Milpitas Wash, Proposed Wilderness

Milpitas Wash; © John Dittli

Size: Approximately 17,050 acres

Management Agency: Bureau of Land Management, El Centro Field Office

Location: In Imperial County, west of Highway 78 between Palo Verde and Glamis.

Maps: BLM Desert Access Guide Trigo Mountains

Landscape and History

Milpitas Wash is near the southern end of the Mule Mountains and the Opal Hill Mine. The floodplain habitat is covered with braided and tumbled washes, scoured by centuries of natural forces at work. Visitors can see petrified palm roots that were once part of an ancient, lush landscape. Native Americans used the creosote bush as a sunscreen and potent antioxidant for the treatment of blood poisoning and hepatic diseases.

Wildlife and Plants

The Milpitas Wash region supports the largest Sonoran Desert woodland in the North America. Most of the trees are legumes: mesquites, acacias, palo verdes, and ironwoods; and there are also desert willows. The abundance of old‐growth trees, with most standing over 15 feet high, gives the area a lush character rarely found in the desert.

Among these aged trees, wildlife flourishes. The threatened Desert tortoise, mountain lions, long‐eared owl, leaf nose bat, merriam and desert kangaroo rats, long tail and little pocket mice, Bullockʹs and hooded orioles, towhees, white‐crowned sparrows, and Brewerʹs sparrows, warblers, black‐headed grosbeaks, diamondback rattler, and the endangered gila woodpecker all make their homes here.

Activity Highlight

Rock hounding. The Milpitas Wash Road passes by nearby Hauser Geode Beds, a popular winter haven for rock collecting. Fire agates and geodes are among the treasures often found.

For More Information

Monica Argandoña, Desert Program Director, California Wilderness Coalition
margandona@calwild.org | (951) 205 6004