Defining the Upper Clay Floor

As noted in an earlier post, one of our greatest surprises this field season at Burrell Orchard was the discovery of a second clay floor. But unlike the first floor, this one was found just 15 to 20 cm (about 6 to 8 inches) below the surface! On most sites I have worked in northern Ohio, such a shallow feature would have been badly damaged, if not destroyed, by a century or more of plowing. But such was not the case at this amazing site. It seems that the area in which we are working is just a few meters beyond the most actively cultivated portion of the original farm. Of course, millennia of root growth, erosion, and rodent digging have taken their toll on this extremely rare piece of Ohio ancient history, but still this floor is amazingly well preserved after 4000 years (Figure 1).

Figure 1. Exposed southwest section of the upper clay floor. The excavation block shown here is three meters wide; the irregular gray stains on the floor are excavated pit features.

Based on our growing knowledge, this upper floor appears to be roughly oval in plan and measures at least four meters long (N-S) and three meters wide. The uncertainty is due to the fact that we have yet to expose the northern and eastern margins of the floor. Areas of orange-red clay, marking the locations of ancient fires, appear here and there across this clay surface. These burned patches may represent hearth features used by the occupants, who also dug small pits into the floor. Most of these pits contain very little in the way of artifacts, but some include bits of deer or other animal bone. Many may be small cache or storage pits. As these small pits were excavated, we noticed that the upper clay floor capped additional floor layers separated by thin lenses of midden soil (Figure 2). I noticed at least three of these subfloors in several excavated areas, and up to four floors were visible as small sections of yellow clay protruding here and there along the western margin of the upper floor.

Figure 2. Cross-section of small pit in the floor of the upper clay floor; note charcoal concentration in profile wall and yellow clay subfloor showing at the bottom left of the excavation.

Based on our experience with the deeper clay floor of Structure 1, we were careful to look for post molds lining the edges of the upper floor. After some careful troweling, we found several post molds forming an arc around the southwestern edge of the upper floor which may represent a wooden post structure built on top of the clay surface. A few days later, as we removed some of the surrounding midden soil, we exposed four or five post molds in a similar configuration along the edge of a deeper subfloor. This evidence may indicate that multiple structures were built and rebuilt, one on top of the other over decades or perhaps centuries at Burrell Orchard.

This discovery that several rebuilding episodes took place in this area of the site was expanded as we removed additional small sections of the upper floor to expose subfloor features, such as fired clay surfaces (hearths?) and FCR clusters. Small pits like the kind we recorded on the upper floor appear to have been constructed on these earlier structural floors. The most interesting of these was Feature 15-19, the small pit in which the fragment of slate bannerstone was deposited and later covered over by the subsequent, and final, clay floor. Thus, it seems likely that each layer of clay floor contains its own set of features which represent the activities of several generations of Native American families living at this site.

Exploring Structure 1

Last Friday we completed another successful field school program at the Burrell Orchard site. We made several significant discoveries during this last week, and I will discuss them in this and subsequent posts. Heading into this season, my primary goal was to excavate the remaining sections of the deep clay floor feature we discovered in 2014 and determine if it indeed represented the floor of a structure. I think we achieved this goal with the exposure of more clay floor in Unit 496N 512E, as well as some other interesting features.

Once this unit finally dried out sufficiently for us to continue excavation, we identified a distinct line of post molds extending north-south along the western margin of the clay floor (Figure 1). This series of small posts appears to line up precisely with the end of the post configuration identified last season in Unit 498N 512E. Contrary to our expectations, however, this line does not curve sharply to the east but extends farther south into unexcavated territory. A few days after this post line was recorded, a parallel row of posts was uncovered about 2.0 meters to the east (Figure 2). This line also connected with an arcing configuration just to the north in Unit 498N 514E that was recorded the week before. Together, these post molds form a U-shaped configuration, with the closed end of the “U” to the north. It seems probable that this pattern, which I have dubbed “Structure 1” extends southward to form an oval dwelling measuring at least 4.0 meters long (north-south). Unfortunately, time ran out before we could excavate the next unit to the south.

Figure 1. Clay floor (yellow soil) and interior features in Structure 1; post molds are marked in white.

Figure 2. Projected outline of Structure 1 based on locations of post molds (shown in white); north is toward the top of the image.

One truly unique aspect of this likely house floor is what appears to be a prepared clay basin (Fea. 15-17) located in the southeast corner of Unit 496N 512E (Figures 1 and 3). This shallow dish was molded out of the same clay used to construct the structure floor and a rounded rim was added, most likely to contain whatever material was placed within this receptacle. Lying on the surface of this basin was a bone awl or perforating tool and the astragulus (ankle bone) of a deer (Figures 3). The purpose of this construction remains a mystery. It was not used as a fire pit, since the clay was not altered to the distinctive red-orange color seen on many areas of the clay floors where fires were made. I don’t think this basin would have served very well as a surface for grinding, since the clay would not have held up to much scraping with a groundstone tool. Perhaps the basin held plant material or served as the base for basket containers. Maybe it was a water dish for the family dog! We really don’t have a clue, since, to my knowledge, nothing like it has been found before in Ohio.

Figure 3. Excavation of the clay basin (Feature 15-17); bone awl is indicated by arrow

One final surprise awaited us when we excavated Feature 15-22, a round pit situated near the center of the floor (Figure 1). The fill of this pit was very dark and organic. Among the remains were a large quantity of butchered deer bone and another deer bone awl (Figure 4). But most surprising was the discovery of four very large stones arranged in a cluster on the bottom of the pit, along with several smaller stones stacked above and around the larger ones (Figure 5). Many of these rocks showed signs of use as grinding stones, which suggests that Feature 15-22 was a cache pit used to store some of the less portable household tools below the floor. The fact that all the large stones were placed flat-side up with their surfaces at about the same level indicates that this cluster may also have served as a hard base or platform to support something used within the house. But again, exactly what this may have been remains uncertain.

Figure 4. Deer bone awl found in Feature 15-22.

Figure 5. Feature 15-22 and contents.

The discovery of Structure 1 with its clay floor is amazing to me. To be able to stand on a Late Archaic house floor, touch a clay basin made by the inhabitants, and peer into a storage pit that was last opened some 4000 years ago has been one of the highlights of my archaeological career.

Bannerstone Discovery

This week at Burrell Orchard proved very productive, despite the almost daily rain showers that flooded some of our most promising excavation units (Figure 1). Nevertheless, our valiant crew slogged through the swamp, screened for artifacts in the rain, and kneeled in mud to make good, steady progress.

Figure 1. Rain-soaked floor of Unit 496N 512E.

Spirits were greatly heightened by the unexpected discovery of a rather rare artifact known as a bannerstone. “Bannerstone” is the name given to a class of expertly carved and ground slate artifacts that many archaeologists consider to have been weights on the “atlatl” spear-thrower. Despite this rather mundane function, many bannerstone were so carefully made and artistic in form that it seems that they would have also carried some degree of ritual or symbolic significance. In any case, yours truly turned one up while examining some dark soil stains on one of the unit floors. Interestingly, the bannerstone was partially buried beneath a section of clay floor, as if it had been deliberately sealed into the small pit subsequently found below.

Our specimen is broken, perhaps intentionally, and represents about one half of its original form (Figure 2). This variety is known as a “winged” or “butterfly” bannerstone for the wide flanges extending outward from the central bore hole. It is thought that the bannerstone was inserted over a cylindrical portion of the spear-thrower. Our specimen does not appear to have been finished, since many scratches from smoothing the stone are still apparent. Also, the artifact is neatly broken at the central bore hole, which suggests that this destruction was the result of poor drilling technique. It is also possible that the bannerstone was intentionally broken or “killed” by its owner, possibly as a sacrifice or an effort to release the spirit of this fine object. The fact that it was carefully buried under a clay floor in a small pit points to the making of an offering, perhaps during the renewing of the house floor with another clay layer. We will never know for sure, but the discovery of such a rare object in an otherwise artifact-sparse section of the site leads me to think that its placement here was intentional and had great significance.

Figure 2. Two views of slate bannerstone fragment found in Unit 496N 516E (arrow points to central hole).