Western Wallflower (Erysimum capitatium)

A member of the mustard family, the Western Wallflower ( Erysimum capitatium ) is a brightly colored yellow flower which is quite common across the western United States, including Arizona, Utah and Nevada.. In European countries, the wallflower earned its name from a habit of growing on… you guess it, walls. More specifically stone, masonry or wooden fences. The name was transposed to the American species despite the fact the plants have no preference for walls.

Western Wallflower (Erysimum capitatium)
Western Wallflower (Erysimum capitatium)
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Pronghorn ( Antilocapra americana )

The pronghorn (Antilocapra americana), often mistakenly called an antelope, is the sole surviving member of the Antilocapridae family and North America’s fastest land mammal, capable of sustained speeds up to 55 mph (88 km/h). In the desert southwest of the United States, particularly the Sonoran Desert, the subspecies known as the Sonoran pronghorn (A. a. sonoriensis) exemplifies remarkable adaptations to arid environments, including efficient water conservation and heat tolerance. These graceful ungulates, with their distinctive pronged horns and white rump patches, roam vast open landscapes, evoking the untamed spirit of the American West.

A solitary Pronghorn ( Antilocapra americana ) found near Golbin Valley, Utah
A solitary Pronghorn ( Antilocapra americana ) found near Golbin Valley, Utah

Classification

Pronghorns belong to the kingdom Animalia, phylum Chordata, class Mammalia, order Artiodactyla (even-toed ungulates), family Antilocapridae, genus Antilocapra, and species americana. There are five recognized subspecies: the American pronghorn (A. a. americana), Mexican pronghorn (A. a. mexicana), Sonoran pronghorn (A. a. sonoriensis), Baja California pronghorn (A. a. peninsularis), and Oregon pronghorn (A. a. oregona). The Sonoran pronghorn, endemic to the desert southwest, is listed as endangered due to habitat fragmentation and human activities. Pronghorns are not true antelopes but are more closely related to giraffes and okapis, though they represent a unique evolutionary lineage that once included multiple species during the Pleistocene era.

Physical Description

Adult pronghorns measure 1.3–1.5 meters (4.3–4.9 feet) in length, stand 81–104 cm (32–41 inches) at the shoulder, and weigh 36–70 kg (79–154 pounds), with males typically larger than females. Their coat is tan to reddish-brown on the back and sides, with white underparts, throat, and distinctive white rump patches that flare as alarm signals. The namesake horns, present in both sexes but larger in males (up to 50 cm or 20 inches), are unique: they consist of a bony core sheathed in keratin that is shed annually, unlike true antlers or horns. Females’ horns are smaller and lack the forward-facing prong. Large eyes positioned on the sides of the head provide a 320-degree field of vision, aiding in predator detection, while long legs and cushioned hooves enable high-speed endurance running. Sonoran pronghorns are slightly smaller and lighter, adapted for desert life with enhanced heat dissipation through large ears and a slender build.

Behavior

Pronghorns are diurnal and crepuscular, most active at dawn and dusk to avoid midday heat in desert regions. They are highly social, forming mixed-sex herds of up to 1,000 individuals during winter migrations, but in the southwest deserts, groups are smaller (5–20) due to sparse resources. Territorial males defend harems during breeding, using scent marking from glands on the head and rump, and engage in ritualized displays like parallel walking or horn clashing. Their legendary speed—sprints up to 98 km/h (61 mph) and sustained 55 km/h (34 mph) over distances—evolved to outrun extinct predators like American cheetahs, and they can leap 6 meters (20 feet) horizontally. In the desert southwest, Sonoran pronghorns exhibit nomadic behavior, moving in response to rainfall and forage availability, and they pant or seek shade to thermoregulate in extreme heat. Communication includes visual signals like rump flashing, vocalizations such as snorts or bleats, and olfactory cues.

Food Sources

As herbivores, pronghorns are selective browsers and grazers, consuming a diverse diet of forbs (broad-leaved herbs), shrubs, grasses, and occasionally cacti, with preferences shifting seasonally. In the desert southwest, they favor drought-resistant plants like chainfruit cholla, mesquite, and palo verde for moisture, and can digest toxic species unpalatable to other ungulates due to large kidneys and specialized gut microbes. Forbs dominate in spring and summer (up to 90% of diet), while shrubs like sagebrush provide winter sustenance. They obtain most water from vegetation, drinking infrequently but traveling up to 10 km (6 miles) to water sources in arid areas. This opportunistic feeding helps them survive in low-productivity deserts, where they forage by nipping plants at ground level.

Breeding

Pronghorns are polygynous, with breeding (rut) occurring from July to October in southern populations like the Sonoran subspecies, timed to monsoon rains for optimal fawn survival. Males compete for females through displays and fights, establishing territories of 0.5–5 km² (0.2–2 sq mi). Gestation lasts 235–250 days, with females typically birthing twins (singles for first-time mothers) in secluded spots, hiding fawns in vegetation for the first few weeks. Fawns are precocial, standing within hours and running soon after, weaned by 4–5 months, and reaching sexual maturity at 15–16 months. In the desert southwest, breeding success is tied to rainfall; drought can lead to high fawn mortality from predation by coyotes or bobcats. Lifespan in the wild averages 10–15 years.

Habitat and Range

Pronghorns thrive in open, arid to semi-arid habitats with low vegetation for visibility, including grasslands, shrublands, and deserts at elevations from sea level to 3,300 meters (10,800 feet). In the desert southwest, the Sonoran pronghorn inhabits broad alluvial valleys, bajadas, and dry plains of the Sonoran Desert, separated by granite mountains, with sparse creosote bush, saguaro cacti, and ocotillo. Their range spans southwestern Arizona (e.g., Cabeza Prieta National Wildlife Refuge) and northwestern Sonora, Mexico, with a small population in California potentially extinct. Overall, pronghorns occur from southern Canada to northern Mexico, but in the U.S. southwest, they are found in Arizona, New Mexico, Nevada, Utah, and parts of California and Texas. They prefer gentle, rolling terrain for spotting predators from afar and avoid dense forests or steep mountains. Human developments like fences and roads fragment habitats, posing threats to migration and genetic diversity in desert populations.

Resources

Classification

Kingdom:Animalia
Phylum:Chordata
Class:Mammalia
Order:Artiodactyla
Family:Antilocapridae
Subfamily:Antilocaprinae
Tribe:Antilocaprini
Genus:Antilocapra
Ord, 1818
Species:A. americana[

Indian Paintbrush (Castilleja miniata)

The Giant Red Indian Paintbrush or Indian Paintbrush (Castilleja miniata) is a wildflower and perennial which is quite common in the western United States, including California, Nevada and Utah. The genus Castilleja contains about 200 species of hemiparasitic wildlowers.

Indian Paintbrush (Castilleja miniata)
Indian Paintbrush (Castilleja miniata)

The plant is known to grow between 1.5 and 3 feet tall and their stems may be unbranded of semi-branched. The flower cluster of the plant is said to resemble a paintbrush which gives the plant its common name. The bracts beneath the flower are known to be brightly colored and may be a bright orange, pink or a crimson red. Typically the paint brush will bloom May through Sepetember, however this event is subject to environmental conditions such as altitude and water availability.

The paint brush generally prefers sunlight and moist well drained soils. The root system will connect with and grow into the root system of other planets to harvest nutrients from the host plant. For this reason, they are no able to be transplanted easily.

Native American tribes are known to consume the edible flowers of the paintbrush. The selenium rich flowers were also used as a hair wash by the Ojibwe people. The Owls Clover is a member of the same genus as the Indian Paintbrush.

Wikipedia article of Castilleja.

Spreading Phlox ( Phlox diffusa )

Spreading Phlox ( Phlox diffusa ) is a perennial shrub with small needle like leaves.  This is a small white flowering plant prefers alpine, sub-alpine environments and rocky or sandy soil.  This is a low growing plant which is commonly only two to eight inches tall which probably offers survival advantages when confronted with the harsh landscapes of sub-alpine and alpine environments, in which it thrives.

Photographed in the White Moundtains, Phlox diffusa is a small white flowering plant which prefers alpine and sub-alpine environments.
Photographed in the White Moundtains in California Phlox diffusa is a small white flowering plant which prefers alpine and sub-alpine environments. Photograph by James L Rathbun

Spreading Phlox is commonly found and adapted high in the mountains and distributed throughout in the western United States and Canada. This plant employs a tap route, which is ideally suited to capture water deeper under ground and also offers an anchor to help the plant cling to the mountain in high wind conditions. The plant is short, and when in full bloom, the flowers may completely obscure the green needle like leaves from view.

The five petaled flowers range in color from a clean, magnificent white to calming understated lavender or pink color.  

The blooms are typically visible from May to August and a welcome sight to those who hike at elevation.