Bull Thistle (Cirsium vulgare)

Bull Thistle (Cirsium vulgare).
The Bull Thistle (Cirsium vulgare), introduced from Europe and Asia, is a tall plant with exceptional fortification. Unlike other thistle, the Bull Thistle is covered from top to bottom with defensively sharp spines. Most other thistles only have spines on their leaves. The Bull Thistle starts it's first year as a rosette, while it establishes a deep tap root to supply nutrients and stabilize it in the second year, when it can grow to five or six feet tall. It's in this second year that it flowers and produces the hundreds of air born seeds to start the cycle all over. The seeds are carried on silky parachutes if not eaten first by the American Goldfinch and other birds. The goldfinches will gather in groups, if the thistle are abundant, and sit on the flower heads plucking the parachutes out and shaping off the seeds. They also use the thistle down for lining in their nests as do other small birds and rodents.
While the Bull Thistle is a noxious weed, it is easily controlled by cutting or digging. It is, however, a delight to let some grow in a place where you can watch the Goldfinches (wild Canary's) work them. Picking out seed after seed and letting the parachutes blow in the breezes. For all their spiny defenses these small birds seem impervious to them, or they just ignore them.