Plant · GBIF taxon 8002952
common ragweed
Ambrosia artemisiifoliaAlso known as Annual Ragweed, Low Ragweed, Bitterweed, Roman Wormwood
Common ragweed is an adaptable annual herb notorious for producing massive quantities of lightweight windborne pollen that triggers seasonal allergies across millions of people. Its deeply dissected, fern-like leaves emerge in spring, giving rise to tall green stems topped with subtle spikelike clusters of tiny yellowish flowers by late summer. A single mature plant can release over one billion pollen grains into the air, making it a powerful driver of late-season hay fever.
AllergenWind-PollinatedAnnual Plant
—observations
—countries
—peak records
Least ConcernConservation statusIUCN Red List categoriesLCNTVUENCREWEXLeast ConcernRed List categories, explained →
Diet & prey
- Autotrophic (Photosynthesis)
Predators
- Ragweed Leaf Beetle
- American Goldfinch
- Dark-Eyed Junco
ThreatsHerbicides and active weed control measures in agricultural regions
HabitatsDisturbed soil, roadsides, agricultural fields, pastures, urban lots
Life spanAnnual (1 year)
Size / weightNot available
Classification
- OrderAsterales
- FamilyAsteraceae
- GenusAmbrosia
- SpeciesAmbrosia artemisiifolia
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Pollen is a severe hay fever trigger; sensitive individuals should avoid dense stands in late summer.
- Why it is dangerous
- Produces large volumes of microscopic windborne pollen that induce severe allergic rhinitis, asthma flare-ups, and conjunctivitis.
- How to recognize a risky encounter
- Look for fern-like leaves paired with tall, yellowish-green terminal spikes of tiny male flower heads in late summer.
- What to do
- Avoid physical contact during peak blooming season, and do not shake or disturb flowering stems.
Responsible observation
- Identify Early: Look for lacy, feathery green leaves with hairless or sparsely hairy surfaces before flower spikes form.
- Minimize Bloom Exposure: Stay indoors on warm, windy mornings from August to October when airborne pollen counts peak.
- Manage Safely: Wear a dust mask and protective gloves if removing plants manually prior to flowering.
Look-Alike no rights reserved, uploaded by Adam Kranz · cc0
Competitor 
Close Relative (c) Douglas Goldman, some rights reserved (CC BY-SA), uploaded by Douglas Goldman · cc-by-sa
Close Relative (c) Annabell Hormann / korina.info, some rights reserved (CC BY-SA) · cc-by-sa
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