Cottonwood Spring: Petrified Wood Rockhounding in Malheur County, Oregon

Updated August 2026

Cottonwood Spring is a mapped rockhounding spot in Malheur County, Oregon. Reported finds include petrified wood. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Check locally
County: Malheur County
State: Oregon
Nearest road: Archie Myers Ranch Road
Coordinates: 42.02710, -117.92770

Geology at Cottonwood Spring

This spot sits on sedimentary rocks, mapped as tuff, fossils: mammalian vertebrate fossils, and tuffaceous sedimentary rocks that formed roughly 23 to 5 million years ago. Petrified wood typically comes from volcanic ash beds like the ones associated with this ground, where buried forests were slowly replaced by silica.

Mapped unit: sedimentary rocks
Age: 23–5 Ma (Miocene)
Rock types: tuff, fossils: mammalian vertebrate fossils, and tuffaceous sedimentary rocks
Elevation: 4,960 ft

Geologic mapping via Macrostrat and the underlying state geological survey maps (CC BY 4.0). Bedrock at the surface can vary within a mapped unit.

Best time to visit Cottonwood Spring

Best months: February to November. Typical highs run 90°F in midsummer and 39°F in midwinter, with winter lows near 16°F.

Climate normals: NOAA 1991-2020 monthlies, MCDERMITT station (11 mi away), adjusted for elevation.

Land & collecting status

Confirm rules before collecting

Land status here is not confirmed. Verify with the managing agency before collecting — federal, state, and tribal rules differ.

Public-land rules vary by agency, season, and field office. The RockHoundR app pulls live BLM, USFS, NPS, and tribal overlays so you can see exactly which agency manages the ground at this spot.

Sources & verification

Spot details combine the public RockHoundR location dataset, normalized mineral labels, agency land-status checks in the app, and community submissions. Coordinates are approximate until verified in the field.

State guidance last verified: April 1, 2026

BLM Oregon/Washington — Rockhounding & mineral material
Oregon Department of Geology and Mineral Industries (DOGAMI)
Oregon Parks and Recreation Department — beach collecting rules
Community submissions reviewed against published agency rules

Found at Cottonwood Spring

Each chip opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.

Petrified Wood Encyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Cottonwood Spring.

Across the state line from Cottonwood Spring

Cottonwood Spring is close enough to the Oregon border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Cottonwood Spring FAQ

Where is Cottonwood Spring?+

Cottonwood Spring is in Malheur County, Oregon, at 42.02710, -117.92770. Nearest road: Archie Myers Ranch Road.

What rocks and minerals can you find at Cottonwood Spring?+

Cottonwood Spring is reported to produce Petrified Wood.

Is collecting allowed at Cottonwood Spring?+

Confirm rules before collecting. Land status here is not confirmed. Verify with the managing agency before collecting — federal, state, and tribal rules differ. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Cottonwood Spring?+

A rock hammer, sturdy gloves, and a padded bag cover petrified wood hunting. Most pieces are surface float, so walking slopes and washes beats digging.

When is the best time to visit Cottonwood Spring?+

The most comfortable months at Cottonwood Spring are February to November.

How do I get to Cottonwood Spring?+

Open the directions link to navigate to 42.02710, -117.92770 in Google Maps. The nearest road is Archie Myers Ranch Road.

More rockhounding in Oregon

See all 177 Oregon spots →

Open Cottonwood Spring on the map

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