Jawbone Canyon - Cross Mountain Area

Included in this area are the upper reaches of Jawbone Canyon and Water Canyons, Cross Mountain and Cottonwood Creek.

Several plant communities are present in this area, which borders the Mojave Desert. The dominant is the creosote bush scrub with Larrea tridentata, Yucca sp., rabbit brush, Chrysothamnus nauseosus, and some California juniper, Juniperus californica. Joshua trees, Yucca brevifolia, are present.

There is a scattering of oak woodland, with blue oak, Quercus douglasii, and gray pine, Pinus sabiniana. A small amount of grassland with fiddleneck, Amsinckia douglasiana, rice grass, Oryzopsis hymenoides, non-native red brome, Bromus madritensis ssp. rubens, and other species, may occur interspersed in the oak woodland or by itself.

Along the intermittent creeks there is a riparian community with willow, Salix sp., and cottonwood, Populus fremontii.

The area was well known for its wildflower displays which included five species of Oenothera and four Gilia spp., among others. At least two rare plants, Phacelia nashiana, and Eriogonum kennedyi var. austromontanum, occur in the vicinity.

Zoologically, the region is of interest, as there is a mix of Sierran and Mojave fauna with some elements of the coastal region. Thus, the coast horned lizard, Phrynosoma coronatum, is found here. A population of the Walker Pass pocket mouse, Perognathus xanthonotus, previously known only from the Walker Pass area, has been discovered here. The three quails found in California, the California, Gambel's and mountain, Lophortyx californica, Lophortyx gambeli, and Oreortyx picta, have been recorded in the area. The rare Mojave ground squirrel, Citellus mohavensis, occurs here.

Much of the area is underlain by Mesozoic granitic rocks; however, the Cross Mountain region is composed of Miocene and other Tertiary volcanics. The Jawbone fault traverses the area.

There are archaeological sites in this region.

Integrity: Portions of Jawbone Canyon have been very severely impacted by off-road vehicles and much of the area has been subjected to grazing. However, in the higher elevations and more rugged terrain the impact has been relatively minor.

Use: Research, educational, observational. Some private.

May 1977