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Scotch Thistle

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Scotch Thistle
Onopordum acanthium
 
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.
Adult

This biennial plant commonly grows three to eight feet tall, but it may grow as high as 12 feet.
Flower

The flowers are violet to reddish with spine tipped bracts, blooming in mid summer.
Weed 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.
Winged stems

Stems are heavily ridged and very spiny.
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