Canada thistle

(redirected from Canada thistles)
Also found in: Dictionary, Medical, Encyclopedia.
  • noun

Synonyms for Canada thistle

European thistle naturalized in United States and Canada where it is a pernicious weed

References in periodicals archive ?
Quackgrass is more persistent and more difficult to eradicate than the Canada thistle, hence any method which will eradicate quackgrass will surely destroy Canada thistles or any other perennial weed.
This means almost sure death to Canada thistles, but often fails with quackgrass and must be adopted advisedly.
Covering with paper: Quackgrass and Canada thistles in patches not over two rods square can sometimes be economically killed by cutting the weeds close to the ground just when in bloom and covering with tar or some other heavy building paper.
Growing alfalfa: Canada thistles have been completely eradicated where good stands of alfalfa were secured and maintained for three years or more.
Canada thistles in many cases spread only by the roots and bear no seeds, while in other instances, where the conditions are favorable, a large amount of seed is produced.
Full browser ?