount goes up to 2 billion in a single tree. Again, one flower cluster of Juglans regia (Walnut) can produce around 2 million pollen, and one flower cluster of Corylus spp. can produce around 5 million pollen.

 

Today, in studies aimed at detecting pollen in the air, pollen capture devices such as "Lanzoni and Burkard" are mostly used according to the volumetric method. This device makes it possible to determine the hourly, daily, weekly and monthly changes in pollen in m3 of air. Pollen calendars made for any region are a guide in protecting individuals sensitive to allergic pollens against allergens. In Izmir, which was chosen as the pilot region, it is of great importance for people sensitive to pollen to announce to the public the beginning of the periods when pollen is scattered into the atmosphere, the periods when it reaches the highest density and the periods when it ends, together with the meteorological parameters.