Centaurea nigra. N.O. Compositae.
Synonym ► Hard-head, Hard-hack, Ironweed (these due to its resistance to the mower’s scythe), Black Ray Thistle, Star Thistle.
Habitat ► Pastures and meadows.
Features ► Stem grows from one to two feet, angular, tough, very much branched on alternate sides. Leaves dull green, hard appearance, downy underneath, irregularly notched edges, upper sessile, lower stalked. Flowers thistle-shaped ; reddish-purple, hair-like petals grow from nearly black, scaly knob. Fruit without pappus, surrounded by bristles. Taste, slightly salty.
Part used ► Herb.
Action ► Tonic, diaphoretic, diuretic.
As a general tonic for most of the purposes for which Gentian is used. Knapweed is held in some quarters to equal Gentian in all-round efficacy, but the latter is much more frequently prescribed. The ounce to pint infusion is taken in wineglass doses.