Differentiating between tree, grass, and weed pollen.
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Plants that rely on the wind to distribute their pollen are the primary culprits for allergies. Their pollen is lightweight, buoyant, and produced in massive quantities. Brightly colored flowers pollinated by insects rarely cause allergies.
| Pollen Type | Peak Season |
|---|---|
| Tree Pollen | Early Spring (March - May) |
| Grass Pollen | Late Spring/Summer (May - July) |
| Weed Pollen (Ragweed) | Late Summer/Fall (August - First Frost) |
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Sampson HA, et al. "Second symposium on the definition and management of anaphylaxis: Summary report" — Journal of Allergy and Clinical Immunology.
View sourceAmerican College of Allergy, Asthma & Immunology (ACAAI) "Allergy Facts and Figures" — ACAAI Clinical Resources.
View sourceWorld Allergy Organization (WAO) "White Book on Allergy — 2025 Update" — World Allergy Organization.
View sourceNational Institute of Allergy and Infectious Diseases (NIAID) "Clinical Guidelines for the Diagnosis and Management of Food Allergy" — National Institutes of Health.
View sourceMuraro A, et al. "EAACI food allergy and anaphylaxis guidelines: Diagnosis and management of food allergy" — Allergy — European Journal of Allergy and Clinical Immunology.
This content reflects clinical guidelines current as of the last review date shown above. Always consult a qualified healthcare provider for personalized medical advice.