New Field Season at Burrell Orchard Underway

On May 17, preliminary test excavations began at the Burrell Orchard site with volunteers from the Firelands Archaeological Research Center (FARC). A 1x1m excavation unit was laid out in the area surveyed with Ground Penetrating Radar (GPR) in October last year. At this spot, the GPR detected a particularly strong reflection beneath the surface that is similar in form to the signal made by the clay floor feature we identified last summer (see Blogging Archaeology post for 7-12-2014). So, in this new spot, we hope to find evidence of a second structural floor dating to the Late Archaic period, about 4000 years ago.



Figure 1. Excavating the first test unit of the season.

Excavation through the plow zone deposits quickly turned up flint flakes and fire-cracked rock (FCR). Going deeper, small amounts of burned (calcined) animal bone and a few fragments of flint projectile points were recovered. Although fragmentary, these artifacts were easily identified as the long, narrow, stemmed lanceolate knives and spear tips that were used by the Late Archaic peoples who lived here.

At the 40 cm deep level, several patches of burned soil were detected, one of which was covered with a small amount of FCR. These features appear to represent locations where surface fires were made or are the very bottoms of small roasting pits. Elsewhere on the unit floor, careful troweling exposed small concentrations of charcoal. During the past two field seasons (2008 and 2014) we have identified similar features at approximately this level, some of the features were accompanied by flat-lying concentrations of siltstone fragments. These stone “pavements” may represent flat work areas or possibly the paved bottoms of cooking facilities. In any case, these clusters of thermal features, FCR, and burned bone likely represent living floors on which daily food processing and preparation activities took place. Interestingly, past experience at this site tells us that such floors are stratified into at least two levels at Burrell Orchard, and, thus reflect repeat visits to this site over a period of centuries. On our next visit, we will section the features and continue excavation of the midden soil to see if any clay surfaces appear.

Figure 2. The floor of the test unit showing two of the burned soil features (raised areas) at left. (If you look closely, you can just see the orange tint to the soil at these spots.)

House Wall and Clay Floor

On Thursday we discovered evidence that the curious clay layer may have served as floors for dwellings.  A careful examination of the clay floor exposed in unit 498N 512E revealed an arc of post molds running along the edge of the floor.  These posts measure about 5 to 7 cm (1.5 to 2.5 inches) in diameter and penetrate through the floor.  The white dots in the image below mark these post molds.  The red areas are heat-oxidized areas of the floor; most likely places where fires were made.  The dark soil area on the left (west) represent where shallow pit features were dug, parts of which cut out small sections of the floor.  We are not sure what these pits were used for, but they contain significant amounts of animal bone and some fire-cracked rock.

One final feature of note was found in the southeast corner of the excavation unit (lower right).  This small, dark, shallow pit cut through a burned area of the floor, which tells us that it definitely post-dates the creation--and maybe occupation--of the dwelling that was built here four millennium ago.

Finding the Clay Surface

This past Thursday, we found the base of the midden in unit 500N 512E at about 55 cm bd.  In the process, we uncovered the unusual yellow clay layer first discovered in 2008.  At that time we thought this clay was the natural subsoil that underlies the midden across the site.  Instead, it turned out to be a cultural surface resulting from the human occupation of the site.  We know this because beneath the yellow clay is an organic soil stratum which contains prehistoric cultural material.  We are not yet sure how this clay layer was created.  It may be the backdirt from digging deep pits dug nearby that penetrated the natural sandy clay subsoil.  But it may instead represent a deliberately created floor or working surface.  If so, then its presence shows that the Late Archaic inhabitants of this site took time to modify their settlement in a way that would last some time.  The image below shows the clay stratum and a large pit feature that appears to cut through this layer.

Next door, in unit 498N 512E, the dark organic midden soil was still being encountered.  Deer bone and antler, and carbonized nutshells are being found in abundance.  Among the finds was the base of a large flint drill.  On Friday, a drill tip was found near where the base turned up.  Not surprisingly, the two fragments fit together to form a long tool that measures about 12 cm (4.5 in) in length as shown below.  This exceptional tool was most likely complete when lost or stored at the Late Archaic campsite.