Tumbleweeds Tumbleweed is a botanical success story in barren habitats throughout much of the world, including Eurasia, Australia, and North America. According to some accounts, despite its abundance in some areas of the world, tumbleweed is apparently extinct in its original native habitat in Russia. "Tumbleweed," "Russian thistle" and "wind witch" are common names for this symbol of the American west. Virtually everyone recognizes mature the Russian thistle, which looks like the skeleton of a normal shrub. Plants may be as small as a soccer ball or as large as a Volkswagen beetle. Most people, however, would fail to recognize the seedling and juvenile plant’s bright green, succulent, grass-like shoots, which are usually red or purple striped. Inconspicuous green flowers grow at axils (where leaf branches off of stem) of the upper leaves, each one accompanied by a pair of spiny bracts. Mice, bighorn sheep and pronghorn eat the tender shoots.
As it rolls down a desert road, a Russian thistle plants do what they do best, disperse seeds, which typically number 250,000 per plant. Seeds are unusual in that they lack any protective coat or stored food reserves. Instead, each seed is a coiled, embryonic plant wrapped in a thin membrane. To survive winter without a warm coat, the plant does not germinate until warm weather arrives.
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