Bull Thistle

Bull Thistle
Bull Thistle. Cirsium vulgare.
Asteraceae, the daisy, sunflower or composite family.

Plant: Robust, branching, very spiny plants, 2'-6', with large, terminal, pink-purple flower heads.
Flowers: Bright pink to purple heads, 1.5"-2", composed entirely of disk flowers arising from a large swollen base covered by very spiny bracts.
Leaves: Alternate, basal in first year, pinnately lobed and toothed, and spiny. The stem, in contrast to canada thistle, is spiny.
Fruit: Dry seeds attached to silky hairs (thistledown) released from the heads when they open at maturity.
Blooming: Mainly July-August.
Habitat: Fields, waste areas, roadsides.

Comments: This is a very spiny plant, often a weed, introduced from Europe. It is a biennial, forming a rosette of basal leaves the first year, and growing up and flowering the second. Plants thus have a solitary nature as opposed to the dense stands typical of canada thistle (which also is generally more delicate and less spiny). Like other thistles (e.g. the artichoke), tender parts are edible. Young stems sometimes contain soft pith (older ones become hollow). The flowers can supposedly be used to curdle milk as a substitute for rennet.

Where to find it: In various locations in open areas around the pond.