Shrubs, 0.5-3m tall, widely spaced, usually with bare ground between. Very similar in appearance to Mojave Creosote Bush Scrub (34100), but with greater species and life form diversity including several succulents. Growth occurs form winter to early spring (or rarely at other seasons) if rainfall is sufficient. Shrubs may be dormant for long periods. Many species of ephemeral herbs may flower in late February and March (earlier than in Mojave Creosote Bush Scrub (34100) if the winter rains are sufficient. This is the basic creosote shrub of the Colorado Desert.
SITE FACTORS:
Well-drained secondary soils of slopes, fans and valleys rather than upland sites with thin residual soils or sites with high soil salinity. Winter temperatures seldom below freezing.
DISTRIBUTION:
Colorado Desert Region from the Little San Bernardino Mountains, south and eastward into Baja California, southern Arizona and Sonora. The dominant plant community below 2,500 or 3,000 feet (760 or 910m). Intergrades broadly with Mojave Creosote Bush Scrub (34100) in southeastern San Bernardino County and eastern Riverside County.
UPDATE: 11/97
Source: Holland, 1986
Digital Text: NatureBase