Common cocklebur

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.

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

 

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

 

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

 

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