Puncture Vine
Tribulus terrestris
Caltrop family (Zygophyllaceae)
This bane of the bicycles existence and pain of the dog's paws should be banned by federal proclamation. Imported from Europe at least a century ago, it has now spread through the U.S. along roads, bike paths, and railroads. It is successful under hot and dry conditions and can out-compete other plants in such areas. A typical Puncturevine plant will produce 200 to 5,000 seeds during one growing season. The plant was described and named by Linnaeus in 1753 from plants collected in Europe.

©2004 Anthony Valois and the National Park Service