Alias: Cotton thistle
- Stems: Broad spiny wings. Grows up to 8 feet tall.
- Leaves: Alternate, irregularly lobed and toothed, the
margins bearing sharp yellow spines. Occasionally 2 feet long,
but usually smaller.
- Flowers: Globeshaped, upright, spiny, 2 inches across
and purple. Flowering heads are numerous, 1 to 2 inches in diameter,
bracts all spine tipped.
- Seeds: Smooth and slender, and tipped by a cluster of
slender bristles; contained in 3/16-inch long, wrinkled fruit.
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
Control: Call your local weed board, agriculture extension
office, or other land management agency for information on current
Report all sightings to your local