Russian Thistle
Tumbleweed
Salsola tragus
Photographed in Phoenix, Maricopa Co., Arizona. May 2, 2004
Photographed along the Gila River near Goodyear, Maricopa Co., Arizona. December 2006.
ANNUAL : Robust weed of disturbed ground. Plants may grow to
several meters in diameter and take a nearly spherical shape.
Eventually the dried plant breaks loose from its root system to be tumbled
along by the wind - dispersing its seeds along the way.
ARMED. Many of the leaves are stiff and sharply spine-tipped. Lower,
dead leaves remain firmly attached and sharpened deterring bare-handed weed
pullers and herbivores alike.
LEAVES: Leaves are narrow and somewhat thickened/fleshy. Tips are
spinescent.
RANGE: Introduced. Frequent throughout the Sonoran Desert in Arizona and Mexico at
roadsides, near agriculture and river flood plains and in major washes. Several
closely related, similar species have been delineated by botanists.
FRUIT: Dry single-seeded capsule encircled by winged bracts.
FLOWERS: Green with papery bracts and mostly inconspicuous. Pollen is
dispersed by wind and is allergenic for many people.