Unit 37A

May Mountain and Red Point provide prominent high-country landmarks visible for navigation and glassing from distance. Goat Lake sits in the high basins and marks reliable water in the alpine country. Devils Basin anchors the upper terrain with its sprawling park-like terrain—a natural gathering point for high-elevation hunting.

Major drainages including McKim Creek, Mill Creek, North Fork Cow Creek, and Lake Fork serve as primary travel corridors and navigation aids through steep country. Graves Spring offers water access where reliable sources are scarce. These drainages funnel through narrow canyons and wide parks, creating distinct terrain zones that help you place yourself in big country.

Terrain spans from lower valley floors near 4,400 feet to windswept peaks above 11,300 feet, with most country sitting in the 7,000–9,500 foot zone. Low elevations along the river corridors feature open riparian areas and scattered timber that transition into dense conifer forests on the mid-slopes. Above 8,500 feet, forest opens into alpine meadows and exposed ridge systems where weather changes fast.

The median elevation of 7,635 feet puts much of the unit in productive transitional habitat—steep timbered draws leading up to basins and high ridges. This vertical compression creates diverse zones within short distances, though the steepness itself defines the character more than elevation bands.

Over 400 miles of roads provide surprising connectivity for a unit this steep, though road density numbers are masked by the vertical terrain. Roads concentrate in the lower drainages and river valleys; the high country is roadless and requires foot travel. Patterson and surrounding areas offer staging, and the connected road network means access points dot the unit perimeter.

However, the terrain complexity (8.1/10) filters pressure naturally—steep sidehills and drainage isolation discourage casual hunters. Early season and rut periods likely concentrate traffic in lower valleys and accessible drainages. Solitude exists for those willing to climb away from water sources and spend time above the road network.

Unit 37A encompasses the Salmon and Pahsimeroi River drainages in Custer and Lemhi Counties, anchored between these two major river systems that flow north through central Idaho. The unit's boundaries follow drainage divides, making the rivers themselves natural reference points for orientation. Patterson serves as the nearest settled area for resupply.

Most land is public, giving hunters broad access to the unit's remote interior, though the steep terrain itself limits easy travel. The drainage-based boundaries mean you're hunting country shaped by water rather than arbitrary lines—understanding these systems is critical to navigation.

Water scarcity is the dominant constraint here despite being mountain terrain. The Salmon and Pahsimeroi Rivers provide permanent water at low elevations, but mid-elevation draws dry quickly after spring runoff. Graves Spring and scattered high-mountain lakes like Goat Lake represent critical water sources, but neither is guaranteed year-round.

Drainages are the lifeblood—McKim Creek, Mill Creek, Mud Creek, and the North Fork systems carry water through the steeper terrain, but their flow varies seasonally. Most reliable water exists in the deepest drainages during early season; late-season hunting demands knowledge of specific springs or a willingness to pack water from the river bottoms. This limitation shapes where and when you can effectively hunt.

The steep drainages and moderate forest create a glassing-and-hiking unit rather than a vehicle-based operation. Early season offers the most flexibility—hunt high basins like Devils Basin and the slopes around May Mountain where visibility is best. Rut season concentrates activity in mid-elevation drainages where elk can move between high parks and lower timber.

Late season pushes game lower toward remaining water sources and unfrozen drainage bottoms. Key drainages like McKim, Mill, and Lake Fork deserve intensive scouting to locate reliable water and travel routes. The terrain rewards patience and fitness over tactics—vertical country like this punishes poor conditioning and rewards those willing to glass from distance and climb into isolated basins.

Species presence depends on current year conditions, but terrain suggests this is productive country for those equipped for steep, complex hunting.