Joshua Tree National Park

This article is about the national park. For other uses, see Joshua tree (disambiguation).

Joshua Tree National Park
IUCN Category II (National Park)
Location	Riverside and San Bernardino counties, California USA
Nearest city	Twentynine Palms, San Bernardino
Coordinates	33°47′18″N 115°53′54″W
Area	790,636 acres (1,235 sq mi; 319,959 ha)
Established	October 31, 1994 (1994-10-31)
Visitors	1,337,459 (in 2010)
Governing body	National Park Service

Joshua Tree National Park on a 2003 Landsat image

Joshua Tree National Park is located in southeastern California. Declared a U.S. National Park in 1994 when the U.S. Congress passed the California Desert Protection Act (Public Law 103-433), it had previously been a U.S. National Monument since 1936. It is named for the Joshua tree (Yucca brevifolia) forests native to the park. It covers a land area of 790,636 acres (319,959 ha) or 1,235 square miles – an area slightly larger than the state of Rhode Island. A large part of the park, some 429,690 acres (173,890 ha), 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.

Geography and botany

The park is named after the Joshua tree.

Mojave Desert

The higher and slightly cooler Mojave Desert is the special habitat of Yucca brevifolia, 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 otherworldly.

Joshua trees dominate the open spaces of the park, but in among the rock outcroppings are piñon pine, California juniper (Juniperus californica) and scrub 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.

Colorado Desert

Below 3,000 feet (910 m), 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 (Cylindropuntia bigelovii). 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 (Washingtonia filifera), occurs naturally in five oases in the park, rare areas where water occurs naturally year round and all forms of wildlife abound.

Geology

Giant Marbles

Climbing the Old Woman Rock

North Horror Rock at Hall of Horrors area at Sheep Pass

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 outcroppings are known as inselbergs or a monadnock.

Recreation

Camping

Nine established campgrounds exist in the park, three of which (Black Rock Campground, Indian Cove Campground, and Cottonwood Campground) provide water and flush toilets. A fee is charged per night for each camping spot. Reservations are accepted at Black Rock Campground, Indian Cove Campground, and Cottonwood Campground, while the six other campgrounds are first-come first-serve. Backcountry camping, for those who wish to backpack, is permitted with a few regulations.

Hiking

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.

Nature walks inside the park include:

• Hidden Valley
• Indian Cove
• Cholla Cactus Garden

Longer trails include:

• Boy Scout Hiking and Equestrian Trail
• Contact Mine
• Fortynine Palms Oasis
• Lost Horse Mine
• Lost Palms Oasis
• Ryan Mountain
• Warren Peak

Climbing

Climbers in Hidden Valley Campground in March 2008

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 (70 m) 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. The rocks are all composed of quartz monzonite, a very rough type of granite made even more so as there is no snow or ice to polish it as in places like Yosemite.

Driving

Most of the park's roads are unpaved and require a vehicle with high ground clearance, and preferably one with four-wheel drive. In August 2011, the director of Dutch club 013 and his girlfriend died of heat stroke in a remote part of Joshua Tree National Park, allegedly searching for a Joshua tree that had been featured in the album artwork of The Joshua Tree, a studio album released in 1987 by the Irish rock band U2. Their vehicle, a Dodge Charger rental car with rear-wheel drive and low ground clearance, was found stuck on Black Eagle Mine Road, an unpaved road in a remote part of the park. In reality, the site of that specific tree, which fell down in 2000, is located near Darwin, California, more than 300 miles driving distance from Black Eagle Mine Road.

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.

Birding

There are over 250 species of bird in the park including resident desert birds such as the Greater Roadrunner and Cactus Wren as well as Mockingbirds, Le Conte's Thrasher, Verdin and Gambel's Quail. There are also many transient species that may spend only one or two seasons in the park. Noted birding spots in the park include: fan palm oases, Barker Dam and Smith Water Canyon. Queen Valley and Lost Horse Valley also provide good birding but with a different range of species because of the lack of water. These are often good places to see Ladder-backed Woodpecker and Oak Titmouse. A USGS Bird Checklist of "what, when, and status" has 239 species listed for the park.

Astronomy

Joshua Tree is a popular southern California location for amateur astronomy and stargazing, along with nearby Anza-Borrego Desert State Park. Joshua Tree is well known for its dark skies, which are largely free from southern California's extreme light pollution. The park's elevation and dry desert air, along with the relatively stable atmosphere in southern California, often make for excellent astronomical observing conditions. Joshua Tree's sky darkness ranges from a green to a blue rating on the Bortle Dark-Sky Scale.

Wildlife

Many animals make their homes in Joshua Tree. Birds, lizards, and ground squirrels are most likely to be seen because they are largely active during the day. However, it is at night that desert animals come out to roam. Mostly nocturnal animals include: snakes, bighorn sheep, kangaroo rats, coyotes, and black-tailed jackrabbits.

Animals that thrive in Joshua Tree often have special adaptations for dealing with limited water and high summer temperatures. The smaller mammals and all reptiles take refuge from the heat underground. Desert mammals make more efficient use of their bodies’ water supply than does the human body. Reptiles are physiologically adapted to getting along with little water, and birds can fly to water sources when they need a drink. Nevertheless, the springs and seeps in the park are necessary to the survival of many animals.

Most of the reptiles and many small rodents and insects go into an inactive state of hibernation during the winter. However, winter is the time of greatest bird concentrations in the park, because of the presence of many migrant species.

A good place to view wildlife is at Barker Dam, a short hike from a parking area near Hidden Valley. Desert Bighorn Sheep and Mule Deer sometimes stop by the dam for a drink. Tours of the Barker Dam area are available.

Wildlife of the park includes:

• The California tree frog, Hyla cadaverina, is found in the rocky, permanent water sources created by the Pinto Fault along the northern edge of the park.
• The red-spotted toad, Bufo punctatus, is a true denizen of the desert, where it spends most of its life underground. Found from one end of the park to the other, it appears after good, soaking rains.
• Golden eagles hunt in the park regularly.
• The roadrunner is an easily recognized resident.
• The call of Gambel's Quail can frequently be heard.
• The tarantula Aphonopelma iodium, the green darner Anax junius, and the giant desert scorpion Hadrurus arizonensis are arthropods that can grow to be more than 4 inches (10 cm) long.
• The yucca moth Tegeticula paradoxa is responsible for pollinating the Joshua trees after which the park is named.

Wilderness

Of the park's total land area of 789,745 acres (319,598 ha), 429,690 acres (173,890 ha) are designated wilderness and managed by the National Park Service (NPS) in accordance with the Wilderness Act. The NPS requires registration for overnight camping at specific locations called registration boards. Other requirements include the use of a camp stove as open campfires are prohibited and employing Leave No Trace camping techniques (also known as "pack it in, pack it out"). Although bicycles are not allowed in wilderness areas, horses are, but a permit must be obtained in advance for travel in the backcountry.

Panoramic 360° view of Joshua Tree Park

Panorama of the view south from the popular Keys View in the Little San Bernardino Mountains, Joshua Tree National Park, California. Visible landmarks are the Salton Sea (230 ft/70 m below sea level) at rear left, along towards the center the Santa Rosa Mountains behind Indio and the San Jacinto Mountains behind Palm Springs. In the valley floor, the San Andreas Fault is clearly visible. At the rear right is the 11,500 ft (3,500 m) San Gorgonio Mountain.

See also

• Cahuilla
• Mojave and Colorado Deserts Biosphere Reserve
• National Register of Historic Places listings in Joshua Tree National Park

Notes

Teddy-bear cholla (Cylindropuntia bigelovii) at the Cholla Cactus Garden, Joshua Tree National Park

References

• Birds, Joshua Tree National Park Association
• California Desert Protection Act-1994, PDF document
• Joshua Tree: the Complete Guide: Joshua Tree National Park ISBN 978-0-9825172-3-9

External links

• Official website by the National Park Service
• Map of Joshua Tree National Park
• Geologic Travel Cuide: article by the American Geological Institute
• "Keys Ranch: Where Time Stood Still", a National Park Service Teaching with Historic Places (TwHP) lesson plan
• Joshua Tree National Park Bird Checklist with seasonal info.
• "Motorcycle Classics" Motorcycling through Joshua Tree National Park article