Scotch Thistle
Onopordum acanthium

Adult
Scotch Thistle adult
This biennial plant commonly grows three to eight feet tall, but it may grow as high as 12 feet.
Rosette
Scotch Thistle rosette
First year rosettes are 5 to 12 inches across. Second year 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.
Weed Infestation
Scotch Thistle infestation
Scotch thistle is native to Europe and eastern Asia. It grows well in waste areas, pastures, range land, and along canal and stream banks.
Flower
Scotch Thistle flower
The flowers are violet to reddish with spine tipped bracts, blooming in mid summer.
Winged stems
Scotch Thistle stem
Stems are heavily ridged and very spiny.
 
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