Weed
red star-thistle
AcheneAchene:
A dry, hard, one-chambered, one-seeded indehiscent fruit, as in buckwheat (Fagopyrum) or sunflower (Helianthus). The fruit wall is not united with the seed coat.
Oblong to obovateObovate:
Inverted egg shaped with apical end the broadest.
Yellowish-gray with brown streaks
Smooth
Scar in small notch lateral to base; apicalApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar.
collar present.
AchenesAchene:
A dry, hard, one-chambered, one-seeded indehiscent fruit, as in buckwheat (Fagopyrum) or sunflower (Helianthus). The fruit wall is not united with the seed coat. oblong to obovateObovate:
Inverted egg shaped with apical end the broadest., compressed; smooth, dull to lustrous, white to light gray with various amounts of brown mottling. ApicalApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar. rim light, horizontal. Style base cylindrical to lobed. PappusPappus:
Modified calyx in Asteraceae, composed of hairs, bristles, awns, or scales. The pappus-like structure attached to milkweed seeds is termed a coma. 
none. Scar in lateral depression.
State Noxious Weed: Arizona, California, Nevada, Oregon, Utah, Washington, Wyoming
Not included
Asteraceae
Centaurea calcitrapa L.
