The dominant vegetation throughout is grasses and big sagebrush; however, there are meadows with cottonwood, aspen, and willow groves along some stream drainages.

The Pueblo Mountains in Harney County, Oregon, and Humboldt County, Nevada,[1] are part of the Basin and Range Province of the Western United States, which is characterized by a series of parallel fault blocks forming long north–south-oriented mountain ranges separated by wide, high-desert valleys.

This accounts for the relatively high elevation of the range's main ridgeline, which averages 7,300 feet (2,200 m) above sea level along its crest.

These older rocks are exposed along the range's east-facing escarpment and may be related to some of the Triassic formations of the Blue Mountains to the north.

[2][3][4] The southern part of the Pueblo Mountains has metamorphic rocks rich in quartz impregnated with gold, silver, and copper.

Common grass species include Idaho fescue, bluebunch wheatgrass, cheatgrass, Thurber's needlegrass, mountain brome, Sandberg's bluegrass, and bottlebrush squirreltail.

Meadow and high-desert wildflowers found in the Pueblo Mountains include larkspur, Indian paintbrush, cinquefoil, shooting star, columbines, monkey flower, asters, buttercups, low pussytoe, lupin, arrowleaf balsamroot, penstemon, agoseris, draba, mariposa lily, sego lilies, evening primrose, and iris.

Jackrabbits, antelope ground squirrels, bushy-tailed woodrats, and coyotes are common throughout the range, as are small-footed myotis bats.

There are also larger birds like golden eagles, red-tailed hawks, turkey vultures, and ravens that ride the thermals above the mountains.

The route is simply marked by rock cairns that serve as guideposts, allowing hikers to trek cross-country over the high-desert terrain from one marker to the next.

The cairns were built as a cooperative venture between the Bureau of Land Management, the Oregon Parks and Recreation Department, and the Desert Trail Association (a private organization).

The test equipment on the poles monitors weather conditions in the area to determine if winds would be strong and steady enough for commercial development.