Why tumbleweeds may be more science fiction than Old West
Salsola plants form tangled balls of dead foliage to spread their seeds

When mature and dry, Salsola plants separate from their roots and roll around to spread their seeds, forming tumbleweeds.
Jon Sullivan/Flickr (CC BY-NC 2.0)
This article is only available to Science News subscribers.
Subscribers, enter your e-mail address to access our archives.
