burrnut, Tribulus cistoides

Burrnut is also called puncture-vine, for good reason. The spiked fruit earn the generic name from medieval weapons of war. Those were four-spiked iron pieces laid down to cripple enemy troops and animals. The fruit of Tribulus has been known to puncture tires. But the almost one-inch flowers are very attractive on vines that trail along the ground. This shot was taken at a gas station, but modern tires are pretty tough. It has been planted to restore ground cover in disturbed areas. A tropical native, with us now in FL, GA, HI, LA, and TX. Monroe Co FL, 1/26/13.