Prostrate Pigweed
Tumble Pigweed
Amaranthus albus
Photographed in eastern Maricopa Co., Arizona. May 10, 2008. A high resolution image has been added to the Wikimedia Project.
An etching by Hippolyte Coste (1858-1924), Flore descriptive et illustrée de la France, de la Corse et des contrées limitrophes, published from 1900 to 1906 by Paul Klincksieck. The image is also part of the Wikimedia Project.
ANNUAL : Robust weed of disturbed ground evident from mid spring though autumn. Often growing prostrate on the
ground but may begin growing upright and later forming a tumbleweed when
mature. Plants may grow to over a meter in
diameter. Eventually the dried plant may break loose from its root system to be
tumbled along by the wind - dispersing its seeds along the way.
FLOWERS: Separate male and female flowers on same plant. Small and green
arranged in small clusters at leaf axils. Three stamens in males and usu. three
style branches in female.
RANGE: Common in the Sonoran Desert in Arizona and Mexico especially
where human disturbance is frequent. Agricultural fields, roadsides and washes
- especially those used by off road vehicles. An introduced weed from Eurasia
that has spread across much of North America.
LEAVES: Leaves are elyptic and in desert areas mostly less than
5 cm long.
FRUIT: Dry, single-seeded, circumscissile capsule closely subtended by greenish bracts.
UNARMED. However, the bracts around the flowers when dry can be a bit
prickly.