Dendrochronologia 32 (2014) 336–342 Contents lists available at ScienceDirect Dendrochronologia j ourna l h o mepa ge: www.elsevier.com/locate/dendro ORIGINAL ARTICLE Historical dendroarchaeology of two log structures in the Valles Caldera National Preserve, New Mexico, USA Kristen K. de Graauw a,* , Ronald H. Towner b , Henri D. Grissino-Mayer c , Nicholas V. Kessler b , Jonathan Knighton-Wisor d , Anastasia Steffen e,f , James P. Doerner g a Montane Forest Dynamics Laboratory, Department of Geology and Geography, West Virginia University, Morgantown, WV 26505, USA b Laboratory of Tree-Ring Research, The University of Arizona, Tucson, AZ 85721, USA c Laboratory of Tree-Ring Science, Department of Geography, The University of Tennessee, Knoxville, TN 37996, USA d Bryce Canyon National Park, Highway 63, Bryce Canyon, UT 84764, USA e Valles Caldera National Preserve, 90 Villa Louis Martin, Box 359, Jemez Springs, NM 87025, USA f Department of Anthropology, University of New Mexico, Albuquerque, NM 87131, USA g Department of Geography, University of Northern Colorado, Candelaria Hall 2096, Greeley, CO 80639, USA a r t i c l e i n f o Article history: Received 3 January 2014 Accepted 19 August 2014 Keywords: Historical dendroarchaeology New Mexico White fir Douglas-fir Partido system Baca Ranch a b s t r a c t We used dendroarchaeological techniques to determine the year of construction of two historic structures in the Valles Caldera National Preserve of New Mexico, USA. Historical documents date some structures in the headquarters area of the Preserve, but the Commissary Cabin and Salt Barn were lacking conclusive construction dates. Both structures were originally thought to have been built by the Otero family who bought the property in 1899. We found that the structures were built from two tree species, white fir (Abies concolor (Gordon) Lindl. ex Hildebr.) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), surprising given that ponderosa pines are also found in great numbers in the adjacent forest. Tree rings from 20 logs were confidently crossdated both graphically and statistically and provided cutting dates of trees in both structures of 1940 and 1941 when compared against the Fenton Lake reference chronology (Commissary Cabin: r = 0.69, t = 15.54, p < 0.0001, n = 263 years; Salt Barn: r = 0.77, t = 11.7, p < 0.0001, n = 232 years). By combining the cutting date years and terminal ring attributes, we suggest that both structures were built in the spring or early summer of 1941 using freshly cut logs and logs that had been cut the previous spring (1940, before or during the growing season) and stockpiled. The cutting dates of 1940 and 1941 indicate that these buildings were constructed during the Franklin Bond (1939–1945) era and associated with the transition from sheep ranching to more modern cattle grazing. These new dates provide a more distinct understanding of the cultural resources at the Valles Caldera National Preserve and provide interpretative staff with more accurate information that can be given to the public. © 2014 Elsevier GmbH. All rights reserved. Introduction Tree-ring dating of historic-period structures has a long history in Europe (c.f. Hillam, 1992; Baillie, 1995; Hillam and Groves, 1996; Hurni and Orcel, 1996). Dendroarchaeology has also often been applied to dating the years trees were harvested and subsequently used to build historic-period (post-AD 1600) structures in the east- ern US (Grissino-Mayer and van de Gevel, 2007; Harley et al., 2011; DeWeese et al., 2012; Grissino-Mayer et al., 2012; Therrell and Stahle, 2012). Numerous studies have also demonstrated that * Corresponding author. Tel.: +1 6784928111. E-mail address: kkdegraauw@mix.wvu.edu (K.K. de Graauw). early Euro-American settlement structures can be dated via tree rings in the American Southwest (e.g. Scantling, 1940; Ames, 1972; Robinson, 1985; Towner and Creasman, 2010). Such studies are discernibly fewer in number in the Southwest not because such structures are lacking, but because researchers have emphasized the importance of dating prehistoric rather than historic structures via tree-ring dating over the decades (Nash, 1999). Dendroar- chaeology is an important technique for verifying, confirming, and in some cases, refuting structure dates derived from docu- mentary or oral history sources. In addition dendroarchaeological research yields information on species selection, wood use and modification practices, and repair and remodeling episodes that are rare in documents or human memories (Dean, 1996; Towner, 2002). http://dx.doi.org/10.1016/j.dendro.2014.08.001 1125-7865/© 2014 Elsevier GmbH. All rights reserved.