Juniper / Cedar

severe allergen

Juniperus

tree pollen

Mountain cedar (Juniperus ashei) and other junipers are notorious allergens, especially in Texas and the southwest. 'Cedar fever' is a well-known phenomenon in central Texas where mountain cedar pollen causes intense allergic reactions in winter. These trees release massive amounts of pollen — visible as clouds of 'smoke' rising from the trees on dry, windy days.

Grain Size

20-30 micrometres

Prevalence

Dominant in Texas Hill Country, the southwest, and parts of the west. Mountain cedar is the primary culprit in Texas. Eastern red cedar (J. virginiana) is common in the east.

Allergy Severity

severe

Bloom Period

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Bloom Peak

Cross-Reactivity

If you're allergic to juniper / cedar pollen, you may also react to:

Cypress (strong cross-reactivity)
Japanese cedar (Cryptomeria)
Other Cupressaceae family trees

Practical Tips

'Cedar fever' in Texas peaks December-February. Despite the name, it's an allergic reaction, not an infection.
Cedar pollen can trigger asthma attacks in sensitive individuals.
The visible 'smoke' from juniper trees on windy days is pure pollen — avoid being downwind.
Cedar allergies often develop after moving to Texas, even in people with no prior allergy history.