Broad spiny wings. Grows up to 8 feet tall. Alternate, irregularly lobed and toothed, the margins bearing sharp yellow spines. Occasionally 2 feet long, but usually smaller. Flowering heads are numerous, 1-2 inches in diameter, bracts all spine tipped.
Scotch thistle is a spiny biennial.
The whole plant appears hairy or woolly. It usually occurs along roadsides, in waste areas, and on rangelands along stream courses, lower slopes, and bottomland where moisture occurs. It often forms dense stands impenetrable to livestock. Call your local weed board, agriculture extension office, or other land management agency for information on current control methods.