Trees: High Pollen levels between 91 and 1,500 will likely cause symptoms for many individuals who suffer from allergies to the predominant pollen types of the season.

Grass: Moderate Pollen levels between 6 and 20 tend to start affecting individuals extremely sensitive to the predominant pollen.

Weeds: Low Pollen levels between 0 and 10 tend to affect very few individuals among the allergy-suffering public.