Joshua Tree National Park, located in southeastern California, was designated a U.S. National
in 1994 by Congress. It had previously been a U.S. National Monument
since 1936. It is named for the Joshua tree forests native to the park. It covers a
land area of 790,636 acres (1,235.37 sq mi) - an area slightly larger than the state
of Rhode Island. A large part of the park, some 429,690 acres, is a designated wilderness
area. Straddling the San Bernardino County/Riverside County border, the park includes
parts of two deserts, each an ecosystem whose characteristics are determined primarily
by elevation: the higher Mojave Desert and lower Colorado Desert. The Little San Bernardino
Mountains run through the southwest edge of the park.
The higher and slightly cooler Mojave Desert is the special habitat of the Joshua tree for which the park is named. It occurs in patterns from dense forests to distantly spaced specimens. In addition to Joshua tree forests, the western part of the park includes some of the most interesting geologic displays found in California's deserts. The dominant geologic features of this landscape are hills of bare rock, usually broken up into loose boulders. These hills are popular amongst rock climbing and scrambling enthusiasts. The flatland between these hills is sparsely forested with Joshua trees. Together with the boulder piles and Skull Rock, the trees make the landscape out of this world.
Joshua trees dominate the open spaces of the park, but in among the rock outcroppings are piñon pine, California juniper, desert scrub oak, Tucker's oak, and Muller's oak. These communities are under some stress, however. The climate was wetter until the 1930s. The same hot and dry conditions that provoked the Dust Bowl affected the local climate. These cycles were nothing new, but the original vegetation did not prosper when wetter cycles returned, however. The difference may have been human development.
Cattle grazing took out some of the natural cover and made it less resistant to the changes. But the bigger problem seems to be invasive species, such as cheatgrass. These things deliver a double punch. During wetter periods, they fill in below and among the pines and oak. In drier times, they die back, but do not quickly decompose. This makes wildfires hotter and more destructive, which kills some of the trees that would have otherwise survived. When the area regenerates, these non-native grasses form a thick layer of turf that makes it harder for the pine and oak seedlings to get a roothold.
Below 3,000 feet, the Colorado Desert encompasses the eastern part of the park and features habitats of Creosote bush scrub Ocotillo, desert Saltbush and mixed scrub including Yucca and Cholla cactus. There are areas of such cactus density they appear as natural gardens. The lower Coachella Valley is on the southeastern side of the Park with sandy soil grasslands and desert dunes.
The only palm native to California, the California Fan Palm, occurs naturally in five oases in the park, rare areas where water occurs naturally year round and all forms of wildlife abound.
The rock formations of Joshua Tree National Park were formed 100 million years ago from the cooling of magma beneath the surface. Groundwater is responsible for the erosion that created the spheres from rectangular blocks. These prominent outcrops are known as inselbergs or a monadnock.
Nine established campgrounds exist in the park, three of which (Black Rock Campground, Indian Cove Campground, and Cottonwood Campground) provide water and flush toilets.
There are several hiking trails within the park, many of which can be accessed from a campground. Shorter trails, such as the one mile hike through Hidden Valley, offer a chance to view the beauty of the park without straying too far into the desert. A section of the California Riding and Hiking Trail meanders for 35 miles through the western side of the park. The lookout point at Keys View, towards the south of the park, offers views of the Coachella Valley and Salton Sea.
The park is popular with rock climbers and was originally a winter practice area while Yosemite Valley and other parts of the Sierra Nevada were snowbound, but later became an area of interest in its own right. There are thousands of named climbing routes, at all levels of difficulty. The routes are typically short, the rocks being rarely more than 230 ft in height, but access is usually a short, easy walk through the desert, and it is possible to do a number of interesting climbs in a single day.
Most of the park's roads are unpaved and require a vehicle with high ground clearance, and preferably one with four-wheel drive. The Geology Tour Road is another unpaved road located in the center of the park. Visitors with a four-wheel drive vehicle can use this road to take a self-guided tour. There are sixteen stops on the tour showcasing the region's geology. Of course the road we took from Twentynine Palms to Interstate 10 is paved-some things you just got to enjoy.
Unfortunately, we did not get to spend as much time exploring the park as we would have liked. Next trip we will take some of the back roads and maybe do a little camping.