Occupying the park’s southern and eastern regions, the Colorado Desert is a western extension of the larger Sonoran Desert. This arid landscape is defined by its distinctive plant life, including the tall, spindly ocotillo and the notorious “jumping” cholla cactus, whose barbed joints readily attach to passersby. Despite its harsh conditions, this desert teems with life adapted to the intense heat and minimal rainfall.

To the north, the Mojave Desert extends into the park, bringing with it the emblematic Joshua tree (Yucca brevifolia), for which the park is named. These otherworldly, twisted plants dominate much of the western half of the park, thriving in the slightly cooler, higher-elevation environment. This section is also home to unique wildlife, rugged rock formations, and sweeping desert vistas.

Above 4,000 feet (1,219 meters) in the Little San Bernardino Mountains, a third ecosystem emerges. Here, cooler temperatures and increased moisture support a woodland community of pinyon pines and California junipers. This area provides essential habitat for wildlife seeking refuge from the more extreme desert zones.