Petrified wood is a three-dimensional fossil where the original organic material has been completely replaced by minerals. This process, called permineralization, occurs when wood is buried by water-saturated sediment or volcanic ash, preventing decay. Mineral-rich groundwater, often containing silica, seeps into the wood’s cellular structure, crystallizing over millions of years to form quartz, agate, or opal. Utah is a prime location due to the Late Triassic Chinle Formation, which preserves remnants of a subtropical forest that grew here approximately 225 million years ago.
Understanding Collection Regulations in Utah
Collection rules depend on whether the land is managed federally by the Bureau of Land Management (BLM) or by the state’s School and Institutional Trust Lands Administration (SITLA). Most accessible petrified wood is found on BLM public lands, which allow for casual collection without a permit for personal use. Collection is limited to 25 pounds plus one piece per person daily, capped at 250 pounds annually. The collected material cannot be sold, traded, or bartered for commercial purposes.
Collecting on state-managed SITLA lands requires a general rockhounding permit, which typically involves a fee. Once secured, the same weight limits apply. For all public lands, collection must use only hand tools; motorized equipment, explosives, or power tools are prohibited. It is prudent to contact the local BLM or SITLA field office before searching, as local restrictions can vary.
Key Public Lands for Rockhounding
Productive areas for petrified wood collection are located in the vast stretches of BLM land in southeastern Utah. The areas surrounding Hanksville are well-known for yielding specimens from the Chinle Formation. Rockhounds often explore the remote desert terrain off Utah Highway 24, especially west of Caineville, where agate and petrified wood fragments are scattered on the hill slopes.
The Andy Miller Flats area, south of Hanksville near the Glen Canyon National Recreation Area boundary, is a remote but rewarding location. This region often requires a high-clearance or four-wheel-drive vehicle due to the rough dirt roads. Collectors must stay north of the Glen Canyon National Recreation Area boundary line to remain on legally accessible BLM land. Another region to explore is the BLM land near the Virgin Anticline in southwestern Utah, close to Hurricane, where high-quality Triassic-aged specimens have been documented.
Protected Areas Where Collection Is Forbidden
Utah is rich in geological sites, but numerous areas are legally closed to all forms of collection. All federally designated National Parks (such as Zion, Capitol Reef, and Bryce Canyon) strictly prohibit the removal of any natural resources, including petrified wood. Similarly, National Monuments, including Grand Staircase-Escalante, are protected areas where materials cannot be collected.
The Wolverine Petrified Wood Natural Area, a specific section within Grand Staircase-Escalante, contains a significant concentration of Triassic logs but is entirely off-limits. State Parks, like the Escalante Petrified Forest State Park, also prohibit the removal of petrified wood. Removing any natural object from these protected areas can result in substantial fines and is a serious offense.
Practical Tips for Finding and Identifying Petrified Wood
Petrified wood is much denser and heavier than non-fossilized wood, and its surface feels like stone. The most telling characteristic is the preservation of wood grain, tree rings, or bark texture, even though the material is now a form of quartz or agate. Coloration indicates the trace elements present during mineralization; iron oxides create reds and browns, while copper or chromium often result in shades of blue and green.
Search in areas where erosion has exposed ancient geological layers, such as dry washes, arroyos, or eroded hillsides. Since surface collection is preferred, look for fragments naturally weathered out of the surrounding sediment and lying on the ground. Ethical collection means disturbing the environment as little as possible, which includes refraining from digging large holes or using power tools. Always carry plenty of water, wear sun protection, and consider safety glasses along with a small rock hammer or chisel for basic investigation.