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11 allergy-inducing pollen producers

By: Russell McLendon on April 21, 2011, 7:30 a.m.
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Juniper

This tree often looks like it's on fire — but it's just releasing pollen. Often called "mountain cedar," it's actually an Ashe juniper, one of many allergenic juniper species. Others include the Eastern red cedar, Pinchot's juniper and Western juniper.

Habitat: Usually semi-arid regions

Description: Small evergreen trees or shrubs with many stems. Most are dioecious, meaning only males produce pollen.

Allergenicity: Moderate to severe

Allergy season: Varies (e.g., winter for Ashe junipers; spring for Western junipers)

Tips: Avoid male junipers, especially near true cedars, since juniper and cedar pollen can cross-react. Also limit outdoor activity from 5 to 10 a.m. during juniper-allergy season, since that's typically prime time for pollen.