Zygophyllaceae

Tribulus terrestris

Puncture Vine

Mat prostrate to 6 ft. across. Leaves divided, leaflets oval, opposite, 6–12. Flowers small, yellow. Fruit splits into 5 nutlets, each nutlet with 2–4 hard sharp spines. Grows in dry disturbed soils. Mediterranean. This pernicious weed causes flat tires and injured feet, and is named caltrop after a 4-spiked weapon used on the ground to obstruct moving armies.

• Rarity: Common
• Flowering Time: All Summer
• Life Cycle: Annual
• Height: mat
• Habitat: Disturbed, Shrub-Steppe
• Found In:
• Native: No