Archaeological Fieldwork: June - August 2011

Post (Garza County), Texas

The ca. 83,000 acre ranch, near Post, Texas is part of a vast turn of the century ranchland that has remained within the same family, having been used continuously for cattle ranching since the 1880s. The landscape generally is pristine and sites undisturbed due to the highly limited access to and minimal development of the ranchland. This situation has resulted in a unprecedented preserved surface expression of the cultural landscape. The research value indicated at targeted sites suggests that they hold significant potential to inform regional models of aboriginal behavior and decision-making during thousands of years of occupation. Understanding the relationship of the material remains recovered from these sites within a wider landscape perspective represents one of the primary research objectives of the ongoing program of investigations

Current research began in 2005 and the fieldwork for the 2011 season takes place in several localities. Lab work is carried out in the on site camp facilities to help facilitate continuing research landscape development and hunter-gatherer land use patterns.

Physiographic Setting
Garza County is located in western Texas with part of the county on the eastern Llano Estacado and the other part below the caprock on the Rolling Plains. The landscape below the caprock consists of rough broken land that is drained by numerous tributaries of the Brazos River system. The South Fork of the Double Mountain Fork of the Brazos River runs through the property trending from the northwest to the southeast. The targeted sites are located just above and below the escarpment.

Previous Investigation
Fieldwork has identified and sampled a number of buried soils in various topographic settings across the ranch, investigated outcrops and gravel bars as stone tool resources, surveyed and mapped numerous sites, and excavated hearths. Among the sites, Cowhead Mesa is a remnant of the Southern High Plains situated just off the edge of the eastern escarpment. Prehistoric hunter-gatherer groups and Historic Southern Plains tribes were attracted to the mesa evident by the rock art panels that adorn the sandstone cliffs edges, and over 2,300 artifacts left on the mesa top. Art elements depicted on the panel included possible church missions on fire, human figures in combat, a possible shaman, a three-toed box turtle, and a bovid. These rock art panels have been recorded in detail with the use of a Leica 3D laser scanner to shed more light on the artistic style of rock art on the Southern Plains.

On top of Cowhead Mesa, the latest in GPS technology was used to record the distribution of surface artifacts. Several lithic clusters were identified that represent the manufacture of stone tools. Two hearths were excavated to document the camping activities of these hunter-gatherer groups.

A very large thermal feature at PLK-34. This feature was a very well constructed large basin that was rimmed with large caliche hearthstones. The central interior of the feature also was choked with these large hearthstones. The basin contained very dark organic hearth fill and charcoal that dated to the Late Archaic period. Such features apparently were constructed to process plants.

The most recent fieldwork focused on survey and mapping of a number of prehistoric hunter-gatherer campsites and historic Anglo sites located in different landscapes across the Southern High Plains and Rolling Plains ecological border. As a part of this effort, hearth features were excavated, documented, and sampled for radiocarbon dating and phytolith analysis.

Several profiles containing buried soils were recorded to ascertain periods of landscape stability and to understand how environmental changes impact the landscape and vegetation. Samples were taken from the buried soils for radiocarbon dates, carbon isotopes, and phytoliths to determine when the soils formed, identify the plant communities, and explore what the environment was like in the past. Environmental changes have big impacts on the distribution of resources, and, therefore, have an effect on how prehistoric hunter-gatherer groups and historic peoples used the landscape.

2011 Fieldwork
Fieldwork for the 2011 field season focuses on continued survey and detailed mapping of hunter-gatherer sites along the edge of the Southern High Plains escarpment. A combination of a GIS Trimble base station and total station are used to map the distribution of materials at several key hunter-gatherer sites. Additionally, hearth features, bone beds, and buried soils continue to be targeted for recording, sampling, excavation as appropriate, and profiling. There will also be test excavations at an early Euro-American dugout site that was constructed along the edge of the escarpment. Preliminary work has uncovered evidence that this was one of the first homestead sites in the region.

Methodology

Field. Primary components of the fieldwork consist of:

- Systematic recording of the archaeological materials to examine spatial, temporal, and cultural relationships;
- Pedestrian survey of the areas to be investigated
- Hand excavation of 1m X 1m units in 10cm levels and 2.5cm sublevels
- Recording, mapping, and photographing of material found in situ
- Recovery of micromaterials from provenienced sediments by water washing through nested fine-mesh screen.
- Use of standardized Museum forms to record all information

Laboratory. The on-site lab involves all crew members checking in objects, crosschecking of field forms, collections organization, and sorting of all resultant concentrates from the water washing of excavated sediments. All recovered objects and documentation are transported to the Landmark's Quaternary Research Center (QRC) for additional processing and analysis. Processing entails accessioning, cleaning, identification, stabilization as necessary, cataloging, bar-coding, data inputting, inventory, and packaging.