Cocklebur
Xanthium strumarium
- Plant type
- forb (annual)
- Settings
- Disturbed ground, Riparian and wet ground
- Risk
- Moderate risk Our rating from the cited sources.
- Review
- Not yet reviewed by a veterinarian.
Photos
Planned.
How to tell it
Coarse annual; the bur is covered with spines and has two beaks (Merck).
Look-alikes: Planned.
What to do on a site walk
- Avoid units with fresh seedlings.
Why it matters
- Toxic principle
- Carboxyatractyloside
- Toxic parts
- Seedlings (two-leaf stage) and seeds
- Basis for our rating
- Chewgrass rating. Cornell and ARS report poisoning mostly in pigs and cattle; Langston lists cocklebur among plants that harm goat livers.
Signs in goats
Depression, weakness, staggering, spasms, death (ARS, Merck).
If you think an animal has been poisoned, call your vet right away.
Season
Seedlings at the two-leaf stage are most toxic, often on drying flood ground and pond edges (ARS, Merck).
Sources
Links last checked: 2026-10-31