Layer reference
Every map layer — what it shows, where the data comes from, and what to watch for.
Every layer is built from a named open source with a recorded license — the full registry lives in data sources & licensing. This page is the field guide: what each layer means when you're planning a hunt.
Public land
Fee-simple ownership from USGS PAD-US 4.1 — every federal, state, and local manager, colored by agency. Clicking shows the unit name, manager, and the recorded public-access code.
PAD-US is updated roughly annually and aggregates state land office data; recently transferred parcels can lag.
Private parcels
Parcel boundaries with owner names, situs address, acreage, and county — where the source publishes them:
- Colorado — statewide composite from the Governor's OIT GIS team (~2.6M parcels, owner names, participating counties only).
- Wyoming — statewide parcels with owners.
- California — the hard case. No open statewide source with owner names exists, and the state's licensed composite can't be redistributed, so the hosted map carries county sources where counties publish owners (Mendocino, Humboldt, and the public-agency slice of Los Angeles), with more added as contributors submit them.
Owner names are public records from county assessors. Boundaries are assessor fabric, not survey-grade — treat lines near a fence as approximate.
Landlocked public land
Public land with no lawful route in: no public road contact and no chain of adjoining public parcels that reaches one. Computed by the pipeline from PAD-US and OpenStreetMap roads, with corner-crossing rules that follow the federal circuit the state sits in.
Advisory, not legal advice. Read how it's computed and where it errs before relying on it.
Hunt units
State wildlife agency boundaries, styled per state with the term hunters actually use:
| State | Layer | Source |
|---|---|---|
| Colorado | GMUs | Colorado Parks & Wildlife |
| Wyoming | Elk hunt areas | Wyoming Game & Fish |
| California | Deer zones (A/B/C/D/X) | CDFW BIOS |
California's zone geometry is CDFW's 2014 vintage and explicitly approximate — the regulation text (Title 14) controls, not the line on any map.
Walk-in access
Programs that open private or state land to public hunting:
- Colorado — CPW Walk-In Access properties (seasonal leases; identify shows cover type and closing date).
- California — CDFW Public Access Lands (state-owned wildlife areas and ecological reserves). California's SHARE walk-in program publishes no spatial data at all, so it can't be mapped.
Slope and aspect
Computed from USGS 3DEP elevation at 30 m. Slope is classed for stalk planning and avalanche awareness; aspect shows which faces hold snow, feed, or bedding sun. Slope is computed on the geographic DEM before Web Mercator reprojection — doing it after would overstate slope at northern latitudes.
Trails and motorized routes
- Trails — Colorado uses COTREX (the state's trail inventory); Wyoming and California use OpenStreetMap trails.
- MVUM — US Forest Service Motor Vehicle Use Maps: the legal motorized routes, styled by what you may drive. Solid warm lines are roads open to all vehicles (ATV/UTV legal); solid grey means street-legal vehicles only; dashed lines are OHV and motorcycle trails; amber ticks alongside a route mark a seasonal closure. Tap any route for its designation, the vehicle classes allowed, and its season status. If a road isn't on the MVUM, it isn't legal to drive on Forest Service land — this layer is the difference between a shortcut and a citation.