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An Archaeological Inventory in the Pike's Stockade Area, Conejos

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An Archaeological Inventory in the Pike’s Stockade Area, Conejos County, Colorado by Kevin D. Black Principal Investigator Colorado Historical Society with a contribution by Bruce Wahle Denver Chapter Colorado Archaeological Society Sponsored by Colorado Historical Society Office of the State Archaeologist of Colorado Program for Avocational Archaeological Certification Denver, Colorado Colorado State Permits #2004–21, 2005–6, 2006–41 October 2007 Abstract During the 2004–2006 field seasons, an archaeological survey was conducted east of Sanford, Colorado as part of the training available in the Program for Avocational Archaeological Certification (PAAC). The project thus used volunteers largely from the Colorado Archaeological Society (CAS) already enrolled in PAAC, supervised and trained by the Assistant State Archaeologist from the Colorado Historical Society. The inventory was completed on about 907 acres of the Pike’s Stockade State Historic Monument (PSSHM) in Conejos County, Colorado. The study tract encompassed a low shrubland environment on and around a volcanic mesa named Sierro del Ojito, bordering the wooded floodplain of the Conejos River, at elevations of 2,296–2,495 m. This area was intensively surveyed primarily to train PAAC volunteers in archaeological inventory and mapping methods. In addition, this portion of southern Colorado had been the subject of relatively little archaeological research interest, and the PSSHM—as a regional property of the Colorado Historical Society—made a logical choice for a PAAC survey project. As a result of the survey a total of 37 sites and 26 isolated finds (IFs) were recorded, including both American Indian and non-Indian materials. Historic period non-Indian sites comprise a rather diverse mix of artifact scatters, cairns, fences, stone enclosures, and rock inscriptions related primarily to ranching and recreational activities. The reconstructed Pike’s Stockade on the north side of the river is based on information in Pike’s journal, but no archaeological evidence for the February 1807 fortification has been found. Pre-Columbian sites are mainly open lithic scatters, hunting stations, and camps typically dating to the Archaic or Late Prehistoric periods. Limited evidence for more ancient Paleoindian period activity was found, post-dating 9300 BC. Common features include lithic artifact concentrations and fire- cracked rock (FCR) concentrations, and projectile points far outnumber other tool forms. More recent American Indian usage of the area such as by Ute or Jicarilla Apache groups was not recognized during the survey, but a few features of uncertain age may include this period. Lithic artifacts dominate in prehistoric assemblages; ceramic artifacts were entirely absent from these sites and IFs. Various colored cherts, jasper, basalt, and chalcedony were the commonly utilized toolstones, collected either locally or from sources none too distant from the southern San Luis Valley. Burial of archaeological materials is most likely to occur in aeolian and colluvial deposits at the northeast margin of the project area, south of the Conejos River, where surface site densities also are highest. Much sparser archaeological evidence was encountered on the mesa crest, and in the lower elevations south and west of the mesa, despite excellent ground visibility. Given that the entire project area is within easy reach of the river, prehistoric settlement patterns suggest that the presence of sand dunes exerted a notable attraction for early hunter-gatherer groups in the area. Overall, human occupation of the project area has been more localized than extensive, unlike some nearby areas such as the territory around the Great Sand Dunes to the northeast. A variety of additional work including test excavations, remote sensing, instrument mapping, tribal consultation, and archival research is recommended to evaluate the potential for intact buried remains in different site settings, and to more clearly assess site significance, should future developments threaten the physical integrity of these sites. Many pertinent research questions ii then could be addressed beyond the settlement data currently available, such as whether or not Paleoindian and Archaic remains lie buried beneath the dunes east of the mesa, if there is a Puebloan presence represented among the Late Prehistoric period resources, and what range of game animals were being hunted locally. The Pike’s Stockade State Historic Monument property was a useful training ground for PAAC. Not only is the land mostly well suited topographically for survey instruction, but the archaeological remains are quite diverse and locally abundant. Many of the volunteer participants have earned PAAC certificates using their experience in site recording at the PSSHM, and several others are nearing completion of the certification requirements. Table of Contents Page # Abstract..................................................................................................................................... ii Management Information Form.................................................................................................v List of Figures............................................................................................................................x List of Tables .......................................................................................................................... xii Acknowledgements................................................................................................................xiv Introduction................................................................................................................................1 Effective Environment...............................................................................................................4 Physiography and Topography .........................................................................................4 Climate and Paleoclimate .................................................................................................7 Geology and Toolstone Sources .......................................................................................8 Soils.................................................................................................................................12 Hydrology and Water Sources........................................................................................13 Flora and Fauna...............................................................................................................13 Environmental Constraints..............................................................................................14 Existing Data and Literature Review.......................................................................................16 Prehistoric Context..........................................................................................................18 Historic Context..............................................................................................................21 iii Table of Contents, continued Page # Statement of Objectives ...........................................................................................................28 Methods....................................................................................................................................29 Results......................................................................................................................................34 The Sites..........................................................................................................................35 Isolated Finds..................................................................................................................57 Site Types........................................................................................................................63 Features...........................................................................................................................69 Settlement Patterns..........................................................................................................70 Chronology and Cultural Affiliation...............................................................................73 Material Culture: The Lithic Landscape.........................................................................80 A Comment on Geoarchaeology.....................................................................................86 Evaluations and Recommendations .........................................................................................86 Summary and Conclusions ......................................................................................................92 References Cited ......................................................................................................................95 Appendix I, Project Area Map [under separate cover] ..........................................................111 Appendix II, OAHP Site and IF Forms [under separate cover].............................................113 Appendix III, Project Data Tables .........................................................................................114 Appendix IV, Spatial Analyses by Bruce Wahle...................................................................123 Appendix V, Portable XRF Analyses of Basalt and Obsidian Artifacts................................140 iv Colorado Office of Archaeology
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