Home Weed ID Publications Dictionary Links FAQs Login About us		Plant Description: Name: Canada thistle Scientific Name: Cirsium arvense Family: Compositae Type: Broadleaf Lifecycle: Perennial Habit: Canada Thistle produces flowers from about June until August. Generally new shoots began to form in January. The species spreads by creeping roots which in turn causes Canada thistle to often form dense patches. Leaves: Leaves are generally oblong with edges that are lobed and spiny. Leaves are dark green and smooth on top portion and light green and often hairy on the lower portion. Leaves are attached to stems by way of a clasping base. Leaf Arrangement: Alternate Characteristics: The plant reproduces by seeds and dense patches of shoots emerge from creeping roots. Flower Seed Head: Small lavender flower heads consist of as many as 100 lavender tubular flowers. Flower heads are flask-shaped, 1/4 to 3/4 inch wide. The flower heads are produced singly or in groups of 2 to 5 at the ends of stems and axillary branches. Seed Fruit: Mature seeds are brown, 3/16 inch long. A plume of tannish silky hairs is attached to one end. Where Found: The Canada thistle plant grows in cultivated fields, pastures, rangelands, roadsides, waste places, and other open areas. Control Options Related Plants Terms and Definitions Additional Images:
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