Found in:

• Prairie and landscape plantings, and lawns (occasionally)

Characteristics:

• Biennial plant that produces a basal rosette and long taproot the first year
• Upright flowering stem grows 2-4’ tall the second year
• Stem is large, heavily branched and covered with dense hairs
• Leaves are coarsely lobed with a long, sharp spine on each tip
• Upper leaf surface is covered with stiff hairs and spines; lower surface is covered with dense, woolly, gray hair
• Compact reddish purple flower heads, 1-2” in diameter, bloom June through Aug
• Root system has a long taproot and underground stems (rhizomes)

Significance:

• Minnesota Primary Noxious Weed that spreads rapidly and aggressively from the extensive root and rhizome system and by seed

Plants that look similar:

• Canada Thistle
• Musk Thistle
• Plumeless Thistle
• Common Burdock (flower)

More information and control options for Bull Thistle...