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2008 Abstracts

Joint Annual Meeting of the Geological Society of America, American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America (Houston, Texas; October 2008)

Geochemical and Soil Micromorphological Properties of Archaeological Deposits in Coastal Southern California

Jeffrey A. Homburg1,4, Richard I. Macphail2, Paul Goldberg3, and James H. Mayer4
1Statistical Research, Inc.; 2University College of London, United Kingdom; 3Boston University; 4University of Arizona

Geoarchaeological and soil studies were conducted in Los Angeles as part of the Playa Vista Archaeological and Historical Project prior to development of property formerly owned by Howard Hughes. Field investigations at CA-LAN-62 and other ancient settlements near the Ballona Lagoon and surrounding wetlands were completed to aid in interpreting the formation, preservation, and alteration of cultural deposits on alluvial fans along the base of the Ballona Escarpment. These settlements span the last 6,000+ years, with sites represented by Mission period through Millingstone period occupations. A variety of soil analyses were completed (e.g., pH, organic matter, nitrogen, calcium carbonate, electrical conductivity, particle-size, and bulk density analyses), but phosphorus analysis proved especially useful. Phosphorus concentrations were used to identify buried occupation surfaces that were not always visible macroscopically in the surficial and buried soils. Phosphorus analysis was also used to discern ancient activity areas in relation to cultural features represented by food processing, cooking, refuse disposal, and other activities. Micromorphological analysis of fire hearths revealed use of peat that may have served as fuel, lagoonal clay for hearth construction on sandy substrates, and coprolites from large scavenging animals, as well as the identification of egg shells and other materials not documented by other archaeological recovery methods. Soil micromorphology was used to identify alterations of cultural deposits, such as those caused by groundwater fluctuations marked by calcitic hypocoatings and redoximorphic features, burial by fan/alluvial deposits, and reworking of deposits by bioturbation.

Soil Properties of an Ancient Dryland Agricultural Complex in Central Arizona

Robert M. Wegener1 and Jeffrey A. Homburg1,2
1Statistical Research, Inc.; 2University of Arizona

Prehistoric dryland agricultural soils were investigated near Queen Creek in central Arizona as part of the U.S. 60 Archaeological Project. This study aimed to (1) determine the long-term effects of cultivation and agricultural management practices on soil quality, (2) measure the effects of rock mulch on unsaturated hydraulic conductivity, and (3) compare the results with previous soil studies of ancient agricultural systems in the region. A suite of physical and chemical soil tests were used to compare the soil properties associated with terraces, rock alignments, and rock piles to uncultivated control soils from similar soils and landscape positions. Justification for this type of study is provided by the following factors: (1) soil formation is slow in semiarid climates, so cultivation effects persist for centuries to millennia; (2) many ancient fields have remained uncultivated since they were abandoned, so long-term soil properties reflect ancient agricultural use; (3) agricultural features provide clues for identifying and sampling ancient cultivated and control soils; and (4) ancient farming systems are relevant to modern studies of agricultural sustainability. Results of this study indicate that cultivation and management practices improved soil quality in agricultural contexts relative to the controls. Rock mulch soils tend to have elevated organic carbon, nitrogen, and total and available phosphorus levels, with reduced or no changes in soil pH. Bulk density tests showed that cultivation has not caused soil compaction. Salinity is elevated in some agricultural contexts but not at levels detrimental to crop growth. Rock mulch soils have higher unsaturated hydraulic conductivities than uncultivated controls. Overall soil fertility and productivity is improved in the cultivated soils, which is similar to previous studies of ancient agricultural studies in the middle Gila and lower Verde River valleys of Arizona.

Fall 2008 Arizona Archaeological Council Conference: Advances in Hohokam Archaeology (Phoenix, Arizona; October  2008)

Pre-Hispanic Food Production and Social Relations at the Cashion Site Complex:  Settlement and Subsistence during the Early Archaic and the Hohokam Pre-Classic Periods

William M. Graves, Robert M. Wegener, and Richard Ciolek-Torrello

Recent work at AZ T:11:94 (ASM), located just south of the Cashion Site Complex, near the confluence of the Salt and Gila Rivers, provides a wealth of information concerning the human use of the Salt River floodplain in the western Phoenix Basin from, perhaps, the Early Archaic period and the Hohokam pre-Classic period. A possible Early Archaic structure and pits provide information concerning settlement and the subsistence activities in which people were engaged during this early period of time. Later, pre-Classic field houses, pits, and a possible canal document the use of the floodplain by residents of the Cashion Site Complex. We use the information we have gathered from Site 94 to discuss more general patterns in the Prehispanic use of the floodplain by Early Archaic hunter-gatherers and by Hohokam irrigation agriculturists and the kinds of social relations and cultural connections in which residents of the western Phoenix Basin were engaged.

14th Annual Conference of the European Association of Archaeologists (Velletta, Malta; September 2008)

Hohokam Settlement in the Mountains and River Valleys of the American Southwest

Richard Ciolek-Torrello, Robert M. Wegener, and Jeffrey A. Homburg

The Hohokam Indians are well known for developing the largest and most-complex irrigation system in the deserts of the New World. But this is only a part of the story.
The Gila and Salt Rivers that the Hohokam tapped to supply their canals flow from high mountains, which reach over 3,500 m and bound the deserts areas on the north and east. In the first millennium of their existence, the Hohokam exploited the deserts and these surrounding mountains. They built their canals and towns in the floodplains of the rivers together with smaller villages in the mountains, where they farmed along the tributaries of the Salt and Gila Rivers and hunted wild game. With very limited areas for traditional farming practices, the mountain Hohokam also developed new strategies for dry farming and developed new domesticates, most importantly a succulent known as agave that could be grown in thin, rocky mountain soils. The mountain Hohokam were closely tied to the desert Hohokam through a network of ceremonial exchange focused on ballcourts and a cremation mortuary complex. This close integration was necessary, because of uncertainties in food production in both regions. Farming in the floodplains of the larger river valleys was often tenuous because of cycles of flood and drought, whereas mountain farmers did not have enough arable land to sustain themselves.

Around A.D. 1000, circumstances changed as a millennium of floodplain stability changed. The floodplains of the Salt and Gila River were eroded and downcut, destroying canals, fields, and riparian forests that provided fuel, building materials, and animal products. The desert Hohokam responded to these changing environmental circumstances by building new canals on higher terraces overlooking the floodplains.

This response resulted in opening vast new acreage to agricultural production in areas that were much less prone to flooding and erosion. Hohokam population and house construction expanded tremendously in the major river valleys. At the same time, mountain settlements were abandoned and many of their residents moved to the valleys, where they were incorporated into the growing settlements. They brought with them, however, the agave and dry-farming technologies they had developed in the mountains and built large dry-farming systems in the rocky hills surrounding valley towns. The old ballcourt system, which had integrated settlements throughout a vast region of the Southwest, was replaced by a new sociopolitical system that focused on the large desert towns along the Salt and Gila Rivers. Able to sustain themselves entirely on the production of their expanded canal system and nearby dry-farming fields, the Hohokam cut their ties to the neighboring mountain areas, a gap into which poured independent and often hostile groups of people.

2008 Annual Meeting of the Society for California Archeology (Burbank, California; April 2008)

Expedientes, Padrones, Flaked Stone, and Cattle Bones: Ethnohistoric Research, Archaeological Data, and Future Directions for Mission Period Archaeology near the Ballona Lagoon
Note: From the symposium “Ethnohistoric Research and Colonial Period Archaeology in Southern California,” chaired by John R. Johnson

Benjamin R. Vargas

In southern California, historical documents and archaeological data are often intertwined to create models of prehistoric behavior. New archival research and recent archaeological investigations by Statistical Research, Inc., are allowing us to evaluate past models of human interaction created for work near the Ballona Lagoon. A continuation of traditional practices in ritual contexts and an incorporation of introduced materials in domestic contexts is an emerging pattern at these sites. In this paper, archaeological materials are contrasted with ethnohistoric data to evaluate Native American interactions with the Mission San Gabriel, the pueblo of Los Angeles, and/or local Hispanic ranchos.

73rd Annual Meeting of the Society of American Archaeology (Vancouver, Brisith Columbia; March 2008)

Late Archaic, Early Agricultural, Early Ceramic Period Architecture in Southern Arizona

Richard Ciolek-Torrello, Robert M. Wegener, and Heather Miljour

Our research involved 45 completely excavated Cienega and Red Mountain phase structures dating between 900 B.C. and A.D. 400. Significant variation in the construction of the superstructures, hearths, entries, and number and type of intramural pits was documented among structures dating to each phase. Using this variation, we identified preliminary morphological and functional categories.We also compare them to Cienega, Agua Caliente, and Tortolita phase architecture in the Tucson Basin and at the Kearny site along the Gila River. We conclude with how this architectural variability can be used to understand the forager-farmer transition in southern Arizona.

Ceramic Technology of the Forager-Farmer Transition: Late Archaic and Early Agricultural Pottery of Southern Arizona

Robert A. Heckman, Christopher P. Garraty, and Resha Shenandoah

Excavation of several Cienega and Red Mountain phase site components resulted in the collection of over 3,500 sherds from nonriverine habitation loci in the Queen Creek region. This collection allowed a detailed examination of the beginnings and development of well-fired ceramic container technology in southern Arizona. Our preliminary findings concerning vessel manufacture and function are compared to previous studies at sites along the Gila and Middle Santa Cruz Rivers, along with a cross-cultural comparison with protohistoric and historical-period forager-farmer groups. The results shed light on the transition from multiuse vessels to an increasingly specialized ceramic container technology.

Hunting Practices and Faunal Subsistence Patterns during the Forager-Farmer Transition in Southern Arizona

Janet Griffitts and Jennifer A. Waters

Excavations at Finch Camp (AZ U:11:7 [ASM]) produced one of the largest and best-dated nonriverine Cienega and Red Mountain phase faunal collections recovered from the Queen Creek region. Leporid and artiodactyl remains dominate the faunal assemblage, and many rodent taxa are also represented. Comparable faunal collections have been recovered from contemporary, riverine contexts in the Tucson Basin. The Finch Camp fauna allow a detailed reconstruction of subsistence and hunting strategies in the Queen Creek region, along with comparison of hunting and subsistence in riverine and nonriverine settings during the forager-farmer transition in southern Arizona.

U.S. 60 Symposium

As part of an Arizona Department of Transportation–sponsored project, Statistical Research, Inc., excavated 13 prehistoric sites situated along U.S. 60 between Florence Junction and Superior , Arizona, in 2005–2006. Included among these sites were habitation loci representing 3,000 years of aboriginal occupation. An unprecedented result of the project was the discovery of nonriverine Late Archaic/Early Agricultural settlements represented by securely dated house groups, human burials, and extramural facilities. We discuss our findings to date, focusing on Cienega (800 B.C.~A.D. 1) and Red Mountain (A.D. 1–400) phase land use, technology, agriculture, mortuary practices, and chronology.

From Basin to Rim: Foraging and Farming Landscapes in South-Central Arizona

Michael Heilen

The U.S. 60 project resulted in the discovery of habitation and limited-activity site components dating from 900 B.C. through A.D. 1450, including ancient agricultural habitation sites in nonriverine settings. Focusing on these early sites, we compared the landscape context of US 60 sites to over 1,500 sites in an approximately 4,500 km2 area of south-central Arizona. In this paper, the emergence and development of forager-farmer land-use strategies is modeled by tracking variability and change through time in site location and composition. This information is used to infer the systemic landscape context of the U.S. 60 sites.

The Content of Feature Fill and Changes in Domestic Activities at Sites in the Queen Creek Valley

William M. Graves

Excavations at seven sites have yielded a wealth of data concerning trash deposition and the character of feature fill in contexts dating from the Early Agricultural period through the pre-Classic period. These data allow us to examine issues concerning the nature of settlement and community throughout this long period. In this paper, I examine artifact and volumetric data from features and fill to examine occupation duration and intensity and variation in site activities through time. Using these data, we can begin to reconstruct changes in settlement and community that may have taken place with the shift to a domestication economy.

20th Anniversary Southwest Symposium: Movement, Connectivity, and Landscape Change (Tempe, Arizona; January 2008)

Soil and Landscape Responses to American Indian Agriculture in the Southwest

Jonathan A. Sandor1 and Jeffrey Homburg2
1Iowa State University; 2Statistical Research, Inc.

Soil studies of prehistoric to contemporary American Indian agriculture across the Southwest indicate varied, dynamic responses to land use. Soil change is inferred from comparisons of agricultural fields to reference uncultivated areas (space-for-time substitution). Soil response pathways vary by initial ecosystem conditions, diverse agricultural methods, and environmental sensitivity to alteration (varying resistance and resilience). Terrain change detection is complicated by postfarming geoecological processes and land use. Soil change ranges from degradation (e.g., organic matter/nutrient decline, compaction, salt/sodium accumulation), to minimal net change, to enhanced soil quality. Ancient agricultural soils provide long-term perspectives on human-environmental relationships and land use sustainability.

Foraging Societies in an Arid Environment: Coping with Change in the American Southwest

Bradley J. Vierra

The American Southwest is an environmentally diverse region that ranges from upland mountains and high mesas to lowland river valleys and desert plains. It should therefore not be surprising that this variability would also be represented among past foraging societies that had to cope with this ever-changing landscape. Twenty years of hunter-gatherer research has only just begun to identify the nature of this diversity. This paper will focus on several principal research themes that are currently being studied by southwestern archaeologists: the Paleoindian-Archaic transition, Archaic foraging technology, early agricultural society, and forager-farmer relationships. Together these themes provide new insights into past foraging societies and possible avenues for future research.

American Cultural Resources Association SRI Foundation SRI Press Nexus Heritage General Services Administration (GSA)