Caltrop Family (zygophyllaceae)
California fagonbush (Fagonia laevis) -- in March -- Organ Pipe Cactus National Monument, AZ red & pink
Texas lignum-vitae (Guaiacum angustifolium) -- in April -- Big Bend National Park, Texas blue & purple
hairy caltrop (Kallstroemia hirsutissima) -- in September -- Villanueva State Park, NM yellow & orange
creosote bush (Larrea tridentata) -- in January -- Joshua Tree National Park, CA yellow & orange
creosotebush (Larrea tridentata) -- in April -- River Road East, Big Bend National Park, Texas yellow & orange
creosote bush (Larrea tridentata) -- in March -- Tonto National Forest, AZ
puncture vine (Tribulus terrestris) -- in August -- High Plains Environmental Center, Loveland, CO yellow & orange
puncture vine (Tribulus terrestris) -- in August -- North Shields Ponds, Fort Collins Natural Area, CO