Common Waterhemp

Amaranthus tuberculatus

Alternate names
Tall Waterhemp, Waterhemp

Weed Description
An erect summer annual measuring 3 meters tall, commonly found through central and eastern United States. Common waterhemp is primarly found in cultivated fields, stream banks, and waste sites.

Seedlings
Seedling leaves are oar shaped, first true leaves appear lance-shaped and have a minute notch at the tip of the leaf.

Leaves
Leaves are without hairs are oval to lanceolate in shape and have a waxy appearance. Common waterhemp leaves are alternate and measure 1-15cm in length and 0.5-3.0cm in width.

Stems
Stems are brightly colored and range in color from murky red or pink to green. Stems are without hairs and appear glossy.

Flowers
Common waterhemp is dioecious having male and female parts on seperate plants. Flowers and bracts are green to reddish pink and have spikes that are densely packed.

Roots
Fibrous root system from a well developed tap root.

Seeds
Black to dark red in color and measure 0.8-1.0mm in diameter.

Identifying Characteristics
A long petiole, Waxy and hairless stems, and leaves are prime characteristics of common waterhemp. This summer annual produces a large seedhead and commonly reaches 6 feet in height. Seeds are difficult to see with the naked eye and measure 1mm in diameter.

Office of Programs

University of Missouri

Common Waterhemp

Amaranthus tuberculatus