While tumbleweeds may be no more than a prop in your favourite Western, they are the primary antagonist in the story of one of the fastest plant invasions in the history of the United States.

Though the plant itself is dead, the tumbleweed stage is how it spreads its seeds for the next generation. Each plant carries ...

Tumbleweed is one of the most iconic symbols of the old American West, made famous in hundreds of movies. But this invasive plant did not actually reach US shores until the latter part of the 19th ...