GMU 421 GMU 421 — Mesa/Garfield Co.
A top OTC Grand Mesa elk unit — big timber, big herd, general-season bull tags
West-central Colorado — Mesa & Garfield Counties (eastern Grand Mesa) · Last reviewed 2026-07-12
Area
542
sq mi
Public land
65%
approx.
Elevation
4,800–11,000
feet
Motorized
extensive
access
Overview
GMU 421 is a roughly 542-square-mile unit covering the eastern shoulder of the Grand Mesa, bounded on the north by the Colorado River–Plateau Creek divide, on the east by the Divide Creek–Buzzard Creek divide, on the south by the Mesa–Delta county line, and on the west by Colorado Highway 65. It is a core piece of the Grand Mesa elk herd (units 41, 42, 421) and consistently ranks among Colorado's top over-the-counter units for both 2nd and 3rd rifle bull harvest and hunter success — this is a high-volume general-season elk unit, not a limited trophy draw. Elk carry a large annual harvest (roughly 540) at OTC-level success. Mule deer is fully limited-draw and the more selective hunt; pronghorn is a token, incidental presence.
Terrain
Classic Grand Mesa terrain — a broad, timbered high plateau climbing from low pinyon-juniper benches to spruce-fir and lake-dotted forest above 10,000 feet. Steep drainages (Divide Creek, Buzzard Creek, Plateau Creek) cut off the mesa toward the Colorado River, and oakbrush blankets the mid slopes.
Cover: Pinyon-juniper and sage-oakbrush low, dense Gambel oak and aspen through the mid elevations, and heavy spruce-fir and dark timber with meadows and lakes on the high mesa top.
Landmarks: Grand Mesa (eastern top) · Colorado Highway 65 / Grand Mesa Scenic Byway · Divide Creek · Buzzard Creek · Plateau Creek · Mesa Lakes / high-mesa lake country · Grand Mesa National Forest
Access
The high mesa is extensive Grand Mesa National Forest with good road access off Colorado 65 (the Grand Mesa Scenic Byway) and connecting forest roads, plus BLM on the mid-elevation benches. The lower drainages and the Plateau Creek / Colorado River valley edge hold private ranch ground. Colorado State Trust lands are NOT open to hunting unless enrolled in CPW's Public Access Program — do not treat them as huntable. Access is easy by west-slope standards, which is exactly why the OTC pressure is real.
Managers: USFS Grand Mesa National Forest, BLM Grand Junction / Colorado River Valley Field Office, private ranch
Access points: Colorado Highway 65 / Grand Mesa Scenic Byway · Grand Mesa NF road system off the byway · County roads up Plateau Creek from the north · Divide Creek / Buzzard Creek drainage roads
Species notes
Rocky Mountain Elk
abundant opportunityThe headliner and a genuine OTC standout — GMU 421 ranks among the top units for both 2nd and 3rd rifle bull harvest and success in Colorado, with a large annual take (~540). Over-the-counter bull tags make it a high-value general-season unit, though success runs at OTC levels (low-to-mid teens).
- →Work the dark spruce-fir and aspen edges and oakbrush pockets of the high mesa in early seasons; the rut can fire the first week of September and run a month.
- →By 2nd and 3rd rifle, hunt the migration — elk drop off the top into the oakbrush and lower drainages ahead of snow, so position on travel corridors between the high timber and lower benches.
- →Get off Highway 65 and the main forest roads; the pressure is heaviest near the byway.
Mule Deer
common qualityFully limited-draw and the more selective hunt, with decent success (recent tags filling around 40%). The best deer hunting is the mid-elevation oakbrush and aspen (roughly 8,500–9,500 ft), with better bucks showing in later seasons.
- →Glass the oakbrush-aspen mid-elevation transition rather than the high timber or the low pinyon.
- →Hunt later seasons for bigger bucks as deer concentrate on the move to winter range.
- →Use high vantage points and optics — this is glass-and-stalk country.
Pronghorn
transient lowA token, incidental presence — only a couple of animals in recent harvest off a stray tag. GMU 421 is not a pronghorn destination.
- →Look to the open lower benches and sage margins, not the timbered mesa.
- →Treat any tag as a bonus paired with elk or deer hunting.
Black Bear
common opportunityStrong black bear habitat in the Grand Mesa oakbrush and serviceberry — a good add-on tag, best in years with a heavy mast and berry crop.
- →Target Gambel oak and serviceberry benches when the fall food comes on.
- →Glass south-facing brush pockets at first and last light for feeding bears.
- →Overlap with an archery elk hunt for the best chance.
Pro tips
- →GMU 421 is one of Colorado's top OTC 2nd/3rd rifle bull units — a high-value general-season elk tag.
- →The limited-draw mule deer is the more selective, trophy-leaning hunt.
- →Get well off the Grand Mesa Scenic Byway (Highway 65) to escape the OTC crowds.
- →Hunt the migration in late seasons — position between the high timber and lower oakbrush as snow pushes elk down.
- →Carry an ownership map to stay off the private drainages on the unit's lower edges.
Watch out for
- !Colorado State Trust lands are not open to hunting unless enrolled in CPW's Public Access Program.
- !OTC rifle crowding concentrated near Highway 65 and the main forest roads.
- !Private ranch ground on the lower Plateau Creek / Divide Creek / Buzzard Creek edges.
- !Early snow can close high-mesa forest roads.
- !Late-summer fire risk in the oakbrush and timber.
Logistics
Collbran and Mesa are the closest small towns, with Palisade and Grand Junction to the west as the full-service hubs for fuel, groceries, lodging and repair. Colorado Highway 65 (the Grand Mesa Scenic Byway) is the spine of the unit and makes access easy — which cuts both ways, since it also draws OTC crowds. Plan for high-elevation camping, cold late-season weather, and forest roads that turn to mud and snow quickly on the mesa top. A good ownership map keeps you off the private drainages on the lower edges.
Nearest towns: Collbran, CO, Mesa, CO, Palisade, CO, Grand Junction, CO
Seasons & regulations
This page carries no season dates or regulations. Get current rules from the official Colorado sources:
Research sources: CPW Big Game Hunting · HuntScore — Colorado GMU 421 (Mesa & Garfield Counties) · Backcountry Chronicles — Colorado OTC Elk Units (2nd/3rd rifle top performers) · Horn and Fin — Colorado Elk & Mule Deer DIY Hunts GMU 421
FAQ
- How big is GMU 421 in Colorado?
- GMU 421 (GMU 421 — Mesa/Garfield Co.) covers about 542 square miles, ranging from roughly 4,800 to 11,000 feet in elevation. Area is computed from the unit boundary polygon.
- How much public land is in GMU 421?
- Approximately 65% of the unit is public land. Primary managers: USFS Grand Mesa National Forest, BLM Grand Junction / Colorado River Valley Field Office, private ranch. Always verify ownership boundaries on the ground.
- What species does the catalog list for GMU 421?
- Rocky Mountain Elk, Mule Deer, Pronghorn, Black Bear. For seasons, tags, and regulations, use the official Colorado agency resources linked on this page — this page carries no regulatory information.
Put GMU 421 on your map.
Boundary lines, public/private ownership, topo, and offline maps for this unit — in Baseline Maps, free for 14 days.