How are pollen counts done?

Collect, microscope. Pollen counting involves collecting the pollens and molds on specialized rods, or in special traps. These counters measure a set volume of air over a period of time. The rods are stained and examined under a microscope. Pollens have different characteristics that allow experts to label them as grasses, trees or weeds. Mold spores tend to stain differently and can also be identified.