The Tumbleweed

What could be a more iconic symbol of the American West than the tumbleweed? From an early age we are indoctrinated with rustic images of tumbleweeds blowing across the high desert. But, did you know that there is very little about this iconic plant that could be considered American? That's right, our most common species of tumbleweed, Salsola tragus, is actually from Russia.

Salsola tragus, also known as Russian thistle, was accidentally introduced to South Dakota in the 1800's in a shipment of flaxseed. It is not actually a thistle at all but rather a member of the family Chenopodiaceae. Since then it has managed to spread throughout most of North America. In arid regions it has become quite a pest.

The tumbling aspect of its ecology has to do with seed dispersal. When the seeds mature, the plant dries up and breaks at the base. As the wind proceeds to blow the tumbleweed around it sprays seeds in every direction. Thanks to this novel method of seed dispersal it is easy to see how this plant is so common as to literally become synonymous with the American West. 

Photo Credit: VancityAllie

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