Prior to mining operations commencing there, the mountains were heavily forested with large Rocky Mountain Douglas-fir (Pseudotsuga menziesii glauca) and other conifers, but these were all cut down for housing needs and to feed the ore smelting furnaces in Douglas, Arizona, approximately 20 miles due east.

Common wildlife species include desert mule deer (Odocoileus hemionus eremicus), Coues' White-tailed deer (O. virginianus couesi), Collared Peccary (Pecari tajacu) (locally known as javalinas), various types of rodents, lizards and a wide variety of birds.

The upper ridges of the mountains consist primarily of a very hard brecciate limestone, and it is very common to find fossils of clams and snails imbedded in them.

Over a billion tons of copper were extracted from the mine, along with significant quantities gold, silver and lead.

Under this part of the Mule Mountains are many mining tunnels dug in pursuit of the rich copper ore. Today, Bisbee (also known as the "mile-high city," at elevation 5,300 ft or 1,600 m) is largely a tourist town and retirement community along the slopes of Tombstone Canyon in the heart of the Mules.