Canada Thistle      Cirsium arvense (L.) Scop.
Photographs by Dr. Michael Pfeiffer
Sign Invasive. Noxious weed in many states.
Plants
click for a larger image
Plants and Roots
click for a larger image
Roots
click for a larger image
Plant
click for a larger image
Foliage
click for a larger image
Foliage and Flowers
click for a larger image
Flower and Foliage
click for a larger image
Flower
click for a larger image
Flower and Foliage
click for a larger image
Small Plant
click for a larger image
Seed
click for a larger image
Seed Head
click for a larger image
Breaking Dormancy
click for a larger image
Breaking Dormancy
click for a larger image
Breaking Dormancy
click for a larger image
Perennial