Species PlantsGiant Ragweed

Giant Ragweed

Ambrosia trifida

CommonPlant
Illustration of Giant Ragweed (Ambrosia trifida)
Safety note: Can cause allergic reactions in sensitive individuals.

Giant Ragweed is a robust plant that can grow over 10 feet tall. It has large, lobed leaves and produces significant amounts of pollen, contributing to seasonal allergies.

Habitat
Found in fields, along riverbanks, and in disturbed areas.
Diet
Primarily wind-pollinated, affecting those with allergies.
How common
Common

Best time to see a Giant Ragweed

The best time to see a Giant Ragweed is June–September, when about 61% of U.S. sightings happen, based on 45,310 research-grade iNaturalist observations.

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