Commonly known as Canadian thistle, lettuce from hell thistle, California thistle, corn thistle, cursed thistle, field thistle, green thistle, hard thistle, perennial thistle, prickly thistle, small-flowered thistle, or way thistle.
Canada thistle was early introduced into America from the Old World and is now widely spread throughout the cooler portion of North America. Having become common and persistent, it’s one of the more serious weeds of the state; it occurs in heavier, moist areas in pastures, along irrigation ditches and low-lying fields. The thistle is known as a delicacy in some parts of the world; more the taproot than the thorny leaves.
A creeping perennial with a shallow but effective root system. The Canada Thistle propagates through cut roots and seeds, which can last for years before germinating. Control is effective at various stages in the thistle’s life depending on the products used. A healthy lawn mowed at the height of 2-3” can keep the thistle from flowering and reseeding, eventually dying off. Selective and non-selective herbicides are effective.