Common cocklebur

Encyclopedia Article

Common cocklebur               Xanthium strumarium L.

Family:  Asteraceae (Composite family)
Life cycle:  Annual
Native status: Native
Habitat:   Crop fields, flood plains, disturbed areas

General description:  Erect plant reaching heights of 6 to 7 ft.  Stems are rough with dark spots.  Leaves are rough, triangular in shape with wavy or toothed margins and long petioles.  Inconspicuous flowers produce egg-shaped burs with two beaks at end. Seedling has long, fleshy cotyledons.

Key ID traits:  Rough stems with dark spots, triangular leaves with irregular margins.

Similar species:    Sunflower seedlings may resemble those of cocklebur, but sunflower has small, ovate cotyledons.

Miscellaneous:  Each bur contains two seeds, one possessing a deeper dormancy than the other.  Seedlings are highly toxic, but toxicity relatively quickly.

Cotyledons are strap-shaped and fleshy, first leaves are lanceolate in shape.


The dark spots on cocklebur stems are a key ID trait.


Juvenile cocklebur plant with many branches and triangular, rough leaves with shallow lobes.


Cocklebur seedling with bur attached.  The bur normally remains underground when a seedling emerges, but occasionally it gets stuck on the cotyledons.