Tribulus terrestris
Common names: PUNCTUREVINE, BURNUT, BULLHEAD, (TORRITO) Arizona, California, and Texas deserts: (Tribulus terrestris). Pale yellow. Summer. Caltrop family. Size: Prostrate, stems 2 to 6 feet long.
A troublesome annual vine-like weed naturalized from southern Europe, the Puncturevine has established itself throughout the Southwest below 7,000 feet. Although fairly readily controlled by cultivation, the plant spreads rapidly in sandy, dry wastelands, often taking over vacant lots in towns, and areas in the desert where it finds sufficient moisture.
The fruits, which are produced in quantities, are armed with strong spurs which become embedded in the feet and fur of animals and in automobile tires. Fruits are also carried by irrigation or flood waters. Although the spurs are too short to puncture automobile tires, they make bicycles almost useless in some localities, and are an aggravation to children who go barefoot—and to dogs.
Flowers and fruits in various stages of maturity may be found on this fast-growing plant at almost any time during the summer months. Botanically, Puncturevine is closely related to the Creosotebush and also to the Arizona-poppy.
YELLOW