This area, which is on the Oregon border southwest of Boise and includes part of the Owyhee Mountains, is unusual because it lacks the extremely deep, rugged canyons that California bighorns inhabit in other sheep units.

Most hunters succeed in finding mature rams in this unit even though animals are more scattered than in some other sheep units.

The Owyhee Mountains and the Owyhee Desert are the main feature of this unit, which is along the Oregon Border south of Nampa, Caldwell and Kuna. Unlike most California bighorn sheep hunting areas in Idaho, Unit 40 doesn’t have extremely deep, rough canyons. The biggest canyon is Boulder Creek Canyon, which ranges from 300 to 500 feet deep and isn’t particularly rugged. The terrain is dominated by sagebrush steppes, juniper-covered hills and low mountains covered with conifers, such as pines and firs. High points includes 7,801-foot South Mountain, 8,051-foot War Eagle Mountain, 7,784-foot Florida Mountain and 8,403-foot Hayden Peak.

Sagebrush, greasewood, rabbitbrush, prickly pear cactus, wild grasses and low shrubs and forbs cover most of the low elevations. Juniper woodlands cover hundreds of square miles. Mahoganies, chokecherries, serviceberries and other bushes are scattered in pockets and on some ridges. High mountains have open ridges and forests of pines and firs with scattered aspen pockets. Cottonwoods and willows and brush grow along creek bottoms.

Road access is good to public land in this unit. Most of the land is controlled by the BLM. The state also holds some land in large and small tracts. The largest piece of state land is on Combination Ridge and stretches south to the unit’s southern boundary. Another big state area is near Rooster Comb Peak, which is southeast of a large private area. The largest private sector consists of farms and pastures along the Snake River in the north. Most roads are open to all vehicles. ATVs are restricted to designated routes in part of the unit and existing routes in other parts. A southern sector is closed to motor vehicles.

Hunters may camp along dirt roads almost anywhere on public land. The closest campgrounds to sheep country are private and county campgrounds along the northern boundary and a free primitive seven-site campground at Silver City. Canyon County operates Celebration Park Campground in Melba. Hunters can find lodging in many cities just north of the unit.