This post is from field crew student Dorothy, reporting on her exciting first two weeks of fieldwork:
On the first day of field school I was reassured that we could stop digging once subsoil was reached–unless there was a “buried A-horizon.” Subsoil does not contain artifacts and it dates to before human occupation.
Buried A-horizons are not common. It can occur when soils are removed from another place– like a cellar, and then deposited on a former living surface. On the third day of excavations we discovered a buried A-horizon.
When we reached what we though was subsoil we excavated a bit further. Then we noticed a thin black layer underneath the subsoil which extended through the entire unit. We took off the layer of subsoil to reveal the ashy black layer that covered the unit and were able to determine that the subsoil had been redeposited when they constructed the cellar for a double house at around the mid-1850s.
The builders of the house dug into the subsoil to create the cellar and placed it on top of the humus-like living surface in the back of the structure. On top of this redeposited soil we found materials related to the early occupation of the dwelling – where they tossed their trash – like bones, smoking pipe stems, and broken dishes. Finding a buried A-horizon in my first test unit was an amazing experience.