![Shana Welles found this tumbleweed in Riverside and put in the bed of her pickup truck. Credit: UC Riverside](http://swtreesandturf.com/wp-content/uploads/2016/06/tumbleweed0516-150x150.jpg)
By Sean Nealon Two invasive species of tumbleweed have hybridized to create a new species of tumbleweed that University of California, Riverside researchers found has dramatically expanded its geographic range in California in just a decade. The UC Riverside researchers…