Species guide
Common ragweed
HarmlessAmbrosia artemisiifolia
How to recognise it
Up to about 1 m, with soft, deeply divided fern-like green leaves and inconspicuous green flower spikes at the stem tips.
Is it dangerous?
Not toxic to touch, but a leading cause of hay fever — its wind-blown pollen triggers seasonal allergies for millions.
What to do
Pull or cut it before it flowers to reduce pollen; manage allergy symptoms during late summer.
Recorded 189,061 times in the wild worldwide.
Think you've spotted one?
Photograph it and let SpecieSense confirm the species — and show you the reasoning.
Identify a specimen