Flower
common tansy, tansy, golden-buttons, hierba lombriguera, garden tansy
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.
Obovate
Light brown
GranularGranular:
Resembling or consisting of small grains or particles.
and sharp longitudinal corners
Base and apexApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar.
are truncated. Some pappusPappus:
Modified calyx in Asteraceae, composed of hairs, bristles, awns, or scales. The pappus-like structure attached to milkweed seeds is termed a coma. 
remains; flat sides.
Sharp longitudinal ridges with flat interspaces make the 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. appear four- to six-sided in cross section. ApicalApical:
The distal end of the fruit or seed away from the point of attachment or attachment scar. collar is evident on most 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..
State Noxious Weed: Montana, Wyoming
Not included
Asteraceae
Tanacetum vulgare L.
Chrysanthemum vulgare (L.) Bernh.
Tanacetum boreale Fisch. ex DC.
Tanacetum vulgare L. var. crispum DC.
