Go to Midwest Weeds and Wildflowers Home Page

Waterhemp (Tall or Common)

Amaranthus tuberculatus (Moq.) Sauer

(includes plants once classified as Amaranthus rudis J.D. Sauer)

Amaranthaceae (Pigweed Family)

▲ seedlings

▲ ▼ young plants

▲ ▼ young plants

▲ ▼ young, mature plants

▲ ▼ young, mature plants

▲ ▼ young, mature plants

▲ ▼ young, mature plants

▲ ▼ young, mature plants

▲ ▼ plants showing different stem colors possible, from green to red

▲ ▼ mature plants, showing elongated inflorescences

▲ ▼ mature plants, showing elongated inflorescences

▲ ▼ mature plants, showing elongated inflorescences

▲ ▼ mature plants, showing elongated inflorescences

▲ ▼ mature plants, showing elongated inflorescences

▲ ▼ inflorescences

 

Amaranthus tuberculatus (Moq.) Sauer.; Common Waterhemp: (Bayer Code:  AMATU; US Code AMTU)

·         Warm-season, aggressive annual weeds, with upright, pyramidal to slender growth habit

·         Terminal inflorescences very long—often several feet tall

·         Has both male and female plants & inflorescences

      o   Female plant inflorescences appear more “sparse” than male inflorescences

·         Common in cultivated fields—often most common of  pigweeds—and in disturbed soils, roadsides, wetland and non-crop areas

·         Prefers more moist soil, but can be found in any soil type

·         Tall waterhemp (Amaranthus tuberculata) and common waterhemp (Amaranthus rudis) were considered as two separate species based on  minor seed characteristics differences, but now are considered all one species

·         Can readily hybridize with other pigweeds, resulting in weeds with varying pigweed/amaranth/waterhemp characteristics

·         Similar to palmer amaranth in long inflorescences, but waterhemp has narrow, lanceolate leaves, compared to diamond-shaped leaves of palmer amaranth

·         Can develop colonies of herbicide-resistant plants fairly easily where repeated use of one or similar herbicides is practiced—one of the new "superweeds"

 

Go to Midwest Weeds and Wildflowers Home Page

Updated 15 January 2019