(Centaurea solstitialis L.)
GROWTH HABIT: Annual, erect, rigid branching stems.
LEAVES: Basal leaves deeply lobed, upper leaves not lobed, small, sharply pointed.
STEMS: Rigid, covered with a cottony fiber, to 30 inches tall, winged structures.
FLOWER: Yellow, terminal, flower bracts are tipped with straw-colored, ¾ inch thorn.
SEEDS: Smooth, light-colored, often darker mottled, 1/8 inch long, notched just above the base.
OTHER: Causes "chewing disease" in horses.