Dendrite Butte: Limb Casts & Opalized Wood Rockhounding in Crook County, Oregon

Updated August 2026

Dendrite Butte is a mapped rockhounding spot in Crook County, Oregon. Reported finds include limb casts, opalized wood, petrified wood. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Check locally
County: Crook County
State: Oregon
Coordinates: 44.02284, -120.05908

Geology at Dendrite Butte

This spot sits on John Day/Clarno Group; Clarno Formation, mapped as mudflow breccia that formed roughly 56 to 23 million years ago. Sedimentary beds like these are the typical host for petrified and silicified wood, which weathers out as durable float on slopes and in washes.

Mapped unit: John Day/Clarno Group; Clarno Formation
Age: 56–23 Ma (Eocene to Oligocene)
Rock types: mudflow breccia
Elevation: 4,430 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 Dendrite Butte

Best months: March to November. Typical highs run 86°F in midsummer and 39°F in midwinter, with winter lows near 18°F.

Climate normals: NOAA 1991-2020 monthlies, PAULINA station (8 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 Dendrite Butte

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

Nearby rockhounding spots

Other rockhounding spots within driving distance of Dendrite Butte.

Dendrite Butte FAQ

Where is Dendrite Butte?+

Dendrite Butte is in Crook County, Oregon, at 44.02284, -120.05908.

What rocks and minerals can you find at Dendrite Butte?+

Dendrite Butte is reported to produce Limb Casts, Opalized Wood, Petrified Wood.

Is collecting allowed at Dendrite Butte?+

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 Dendrite Butte?+

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 Dendrite Butte?+

The most comfortable months at Dendrite Butte are March to November.

How do I get to Dendrite Butte?+

Open the directions link to navigate to 44.02284, -120.05908 in Google Maps. Some spots are remote, so check road conditions before driving out.

More rockhounding in Oregon

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Open Dendrite Butte on the map

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