What is Happening Now at the Headwaters Site

For the past several months the investigation team has been organizing, processing, and interpreting the data gathered during the Big Dig. The Headwaters site is rich in information, and quite a bit of time has been spent by the team in these tasks. A quick summary is below:

• We have 45 radiocarbon dates from various deposits at the site, which help to group the cultural deposits into specific slices of time.
  • What have we learned? The site has been occupied for more than 8,000 years, but the most intensive occupations found so far were during the Late Archaic Period . For example:
    • A group of small burned rock hearths (<1 meter in diameter) stacked one atop another in Block C were very close in age. They all fell within 2,130-2,460 years BP.
    • Three large (1.5-2 meters in diameter) burned rock ovens and the associated midden field in Block A were dated to 2,510-3,300 years BP.
    • The huge midden uncovered in Block D dated to 830-2,220 years BP, with the youngest date on the top and the oldest at the bottom.
  • The youngest pre-contact feature found at Headwaters is Feature 34, at 817 years BP (Late Prehistoric)
  • The oldest feature found, Feature 64, dates to 6,970 years BP. (Early Archaic).
• The material from 74 features was collected and organized. Different feature types were identified and analysis was conducted on the burned rock and artifact data associated with those features.
  • What have we learned? Archaeologists working in Central Texas often encounter collections of fist-sized burned rocks, and the overwhelming majority of features found at Headwaters consist of such fire-cracked rocks. These were identified as components of aboriginal cooking technology. They are the remnants of numerous burned rock ovens used to cook carbohydrate-rich foods; such as sotol, bulbs, or acorns; to be eaten immediately, saved for long term storage, or packed as traveling food. Once the cooking was done, the burned rock was discarded in a nearby midden field. Interestingly, two major types of ovens were found at Headwaters: small (<1 meter/3 feet in diameter) and large (1.5-2 meters/5-6 feet in diameter).
    • In Block A, the team found three large burned rock ovens surrounded by a midden field of trash. The size of the ovens indicates that more than one-meal’s worth of food was cooked in each one. These features match the typical burned rock oven type found in Central Texas.
    • In Block C, the excavation team uncovered several small burned rock ovens, stacked one on top of the other. These ovens may have served a different purpose than the large ovens, as the amount of sotol or acorns that could be cooked is such a size would be almost two-thirds less than the large oven. Reasons why this is the case are still being explored.
• The stone tool analysis was completed with over 550 individual artifacts analyzed. This includes formal stone dart and arrow points, bifaces, unifacial tools such as gravers and scrapers, cores, modified flakes, and groundstone.
  • What have we learned? When the  team started these excavations, we hypothesized people who lived here would have wanted to stay for a long time (and who wouldn’t?!?). A stable, clean water supply, lots of local food resources, and plenty of material for shelter building. It was surprising to see the lithic analysis lead in another direction. Most of the tools and tool remnants analyzed are associated with high mobility; people who were accustomed to moving around and spending a lot of time traveling between different landscapes. We now are looking into why this seems to be the case at the Headwaters site when the conditions would seem to favor people staying longer.
• Twenty-four samples were submitted for macrobotanical analysis. This involves identifying the species (where possible) of plants that created the small filaments of fibers and charcoal in the soil around archaeological features.
  • What have we learned? Several tree species were identified from charcoal samples obtained, including: Plateau live oak (Quercus fusif), oak (Quercus spp.), Bluewood Condalia (Condalia hookeri), Texas persimmson (Diospyros texana), Huisache (Vachellia farnesiana), Hogplum (Spondias mombin), Juniper (Juniperus spp.), Legume (Fabaceae spp.), and the Hackberry/elm family (Ulmaceae spp.). Additional species were identified in macrobotanical remains, such as nutshells from the Walnut family  (Juglandaceae) and bulb fragments such as camas (Camassia spp.), false garlic (Nothoscordum bivalve), wild onion (Allium spp.). Seeds from goosefoot (Chenopodium spp.), the sedge family (Carex spp.), and Lace hedgehog cactus (Echinoceresus reichenbachii) were also found.