Mojave National Preserve - Forests

One of the most distinguishing characteristics a forest is the presence of extensive tracts of trees, whether they be coniferous or deciduous. The leaves of conifers are modified into needles and are commonly called "evergreens" because they retain the needles throughout the entire year. Alternatively, deciduous or "broad-leaved" trees produce new paper-thin leaves each year. Because large amounts of water are necessary to produce the leaves of deciduous trees, conifers dominate in dry areas. Sunlight, soil, and elevation also contribute to determining the character of a forest. Although deciduous trees are found within Mojave National Preserve, the forests of the Preserve are strictly coniferous.

Of the two types of true forest found within the Preserve, pinyon-juniper woodlands are by far the most common. Extensive tracts of pinyon-juniper woodlands may easily be explored at the higher elevations found in the Mid Hills, New York Mountains, and Granite Mountains regions. Two types of pinyon pine, Colorado pinyon ( Pinus edulis ) and singleleaf pinyon ( P. monophylla ), and two types of juniper, California juniper ( Juniperus californica ) and Utah juniper ( J. osteosperma ) are present within the Preserve. Pinyon-juniper woodlands are common to the Great Basin desert, and big sagebrush ( Salvia dorii ), an indicator species of the Great Basin, abounds in the Mid Hills area. Pinyon jays ( Gymnorhinus cyanocephalus ) and rodents depend upon the seeds of the pinyon pine and are common denizens of the pinyon-juniper woodlands.

The New York Mountains and Clark Mountain are home to relict white fir ( Abies concolor ) forests found nowhere else in the Preserve. White fir need the slightly cooler temperatures and slightly higher precipitation amounts that these areas provide. As the name suggests, the needles are pale on both sides and distinctively flattened. Caruthers Canyon, a canyon in the rugged New York range, contains a particularly dense stand of fir. Interestingly, the white fir of Mojave National Preserve are more closely related genetically to the white fir of the Rocky Mountains than to those of the closer Sierra Nevada Mountains.

Although not a true tree, the Joshua tree ( Yucca brevifolia ) is a tall, tree-like yucca which grows in such high densities in some areas the resulting landscape resembles a forest. Joshua trees, which are endemic to the Mojave Desert, are found at the middle elevations within the Preserve (2,000 - 6,000 ft). The world"s largest and densest Joshua tree forest is located on Cima Dome, located west of Cima Road. Many species of desert shrub grow beneith the Joshua trees, including Mormon tea ( Ephedra sp.), a species which is related to conifers. Red-tailed hawk ( Buteo jamaicensis ), mourning dove ( Zenaida macroura ), and black-throated sparrow ( Amphispiza quinquestriata ) are some of the birds common to the Joshua tree woodlands, and signs of desert woodrat may be seen on the ground. The threatened desert tortoise ( Gopherus agassizii ) also calls the Joshua tree woodland home.