Archeobotanical Remains from Trout Creek (CA-SLO-1644)

Archeobotanical Remains from Trout Creek (CA-SLO-1644) From Fitzgerald, R. T. 1997. Archaeological Data Recovery at the Trout Creek Site CA-SLO-1644 San Luis Obispo County California Prepared for the California Department of Water Resources California State Water Project, Costal Branch, Phase II. Charles H Miksicek, manuscript 2/16/1996 CA-SLO-1644 produced a small assemblage of stone tools and a large hearth feature that was radiocarbondated and yielded two dates ranging from ca. 2700 to 4200 BP. 4.3.6 Archaeobotanical Methods Nine flotation samples were analyzed from TEU 8. All of these samples were processed using a continuous-flow flotation device designed by this author which was modeled after the SMAP machine (Watson 1976). Each soil sample was first measured in a large graduated cylinder to determine the volume. The matrix was then poured into the float machine and gently stirred. Overflow from the machine containing carbonized seeds and wood charcoal was collected in nylon mesh with 0.25 mm openings. Sample processing continued until all charcoal was collected in the nylon netting which was then hung from a clothesline and dried. The remaining coarse sediments were then scanned for bone, lithics, and other artifactual material. After drying, each sample was first passed through a nested series of geological sieves with mesh sizes of 4.0, 2.0, and 0.5 mm. This pre-sorting removes many modern rootlets and produces subsamples with similar-sized particles which are more effectively scanned by the analyst. Each fraction was then sorted at 7X under a binocular dissecting microscope into its component parts. Uncharred seeds were counted and identified to evaluate the modern seed rain and to provide a measure for the degree of bioturbation and mixing within the soil column. To provide an additional monitor on the amount of faunalturbation in each sample, rodent fecal pellets and insect parts were quantified on a relative scale ranging from 0 (none) to 5 (abundant). All pieces of charcoal large enough to manipulate were identified from each sample. Each fragment was first fractured to give fresh transverse and radial sections and then identified at 30x under a binocular dissecting microscope. All seed and wood identifications were based on modern comparative material collected from south-central California and standard seed and wood keys such as Musil (1963), Martin and Barkley (1973), and Miles (1978). Taxonomic nomenclature follows Hickman (1993). 5.8 ARCHAEOBOTANICAL REMAINS All botanical materials identified in the Trout Creek samples are listed in Table 5-@ along with ethnographic uses from Mead (1972), Ebling (1986), and Strike (1994). Seasonality data come from Hickman (1993). Raw data are reported in Table 5-@2. This table includes sample volume before flotation, richness (the average number of charred seed taxa per liter), density (the average number of charred seeds per liter), the total weight of all charcoal fragments larger than 0.5 mm, the bug part index, the rat pellet index, uncharred seeds, carbonized plant remains, and wood charcoal. Some evidence for disturbance is present in all levels of the TEU 8 column in the form of insect parts, recent rodent fecal pellets, or uncharred seeds (Table 5-@2). It is most likely that all of the uncarbonized remains are recent intrusives and are not associated with the prehistoric use of the site. Several of these intrusive taxa are Eurasian weeds introduced to California during the Mission Period (filaree, catchfly, wild oats, bromegrass, foxtail barley). Both charcoal concentrations and seed densities are rather high. The charcoal fragments and carbonized seeds seem very well preserved (sharp breaks, minimal mechanical abrasion) and clean (older materials are often impregnated with soil particles). Both the preservation status and density of charred remains suggests that the macrofossils from this particular column do not seem very old (Late Period or more recent). Although older, temporally diagnostic artifacts are present at the Trout Creek site, the plant macrofossils from TEU 8 do not seem to be associated with the oldest occupation. They do appear cultural however and not residue from natural fires mixed into the soil column by bioturbation. Charred plant materials left behind after natural fires often represent a diverse mixture of species and plant parts (stems, floral parts, fruits, seeds, leaves). The materials that are preserved are mostly nut fragments and charcoal, from a limited range of species, all of which have documented uses in the local ethnobotanical literature. Charred fragments of acorn kernel are the most ubiquitous non-woody plant remains, present in all nine samples. Pieces of acorn shell are only present in the uppermost sample. "Unknown vesicular material" is also very common. This, rather generic, analytical taxon describes fragments of non-woody plant material that lacks any diagnostic micro-anatomical structure. It may include fragments of nutmeats that lack distinctive vascular bundles or pieces of processed foodstuffs such as seedcakes or gruel. Pieces of buckeye kernel are the third most abundant potential food item. This is unusual since buckeye is often considered a famine food that was only used when other more preferred foods were in short supply (Mead 1972, Ebeling 1986, Strike 1994). These nuts are very toxic and require more careful leaching than acorns. In addition, Trout Creek is near the southernmost limit of the modern range for buckeye trees near the coast (Griffin and Critchfield 1976:Map 9). Eastern populations of California buckeye extend south to the Antelope Valley in Los Angeles County. The presence of buckeye macrofossils in the Trout Creek assemblage may indicate a more extensive range for this species in the past, and that the remains come from a time with a slightly different climatic regime. In addition to acorn nutmeats and buckeye kernels, gray pine nutshell and fragments of monocot rhizome are also present in several float samples. The mixture of acorns, pinenuts, and buckeye (all storable fall resources) and starchy rhizome fragments (generally gathered in early spring) suggests that these plant remains represent a fall through early spring occupation. The people who used this site were probably elsewhere during other parts of the year, possibly near the coast collecting marine resources. One of the most dramatic features of the Trout Creek archaeobotanical assemblage is the very high proportion of acorn kernels to nutshell fragments. Most archaeological sites with abundant acorn macrofossils have mostly shell fragments. Table 5-@3 summarizes acorn data from fifteen other sites in California. Although Table 5-@3 reflects a wide range in the acorn kernel to shell ratio, the average is around one kernel fragment to 26 nutshell pieces. The nearby Salinas River Crossing site is the only locality, besides Trout Creek, with a high kernel to shell ratio. These results suggest a very different acorn processing technique was used by the occupants of the Trout Creek site. In most parts of California dry acorns were first shelled and the nutmeats were then ground in some type of mortar (Mead 1972, Ebeling 1986, Strike 1994). The waste shells, an excellent supplemental fuel, were often tossed into cooking fires where some were preserved by incomplete charring. Ground acorn meal was then leached several times with water and then cooked into soup, gruel, or bread. An alternative method of leaching acorns was to bury them in sandy riverbeds for long periods of time (up to a year). The kernels were then consumed without further processing or roasted in pit ovens. Long-term, streambed leaching was most commonly used by northern California groups like the Shasta and Karok. The same method was often used for buckeye nuts. A few species of acorns have low enough tannin content that they may be consumed after roasting without any leaching (northern California's deer oak [Quercus sadleriana], Arizona's Emory oak [Q. emoryi], and the eastern basket oak [Q. michauxii]). The high proportion of charred kernels at Trout Creek may indicate that whole nuts themselves were roasted probably in pit ovens. Gray pine is the dominant charcoal taxon from the site (81 percent, Table 5@-2). Live oak, the most abundant tree species in the area today, only represents 14 percent of the identified charcoal assemblage. Valley oak, which now grows immediately over the sampled unit, is only present in the soil column between 10 and 30 cm. A single piece of wild grape is the only riparian taxon represented despite the proximity of the site to Trout Creek. The paucity of valley oak, near absence of riparian taxa, the abundance of pine, and the low proportion of live oak suggests that these remains are left behind from a time with a drier and possibly warmer climate. References Cited Ebeling, Walter 1986 Handbook of Indian Foods and Fibers of Arid America. University of California Press, Berkeley. Griffin, James R. and William B. Critchfield 1976 The Distribution of Forest Trees in California. Pacific Southwest Forest and Range Experiment Station, Berkeley. Hammett, Julia E. 1990 Analysis of Plant Remains from the 1987 Excavations at Talepop (CA-LAN-229). In: Archaeological Studies at Site CA-LAN-229, Malibu Creek State Park: An Experiment in Inference Justification, edited by L. Mark Raab, Appendix 2. Northridge Center for Public Archaeology, California State University at Northridge. Hickman, James C. (general editor) 1993 The Jepson Manual: Higher Plants of California. University of California Press, Berkeley. Martin, Alexander C. and William D. Barkley 1973 Seed Identification Manual. University of California Press, Berkeley. Mead, George R. 1972 The Ethnobotany of the California Indians. Museum of Anthropology, University of Northern Colorado, Occasional Publications in Anthropology, Ethnology Series No. 30, Greeley, Colorado. Miksicek, Charles H. 1995a Archaeobotanical Remains from CA-MNT-1601. Technical report submitted to Archaeological Consulting Services, Salinas, CA. Miksicek, Charles H. 1995b Plant Remains from Pfeiffer Beach (CA-MNT-798). Technical report submitted to Cabrillo Community College, Santa Cruz, CA. Miksicek, Charles H. 1995c Archaeobotanical Remains from CA-MEN-2306 and CA-MEN-2307. Technical report submitted to San Jose State University, San Jose, CA. Miksicek, Charles H. 1995d On The Cusp of History: Archaeobotanical Remains from CA-YOL-182. Technical report submitted to UC Davis, Davis, CA. Miksicek, Charles H. 1995e Charred Plant Remains from CA-MNT-361. Technical report submitted to BioSystems Analysis, Inc., Sacramento, CA. Miksicek, Charles H. 1993 Archaeobotanical Remains from CA-SCL-732/H. Technical report submitted to Archaeological/Historical Consultants, Oakland, CA. Miksicek, Charles H. 1992 Archaeobotanical Remains. In Archaeological Data Potential Assessment at CAMNT-515, CA-MNT-540, CA-MNT-567, and CA-MNT-862, Ft. Hunter Liggett Military Installation, California. edited by Brian Wickstrom and Thomas L. Jackson, pp. 3.12-3.19, 3.29, 3.33-3.34, 3.46-3.50, 3.52-3.55, BioSystems Analysis, Inc. Submitted to U. S. Army Corps of Engineers, Sacramento District, Contract No. DACA05-90-C-0175. Copies available from U. S. Army Corps of Engineers, Sacramento. Miles, Anne 1978 Photomicrographs of World Woods. Her Majesty's Stationery Office, London. Musil, Albina F. 1963 Identification of Crop and Weed Seeds. U. S. Department of Agriculture Handbook No. 219. Washington, D. C. Strike, Sandra S. 1994 Ethnobotany of the California Indians, Volume 2. Aboriginal Uses of California's Indigenous Plants. Koeltz Scientific Books USA, Champaign, IL. Watson, Patty Jo 1976 In pursuit of prehistoric subsistence: A comparative account of some contemporary techniques. Midcontinental Journal of Archaeology 1(1): 77-100. Table 5-@. Plant Remains Identified by Flotation from Trout Creek (CA-SLO-1644). Common Name Scientific Name Part Bromegrass ** Catchfly ** Filaree ** Foxtail Barley * Miner's Lettuce Tarweed Wild Oats * Monocot Rhizome Vesicular Material Buckeye Gray Pine Live Oak Valley Oak Buckthorn Family Wild Grape Bromus sp. Silene sp. Erodium spp. Hordeum leporinum Claytonia perfoliata Madia or Hemizonia Avena fatua Monocotyledoneae unknown Aesculus californica Pinus sabiniana Quercus agrifolia Quercus lobata Ceanothus or Rhamnus Vitus californica u u u u u u u m m s s,m,w s,w s,w w w Use Season Indicated spring R spring N,U,W N,U,W N,U,W N,U,W F?,M,W F,U,W fall fall fall fall year round year round Key: * - introduced species, ** - some species native, u - uncarbonized seed (etc.) s - carbonized seed, m - miscellaneous parts, w - wood charcoal, F - edible fruit, M - medicinal, N - edible nut, U - utilitarian (fiber, basketry, etc.), W - wood, R - edible root Table 5-@2. Charred Plant Remains from Trout Creek (CA-SLO-1644, TEU 8). Sample Depth (cm) 0-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80 80-90 Site Sample Volume (Liters) Charred Taxa/Liter Charred Seeds/Liter Rat Pellet Index Bug Part Index 4.0 0.75 1.25 1 1 4.0 1.00 4.25 0 1 4.0 1.00 7.00 0 1 4.0 0.75 6.25 0 0 4.0 0.75 6.25 0 1 4.0 0.75 4.50 0 0 4.0 1.00 8.00 0 1 4.0 1.00 5.75 0 1 4.0 1.25 4.75 0 0 1 5 3 6 1 1 5 3 1 1 6 9 0.92 5.33 Uncarbonized (Intrusive) Seeds: Acorns Filaree ** Catchfly ** Tarweed Miner's Lettuce Wild Oats * Bromegrass ** Foxtail Barley * 53 4 53 8 1 12 6 2 3 6 2 3 1 1 3 9 1 4 12 10 2 4 11 11 9 9 9 8 3 7 1 15 15 1 1 3.0 1.5 1.9 1.7 0.7 26 2 23 5 17 25 7 2 1 Charred Seeds: Ubiquity Acorn Shell Acorn Kernel Vesicular Material Monocot Rhizome Buckeye Kernel Gray Pine Nutshell 2 1 1 1 Wood Charcoal (gms): 0.4 Buckthorn Family Gray Pine Valley Oak Live Oak Wild Grape Vine 1 10 7 1 4 8 2 3 2 11.1 100 100 55.6 88.9 22.2 0.7 0.7 0.7 % 20 18 13 14 5 4 6 5 0.2 0.3 0.2 Miscellaneous Remains: Chert Flakes (gms) Basalt Flakes (gms) Small Animal Bone (gms) Charred Termite Pellets Charred Conifer Bark 0.4 0.4 2 3 2 2 1 Key: * - introduced species, ** - some species native 0.2 0.5 81.4 3.4 14.2 0.5 Table 5-@3. Acorn Kernel to Shell Ratios from Various California Sites. Site Number of Samples Acorn Kernel: Ubiquity Shell Ratio CA-MNT-1601 CA-MNT-798 CA-MEN-2306 CA-YOL-182 CA-SCL-690 CA-LAN-229 CA-MNT-515 CA-MNT-567 CA-MEN-2307 CA-SCL-732 CA-MNT-862 CA-MNT-521 CA-MNT-361 CA-MNT-569 Salinas River CA-SLO-1644 4 6 5 15 26 8 8 14 5 9 6 12 5 10 27 9 100 50 80 100 50 100 86 62 100 78 67 42 100 80 78 100 0 : 35 0 : 15 1 : 108 1 : 91 1 : 31 1 : 23 1 : 21 1 : 12 1 : 12 1 : 10 1:2 1:2 1:2 1:1 6:1 35 : 1 Age Historic Late Late Protohistoric Middle Reference Miksicek 1995 Miksicek 1995 Miksicek 1995 Miksicek 1995 Miksicek r.i.p. Hammett 1990 Late Miksicek 1992 Late Miksicek 1992 Historic Miksicek 1995 Middle Miksicek Recent Fire Miksicek 1992 Middle Miksicek r.i.p. Historic Miksicek 1995 Late Miksicek r.i.p. Miksicek r.i.p. this report r.i.p. - research in progress