Encompassing an area of 1,234 square miles (3,196 square km), including 1,234 square miles (3,196 square km) designated as wilderness, Joshua Tree National Park, located in the east of Los Ange­les, USA, embraces parts of two distinct deserts, the higher Mojave Desert and the lower Colorado Desert, dividing the park into two arid ecosystems of profoundly contrasting appearance, mainly due to their differences is elevation. Initially established as a National Monument in 1936, the park was designated as a Biosphere Reserve in 1984, and ultimately declared as a National Park in 1994. As the name suggests, the park was named after the largest and the most iconic plant in the area, the Joshua trees, native to the Mojave Desert, which are also depicted by many as the canteen of the desert because its tissues hold water during dry spells.

Although its spiny leaves and thick bark protects the plant from being devoured by the thirsty animals, the living tissue of a Joshua tree is often the last source of moisture for animals during times of extreme drought. Nevertheless, it is apprehended that population of Joshua trees in the area could dramatically shrink in coming decades as a result of global warming. However, the park contains five desert fan palm oases, among which the Lost Palms Oasis, containing around 100 fan palms, is widely considered as the best.

The western part of the Joshua Tree National Park, with an elevation of above 3000 feet (900 m), and belonging to the Mojave Desert area, is warm and exceedingly dry during the summers, when day temperature often exceeds 38 C (100 F), and not cooling much below 24 C (75 F) until the early hours of the morning, but comfortable in the spring and fall, while winter brings cooler days, with temperature of around 16 C (60 F) with freezing nights..The dominant geologic features of the area are hills of bare rock, usually broken up into loose boulders. Due to low annual precipitation, which is only about 3-5 inches of rain annually, competition for survival in the area is tough for the plants and animals, and some plants like the Joshua trees evolved defensive mechanism like spikes.

In fact, the region is characterized by thousands of Joshua trees, with their unique and iconic appearance, complete with multiple arms ending in bunches of spiked leaves in patterns from dense forests to distantly spaced specimens. Other plants in the region include Pinyon or Piñon pine, Desert scrub oak, Tucker's oak, Muller's oak, California Juniper, and Chuckwalla Cholla.

The westernmost edge of the Colorado Desert, which is part of the Sonoran Desert, and runs with elevation of below 3000 feet (910 m), encompasses the eastern part of the Joshua Tree National Park, characterized by hotter temperatures, less rainfall, and wide-open spaces between mountain ranges. Compared to the western part, the eastern part of the park seems to be barren at first sight, mainly due to the absence of the gigantic Joshua trees. However, its flora includes several other plants, which include, among others, Desert Saltbush, Smoketree, Ocotillo and varieties of Cholla cactus, which thrive especially in the natural gardens, like the Cholla Cactus Garden and the Ocotillo Patch, which runs across arid Pinto Basin into a parched wilderness of broken rock in the Eagle and Coxcomb Mountains, located in the southeastern part of the park.

However, beginning as early as February, wildflowers grow abundantly throughout the park, creating a wonderful sight.

Wildlife in the park is diverse and relatively abundant, which include more than fifty species of mammals, forty five species of reptiles, and around 250 species of birds, many of whom are transitory guests during the spring and fall. Commonly found mammals in the park include desert Bighorn Sheep, Mule Deer, Foxes, Coyotes, also known as the American jackals, Bobcats, Jackrabbits, Bats and a wide variety of rodents, especially Kangaroo Rats. However, the animals in the park often have special adaptations for dealing with limited water and high summer temperatures. While some of the desert mammals use perspiration or panting as their main method of keeping cool, the smaller mammals and all reptiles take refuge from the heat underground. A few desert mammals, such as the round-tailed ground squirrels, sleep away the hottest part of the summer, and also hibernate in winter to avoid the extreme cold. The Reptiles in the park include lizards like, Geckos, Iguanas, and Skinks, along with the threatened Mojave Desert Tortoise that inhabits creosote bush lowlands in the Mojave Desert area. Snakes, especially several species of Rattlesnakes, and Scorpions are also found in the park. While Rattlesnakes consume rodents and small birds, Giant Hairy Scorpions have a diet consisting of insects, lizards and smaller scorpions.

The Oasis of Mara, including the 29 Palms Inn at the west end of the Joshua Tree National Park, is a good bird viewing area. While resident birds of prey include the Red-tailed Hawk, American Kestrel, Cooper’s Hawk, and Prairie Falcon, other bird species found in the park area are the Greater Roadrunner, Phainopepla, Cactus Wren, Rock Wren, Mourning Dove, Mockingbird, Verdin, Gambel’s Quail, and Le Conte’s Thrasher. Apart from that several migratory birds like the White-crowned Sparrow, Dark-eyed Junco, Sage Sparrow, Cedar Waxwing, American Robin, and Hermit Thrush appear in the park in the winter and stay till March, while another group, comprising species like Bendire’s Thrasher, Ash-throated Flycatcher, Western Kingbird, Scott’s Oriole, Northern Oriole, and Western Bluebird, begins to arrive for the spring and summer nesting season.

From the Visitor Centre, located outside the park, Park Boulevard leads to the Lost Horse Valley, from where three short interpretive trails, namely Hidden Valley, Barker Dam, and Cap Rock, invite the visitors to be introduced to the natural and human history of the Joshua Tree National Park. One of the two most favourite spots for the visitors, the eerie Skull Rock, a natural formation that looks like a skeleton’s head, is located along the main east-west Park Boulevard, and the other, the amazing Giant Marbles, formed by wind, rain, and sunshine, are tucked away in the southern part of Joshua Tree National Park, near the Cottonwood Spring. However, perhaps the most interesting thing is to observe the dark night sky, hanging over the park, which is far away from the urban area and largely free from light pollution, where the Central Milky Way can be seen in naked eyes, and Zodiacal light may also appear as a faint yellowish glow.