Mountains near San Carlos, with Brittlebush (Encelia farinosa), Creosote Bush (Larrea tridentata), and Organ Pipe Cactus (Stenocereus thurberi).

Geologists' descriptions include "tertiary rhyolite flows, volcanic rock, lahar deposits, granite and rhyolite outcroppings................."

 

Washingtonian palms cling improbably to the upper slopes in narrow, steep ravines.

 

Coastal northern Sonora, Mexico.

Done