Scientific Name: Amaranthus hybridus

Common Name: smooth pigweed

Other Common Names: smooth amaranth, red amaranth, slim amaranth

Synonyms: Amaranthus chlorostachys, Amaranthus incurvatus, Amaranthus patulus

Habit: This erect summer annual flowers from June through October.

Leaves: The alternate leaves are oval to egg shaped. The leaves are green on the upper surface and light green to magenta on the lower surface. The stems are densely hairy with short hairs.

Identifying Characteristics: This plant can be distinguished from other pigweeds by it's smaller, less bristly, limp flower spikes.

Flower Seed Head: The small greenish flowers occur in terminal spikes. The male and female flowers occur in different places, the males on the terminal spikes, and the females in smaller spikes of flowers at the leaf axils.

Seed Fruit: The glossy black seeds each form inside a 2 mm long utricle that splits open at maturity.

Where Found: This plant can be found in pastures, along roadsides, and other disturbed soils.

  • Life cycle: summer annual

  • Milky sap: Not Present

  • Plant type: Herb

  • Thorns: Not Present

  • Plant family: Amaranthaceae

  • Leaf arrangement: alternate

  • Leaf shape: oval; round

  • Leaf margin: entire; wavy

  • Stem hairs: has hairs

  • Flower color: purple; green

  • Growth habit: upright and nonwoody

  • Stem: round or oval

  • Leaf structure: simple

  • Leaf hairs: has hairs

  • Root structure: taproot

  • Leaf stalk: shorter than leaf