Weeds

Thistle, Bull

Thistle, Bull
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Bull thistle is a spreading annual or biennial herbaceous plant that invades almost any type of disturbed area throughout the United States. The weed forms dense thickets and displaces other vegetation. Spiny, spreading, winged stems grow up to 7 feet tall. Leaves are 3-12 inches long, spear-shaped, and very hairy. Flowers develop at the apex of the plant from June to September. The purple flower heads are 1-2 inches long with narrow, spine-tipped bracts.