Xanthium strumarium

Wildflowers

Dicots

Eudicots

Asterids

Asterales

Asteraceae

Heliantheae

Ambrosiinae

Xanthium

Cocklebur.

Found on Jesusita trail inside the stream crossing near Cator between Cator and Steven’s park. Its congener, clotspur, above the creek. The two may be distinguished by their leaves — the leaves of this plant are fatter and shorter than those of clotspur.

I noticed it blooming between August and September 2011 (probably starts earlier, but I didn’t notice).

flowers above, seeds (burs) below

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