Weed
nodding beggartick, nodding bur-marigold
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.
Conical
Black with white ribs
Smooth between barbed ribs
Barbed awnsAwn:
A narrow, bristle-like organ, as on the glumes or lemmas of grasses (Poaceae).
are a continuation of barbed ribs.
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. have four longitudinal ribs.
Not listed
Not included
Asteraceae
Bidens cernua L.
Bidens cernua L. var. cernua
Bidens cernua L. var. dentata (Nutt.) B. Boivin
Bidens cernua L. var. elliptica Wiegand
Bidens cernua L. var. integra Wiegand
Bidens cernua L. var. minima (Huds.) Pursh
Bidens cernua L. var. oligodonta Fernald & H. St. John
Bidens cernua L. var. radiata DC.
Bidens glaucescens Greene
