Saturday, June 13, 2009

Field School Begins at Heckleman site

This past Friday, we completed our first week of field school excavations at the Heckleman site. On Monday we began a shovel-test survey of the eastern end of the site within the large enclosure. This type of survey involves the excavation of 50 cm by 50 cm squares along east-west transects. The goal is to sample the contents of the plow zone in order to identify the spatial distribution of artifacts such as pottery, flint debitage, animal bone, fire-cracked rock, and more recent historic material. By end of the day on Tuesday our crew had excavated 16 shovel-tests and recovered good samples of artifacts. The counts of artifacts derived from this survey will be used to construct maps of artifact densities across the site. We are looking for patterns in these distributions which may help identify what activities were carried out by the prehistoric inhabitants and where these took place. In the image below, you can see small groups of students working on shovel-tests along the 490N line.


Below is a close-up view of a shovel-test in progress.



Our testing paid some immediate benefits when we uncovered several possible pit features and post molds. The small shovel-test units at these locations were expanded into larger units to exposed the suspected features and permit their excavation. I will discuss some of these discoveries in subsequent posts. In one excavation we uncovered the base of a Middle Woodland (Lowe cluster) projectile point at the base of the plow zone and just above a feature. The point can be seen in the lower right corner of the profile wall shown below.


Friday, February 13, 2009

Summer Field School at the Heckleman Site

In the summer of 2009, we will carry out test excavations at the Heckleman site, a prehistoric Native American settlement located on the Huron River near Milan, Ohio. The Heckleman site (33Er14) was first investigated in 1968 by Dr. Orrin Shane of Kent State University. These and subsequent excavations discovered a large prehistoric ditch feature that enclosed a large settlement thought to date to the Early Woodland period (ca. 500 to 100 BC). Shane's crews also found numerous Middle Woodland period (ca. 100 BC to AD 400) stone tools and pottery sherds resembling Ohio Hopewell culture artifacts from southern Ohio.

In 2008, we commissioned a series of geophysical surveys by Dr. Jarrod Burks of Ohio Valley Archaeology, Inc. Jarrod conducted an extensive magnetic survey of the site area using a gradiometer. This device is able to pick up magnetic 'anomalies' in the subsoil, some of which can be prehistoric features. We were delighted when his resulting maps revealed not one but two parallel ditch features extended north to south across the promontory.

Dr. Jarrod Burks conducts the magnetic survey, Brian Scanlan assists in the background.

The magnet survey also identified an oval enclosure to the east of the ditch features which may represent a Late Prehistoric period (ca. A.D. 1200-1600) village site. Additional surveys, which measured subsurface electrical resistivity and magnetic susceptibility (too technical to explain here), were carried out over more limited areas of the site. The resistance readings revealed additional possible prehistoric features and some areas of recent disturbance which may be the traces of Shane's earlier excavations. The magnetic susceptibility survey identified a large area of midden soils which covers most of the area to the east of the parallel ditch features. This tells us that most of the prehistoric activities took place within this large enclosed area.

In the fall of 2008, 'ground-truthing' of the innermost ditch anomaly was conducted by archaeologists from the Firelands Archaeological Research Center in Amherst, Ohio. Excavations revealed a substantial prehistoric ditch that measured nearly two meters wide and a meter deep.

Vertical section of the ditch feature showing light and dark fill layers.


Crew members Michael Niece (left) and Glen Boatman remove samples of the ditch fill for flotation processing.

The team recovered Hopewellian bladelets and projectile points made of Flint Ridge chert as well as Middle Woodland (Esch phase) pottery, butchered animal bones, and charred plant remains. It now appears that the Heckleman site was the location of three large prehistoric occupations which spanned a period of as much as 2000 years.

Expanded-stem Middle Woodland point made of Flint Ridge chert from ditch fill (image by Brian Mickey).

In the summer of 2009, CMNH archaeologists will return to the Heckleman site to systematically test selected areas to identify the various prehistoric occupations and to continue to ground-truth many of the subsurface anomalies and oval enclosure located by the geophysical surveys. For additional information about this summer's project see the Museum's website.

New Botanical Data from Burrell Orchard

Back in November, I sent eight samples of carbonized plant remains from the summer 2008 excavation out for analysis. These samples were derived from the light fraction residue of flotation processing. Two samples came from the lower (dark) midden stratum (see image below), one from a smudge pit, and five from pit features. The botanical remains were analyzed by Dr. Leslie Bush, an ethnopaleobotanist in Manchaca, Texas.


The results are not very spectacular but informative. As expected, a large proportion of the plant remains (14 g) were fragments of wood charcoal, primarily from white oak, red oak, ash, and hickory. Interestingly, carbonized nutshell was even more common (19 g) than charcoal. The vast majority was hickory, followed by black walnut, and one fragment of acorn. The result was a nutshell to wood (charcoal) ratio of 1.36 which indicates a strong preference for nut resources by the site inhabitants. Early survey records from the French Creek area of Lorain County report that the ridgtops supported forests dominated by oaks and hickories. Thus, it looks like the Late Archaic residents were maximizing their use of these local plant resources.

One surprise was the identification of four carbonized bulb fragments from the wild hyacinth, also known as Atlantic camus (Camassia scilloides). This native plant produces an edible bulb that was harvested by Native Americans in historic times and roasted in earth ovens. All four bulb fragments from Burrell Orchard were found in Feature 08-26, a medium-sized cooking pit in unit 500N 514E. Since this plant most commonly grows on the same kinds of moist, wooded slopes bordering streams like French Creek, the site inhabitants probably did not have to go far to collect these bulbs.

The relatively large quantity of hickory nutshell at the Burrell Orchard site most likely points to a fall occupation when these nuts would have been most abundant. In additon, the best time to collect camus bulbs would have been the late fall to winter months when these parts of the plant would have reached their maximum size. When we add this information to the prevalence of deer bones and antler (another fall-harvested food source), it becomes very likely that the Late Archaic residents of Burrell Orchard were present during at least some of the colder months of the year, perhaps from October to December.