Spanish soldiers, who frequently conducted sweeps of the Los Angeles Basin abducting children to San Gabriel Mission and raping women, destroyed the village prior to 1785 as part of a raid.

This tectonic pressure created deeply fractured and fissured sheets of rock that began to shift direction about 25 million years ago.

These geologic conditions restrain water absorption towards the rockier higher elevations, which allow runoff to hydrate the base, creating a more habitable (friendly) environment for plants.

Because of the transverse (east-west) orientation of the range, this effect is pronounced on the north slope due to the lower rates of evaporation caused by sunlight directed from the south.

The dominant plant community is coastal sage scrub, known for its high adaptations for long dry summers and is drought deciduous.

Mammals in the San Jose Hills include bobcats, coyotes, gray fox, skunks, opossums, squirrels, and other rodents.

Two parks with significant natural areas are located in the eastern portion of the San Jose Hills; Ganesha Park include four picnic pavilions, a community center, amphitheater style band Shell, Olympic size swimming pool with slide, basketball courts, two lighted tennis courts, wildlife and hiking areas, and restroom facilities.

Bonelli Park facilities include boat launch ramps, vehicle camp sites, trails for hiking, biking and horseback riding, play equipment, gazebos, and group rental picnic areas.

The Voorhis Ecological Reserve in the northwest part of the Cal Poly Pomona campus contains 31 ha of coastal sage scrub and oak woodland.

Near the Grand Avenue corridor, Heritage Gardens Historical Park, located on the north slope, was recently redeveloped to include new hiking trails.