Scotch Thistle

SCOTCH THISTLE
(Onopordum acanthium L.)

GROWTH HABIT: Biennial, sometimes annual, erect, up to 8 ft. Tall. Rosette formed first year, flowering stem elongates second year.

LEAVES: Large, coarsely lobed, hairy on both sides, velvety gray appearance. Margins lined with sharp conspicuous spines, Basal leaves up to 2 ft. Long and 1 ft. Wide.

STEMS: Erect, branching, spiny leaf wings extend down onto stem, covered with dense fine hairs.

FLOWER: Solitary, terminal, 1 to 2 inches in diamter, violet to reddish colored. Bracts spine tipped.

ROOTS: Large fleshy taproot.

SEEDS: Deep brown to black, distinctly wrinkled, 3/16" long.

OTHER: Reproduce by seed only. Dense strands may be impenetrable to livestock.

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SCOTCH THISTLE (Onopordum acanthium L.) GROWTH HABIT: Biennial, sometimes annual, erect, up to 8 ft. Tall. Rosette formed first year, flowering stem elongates second year. LEAVES: Large, coarsely lobed, hairy on both sides, velvety gray appearance. Margins lined with sharp conspicuous spines, Basal leaves up to 2 ft. Long and 1 ft. Wide. STEMS: Erect, branching, spiny leaf wings extend down onto stem, covered with dense fine hairs. FLOWER: Solitary, terminal, 1 to 2 inches in diamter, violet to reddish colored. Bracts spine tipped. ROOTS: Large fleshy taproot. SEEDS: Deep brown to black, distinctly wrinkled, 3/16" long. OTHER: Reproduce by seed only. Dense strands may be impenetrable to livestock.