As a group of plants, thistles are well known for their spiny leaves and large pinkish purple flower heads. Most species are biennials, producing only a basal rosette of leaves in their first year. The characteristic flowering stalks are not produced until the plant’s second year. Bull thistle (Cirsium vulgare), although native to much of Europe, has naturalized across much of North America.  It is a large thistle generally found in fields and waste places. It can grow 3 to 5 feet tall, and has long spine-tipped “wings” along the length of its stem. The numerous spiny, divided, alternate leaves, are pale and somewhat wooly on the underside. 

The large flower heads make field thistles attractive to a number of pollinators, from butterflies and bees to hummingbirds. It serves as a host plant for the painted lady butterfly. Bumblebees, like the one pictured above, make use of the blossoms to gather pollen. The flowers typically bloom in late summer or early fall, before producing seeds with long downy plumes that aid wind dispersal. These seeds are attractive to seed eating birds, such as the American goldfinch.