Scientific NameAmbrosia bidentata
Other Common Names:
Leaves are opposite below and alternate above; have a lanceolate shape with no lobes and no leaf stalk. Often, the leaves will have one pair of large teeth on the lower half of the leaf. Leaves are densely hairy mostly on the underside. The upper side of the leaf may be hairless.
This is an annual weed that is highly branching and can grow up to 3 ft tall. Both the stem and leaves are densely covered in long, straight (not woolly) hairs. Often, the leaves will have one pair of large teeth on the half of the leaf nearest to the stem; otherwise, the leaves may be finely toothed or may not have any teeth at all.
Flower Seed Head
Flowers are non-showy. The inflorescence is a tall, ascending spike.
Hairy bur. Fruit has several short stiff spines and is beaked at one end.
Commonly found in prairies and waste areas
upright and nonwoody
Thorns or Spines
Approximate Flower Diameter
Dominant Flower Color
Stem Cross Section
round or oval