The Four Peaks form a prominent landmark visible from the eastern Phoenix metropolitan area. They rise from the southern end of the Mazatzal Mountains, a large and significant range in central Arizona. Among the four summits, only the northernmost, 7,659′ Brown’s Peak, carries a formal name. In this photo, Brown’s Peak is the farthest left of the quartet.
Montosa Canyon, on the western flanks of the Santa Rita Mountains, is an arid, brushy drainage facing the Santa Cruz Valley. In the foreground of the photo are a number of Clock-face Prickly Pear (Opuntia chlorotic).
Much of southwestern North America is in the immense physiographic region known as the Basin and Range Province. It is a landscape characterized by alternating north/south oriented mountains ranges and flat valleys. The photo is taken from a vantage point in the Santa Catalina Mountains. The right background is dominated by the nearby Rincon Mountains. To the left of the Rincons, a number of other mountain ranges can be seen, each ridge progressively farther away, all the way to the distant horizon.
A glimpse of the Gunnison River is seen here flowing through Black Canyon, captured in the gorge of its own making. At this location the nearly vertical cliffs are around 2,000′ high in Black Canyon of the Gunnison National Park, Colorado.
On the north rim of the Grand Canyon, the last rays of the setting sun cast a warm glow on the topmost white seam of the Kaibab and Toroweap formations of the canyon walls. Those same white layers can be seen in the buttes and temples that have become isolated from the rim through erosion.
Agaves are native to the Americas with their epicenter of diversity in Mexico. A number of species flourish in the southwestern United States. This variety, Parry’s Agave (Agave parryi) is distinctive with its compact and symmetrical form. It is also more cold tolerant than most agaves, able to survive temperatures down to about -5°F. These were photographed in the Gila National Forest, New Mexico at an elevation of about 6,700′ where it can get quite cold.
Happy Valley is a relatively undeveloped area on the east side of the Rincon Mountains, which is considered to be the “back” side of the range. The road to Happy Valley passes through desert grassland, open oak woodland, and occasional stream side habitat along the creeks flowing down from the higher elevations. These creek-side woodlands, called riparian woodlands, are the most ecologically complex of all, often supporting a number of hardwood tree species that would otherwise be unable to survive in this arid country.
Evening descends on the J-Six Ranch, Arizona. The 4,400′ elevation supports desert grassland, interspersed with yucca and mesquite.
The San Juan Mountains are a particularly steep range in southwest Colorado. Avalanches are frequent in this precipitous landscape and pose a serious threat to life and limb; so much so that the local authorities display this large avalanche advisory on the side of a building in Silverton. If you don’t mind delaying your visit until August, however, you will have one less thing to worry about.
In the Sonoran Desert, slope aspect is an important factor affecting plant communities. Slopes facing to the south are the most favorable sites for the diverse association of Sonoran Desert species. These frost-sensitive plants benefit from the abundant sunshine afforded by the southern exposure. This dense stand of Saguaro Cactus is indicative of the ideal conditions present on this south-facing bajada in the Santa Catalina Mountains, Arizona.