Laboratory of Tree-Ring Research
West Stadium 214
office hours: T/TH 12-2

Research Interests

Over the past two decades, I have developed a variety of research interests, most of which can be broadly subsumed under the rubric of human/environment interaction and chronometry. I am interested in how human beings, as individuals, families, and suprafamily groups adapt to changing physical and social environments. Specifically, I am interested in the response of human groups to dynamic fluctuations in both their climatic and social environments. Dendrochronology has an important role to play in elucidating both the archaeological and paleoclimatic records, and can substantially enhance our understanding of these past human/environment interactions. Embedded in this approach are questions about the way humans distribute themselves across a landscape, the strategies and technologies they use to exploit their environment(s), their methods of interacting with their neighbors, and the techniques we can use to identify human/environment interactions in specific times and places.

My primary interest in the past few years has been investigating the ethnogenesis of the Navajo people. By using dendroarchaeological, dendroclimatological, material culture, settlement pattern, ethnographic, and historical data, as well as Navajo oral traditions, I have addressed questions concerning the Athapaskan entry into the Southwest, the development of the Navajo people as a distinct cultural group, the nature of intergroup relations in the northern

Southwest during the Protohistoric and early Historic periods, the early Navajo responses to environmental fluctuations, and the social and environmental pushes and pulls responsible for the Navajo abandonment of their Dinétah homeland. This is research that requires utilization of a variety of data types, and I consider it a very good example of the necessity of a multidisciplinary approach to research. Exploring the relationships between humans and their environments is predicated upon the analysis of high quality environmental and archaeological data. In the northern Southwest, both data sets are available for future research, and I envision expanding such research possibilities to other areas in the near future.

In methodological terms, I am interested in developing new methods of collecting dendrochronological samples from archaeological contexts. The first stage of this research has been quite successful on culturally modified trees near early Navajo sites, and I would like to expand it to other areas a well. Other areas where I am actively pursuing dendroarchaeological research opportunities are central Colorado and northern Mexico. I am very interested in documenting the aboriginal use of wood as a resource and would like to examine aboriginally peeled trees throughout the Northwest, Southwest, and Rocky Mountains. By demonstrating the utility of archaeological dendrochronology outside the Southwest, we will be able to use tree-ring data to explore human/environment interactions in a wider range of areas.

On a summer trip to northern Sonora led by Beth Bagwell of UNM, Chris Baker "rescues" the truck.  This area has tremendous potential for dendroarchaeological research that we hope to advance in the next few years.

Recent Publications

Towner, Ronald H.
in press The Navajo Abandonment of Dinétah. In The Protohistoric Period in the American Southwest, edited by D. Seymour. Utah State University Press, Logan.

Dykeman, D., R. H. Towner, and J. Feathers
in press Comparing Tree-Ring and Thermoluminescence Dating: Examples from Protohistoric and Early  Historic Period Navajo Sites. Paper acceptd for publiction in American Antiquity.

Towner, Ronad H., and Michael C. Clary
2001 Historical Dendroarchaeology in Central Colorado: Lessons form the Keystone Area.  Southwestern Lore 8-39.

Towner, R. H., H. C. Rogers, and J. M. Copeland
2001  Changing Threats, Changing Responses: Tactical Aspects of the Navajo Pueblitos of Dinétah. Tactical Sites in the American Southwest, edited by J. Welch and T. Bostwick, pp. 111-130.  Arizona Archaeologist No. 32. Phoenix.

Towner, Ronald, Dave Grow, June Psaltis, and Alice Falzone
2001  The Importance of Sample Context in Dendroarchaeological Interpretation: An Example from  Northwestern New Mexico, USA.  Tree-Ring Research 57:73-86.

Ababneh, Linah, Ronald H. Towner, Mary M. Prasciunas, and Karen T. Porter.
2001 The Dendrochronology of Palluche Canyon, Dinétah.  Kiva 66(2): 267-289.

Towner, Ronald H.
2000 Concordance and Conflict between Dendrochronology and Historical Records. In A History of Archaeological Dating in North America, edited by S. Nash, pp. 257-274. University of Utah Press.

Towner, Ronald H.
1999 The Navajo in Prehistory and History. In The Entangled Past: Integrating History and Archaeology. Papers of the 30th Chacmool Conference, Archaeological Association of Calgary, University of Calgary, Calgary AB.

Towner, Ronald H.
1999 Eighteenth Century Navajo Defensive Sites in the Dinétah. In Archaeology Southwest (Spring 8-9).

Towner, Ronald H., and Byron P. Johnson
1998 The San Rafael Survey: Reconstructing Eighteenth Century Navajo Population Dynamics in the Dinétah using Archaeological and Dendrochronological Data. Arizona State Museum Archaeological Series, No. 190. The University of Arizona, Tucson.

Towner, Ronald H., Leslie Sesler, and Tim Hovezak
1998 Navajo Culturally Modified Trees in the Dinétah. In Diné Bikeyah: Papers in Honor of David M. Brugge, edited by M. Duran and D. Kirkpatrick, pp. 195-209. Archaeological Society of New Mexico, Albuquerque.

Towner, Ronald H.
1997 The Dendrochronology of the Navajo Pueblitos of Dinétah. Ph.D. dissertation, Department of Anthropology, University of Arizona, Tucson. University Microfilms International, Ann Arbor.

Towner, Ronald H. (editor)
1996 The Archaeology of Navajo Origins. University of Utah Press, Salt Lake City, UT.

Towner, Ronald H.
1996 The Pueblito Phenomenon: A New Perspective on Post-Revolt Navajo Culture. In The Archaeology of Navajo Origins, edited by R.H. Towner, pp. 149-170. University of Utah Press, Salt Lake City, UT.

Towner, Ronald H., and Jeffrey S. Dean
1996 Questions and Problems in Pre-Ft. Sumner Navajo Archaeology. In The Archaeology of Navajo Origins, edited by R.H. Towner, pp. 1-18. University of Utah Press. Salt Lake City, UT.


I have taught a variety of courses at several institutions over the past decade. My most enjoyable, and recent courses include:

Introduction to Dendrochronology (Geos 464/564)

This is the primary course for students interested in dendrochronology at the Laboratory of Tree-Ring Research of the University of Arizona. The course gives students a solid grounding in the history, theory, and various applications of dendrochronology. It includes an intensive Lab component very ably taught by Mr. Rex Adams and Mr. Chris Baisan. At least one field trip collecting tree-ring samples for a specific research project is taken each year (research topic and location vary by year).

Tree-Ring Dating in Archaeology (Geos 595E)

This course provides students with an intensive exposure to the theory, methods, and practice of dendroarchaeology as conducted by faculty at the LTRR. We critically examine the literature of southwestern archaeological tree-ring dating. The week-long spring break field trip to the 4 Corners area is highlighted by the collection of samples from newly discovered archaeological sites. Students then prepare and date the samples in Tucson, present their results as a brown-bag lecture to the LTRR, and submit a paper to an appropriate journal.

Environmental History of the Southwest (Geos 220)

Team taught with Jeff Dean, Julio Betancourt, and Tom Swetnam (varies by semester). This course provides undergraduate students with a working knowledge of the past environmental variability of the American Southwest, and teaches them about the adaptations made by various human societies in the region (past and present).


1999-2002 Dendroarchaeology of the Navajo Occupation of the Southwest, P.I.: J.S. Dean, Co-P.I.: R. H. Towner; Agency: National Science Foundation; Amount: 270k; Duration: 7/00-7/03

1998-2000 Navajo Researvoir Paleoclimate, P.I.: R.H. Towner, Co-PI.: J.S. Dean; Agency: WCRM; Amount: 25k; Duration: 9/98-7/00

1996 Sigma Xi Travel Grant.

1996 Arizona Archaeological and Historical Society Research Grant (with Donn R. Grenda).

1996 Arizona Archaeology and Historical Society Travel Grant.

1995 Robert H. Lister Fellowship in Southwestern Archaeology. Crow Canyon Archaeological Center, Cortez, CO.

1994 AZ SHPO Matching Grant for San Pedro Trincheras Survey. Co-Principal Investigator with Jeffrey H. Altschul, Statistical Research, Tucson.

1993 NM SHPO Matching Grant for San Rafael Canyon Pueblito Survey. Co-Project Director with Byron Johnson, WCRM, Farmington.

1993 AZ SHPO Matching Grant for San Pedro Archaeological Project Survey. Co-Principal Investigator with Jeffrey H. Altschul, Statistical Research, Tucson.

1992 AZ SHPO Matching Grant for San Pedro Archaeological Project Survey. Co-Principal Investigator with Jeffrey H. Altschul, Statistical Research, Tucson.

1992 University of Arizona, Department of Anthropology Cummings Award

1992 University of Arizona Graduate College Research Grant

1991 Arizona Archaeological and Historical Society Scholarship

1991 Arizona Archaeological and Historical Society Research Grant

1991 Gilbert Altschul Fellowship, Statistical Research, Inc.