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Florissant Summary


The Architectural Conservation Laboratory is actively involved in a unique project examining the feasibility of stabilizing large petrified stumps on the Petrified Forest Loop at Florissant Fossil Beds National Monument. In addition efforts are being made to establish long-term environmental monitoring at micro/macro scale to better inform the conservation and treatment plans.

Florissant Fossil Beds National monument is located in a high mountain valley about half a mile south of Florissant, Colorado. The monument is located west of Pikes Peak and 35 miles west of Colorado Springs, Colorado. The site is 6,278 acres, principally covering the Florissant Valley. Florissant’s recently built visitor complex (2012) houses an interpretive center and paleontological research laboratory. Older buildings nearby provide for the maintenance staff and serve as an archive. The petrified stumps constitute one of the major natural resources of the park. This project focuses on developing site-based methods for the conservation of petrified trees to benefit the park’s mission to conserve its fossil forest.

Of the nine stumps currently exhibited on the vistor trail, several display deterioration such as cracking, spalling and the loss of large fragments of petrified wood. This project addresses an urgent need for conservation by assessment and treatment evaluation for a heritage resource type that is under researched.

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All of the stumps were buried over time and have only been exposed for the past several decades. It is highly likely that the rate of deterioration of the stumps has increased significantly as a result of their exposure, however reburial is not a viable option.

While a first stage of research focuses on experimental remedial methods of stabilization and reintegration of detached material, the overall goal is to create a stable environment for the long-term preservation of the stumps in situ.  Available primary documentation and secondary literature relevant to the conservation of petrified wood and specifically the history of excavation, preservation, and display at Florissant was assembled on site. This coincided with an assessment of conditions contributing to material decay, as well as the compilation of an illustrated conditions glossary, and general stump survey.

Following  material characterization and analysis, an experimental dry  mechanical pinning system using rubber sleeves and threaded rod, was tested to address large scale loss and tabular detachment with minimal intervention.

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Many of the stumps have been banded with metal strapping in order to slow down the overall rate of decay. While the strapping has proven beneficial, it is visually disruptive and may be the cause of other added conditions.

Excavation and in situ presentation of Florissant stumps over the past 130 years have resulted in their continued deterioration including cracking, spalling, and loss that compromises the integrity of these important fossil specimens.
This research is supported by the National Park Service (NPS) through the Cooperative Ecosystem Studies Unit National Network (CESU) for the Colorado Plateau on behalf of Florissant Fossil Beds National Monument (alternatively referred to as either FLFO or Florissant) and the University of Pennsylvania’s Weitzman School of Design, Graduate Program in Historic Preservation and the Center for Architectural Conservation (CAC).
Stumps generally have three zones consisting of fragmentation, exfoliation and rising damp zones. Each of these zones impact the stump in unique ways resulting in different conditions. Conditions which represent effect can be used to better understand the causes of deterioration.
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