BACKGROUND: Scotch thistle is native to Europe and eastern Asia. It grows well in waste areas, pastures, range land, and along canal and stream banks.
Other common names: Cotton thistle
DESCRIPTION: This biennial plant commonly grows three to eight feet tall, but it may grow as high as 12 feet. Rosettes may be four feet wide. Large spiny leaves up to two feet long and one foot wide are covered with dense hair, giving a grayish blue-green coloration. The flowers are violet to reddish with spine tipped bracts, blooming in mid summer.
CONTROL: Biocontrol research is currently being conducted. Herbicides can offer good to excellent control when applied between rosette and pre-bud stages. Contact your local state or county weed specialist for specific updated information.
Photos and text taken from Noxious Weed Field Guide for Utah
