Finally Moving Some Dirt

After 6 weeks of slow, laborious hand excavation in Delaware, we brought in a backhoe and uncovered as much of our sites this morning as we had in the whole project so far. Sometimes when I tell people on airplanes what I do for a living, they say, "Archaeology, that seems so tedious." I usually respond, "no, these days we usually dig with giant earth-moving machines."

Actually, archaeologists really do sometimes dig with toothpicks and brushes, as well as trowels, shovels, backhoes, and even bigger machines. A big part of the skill of modern archaeology is digging with the right tool at the right time. The key variable is the amount and type of information present in the site. If the exact placement of small objects is of importance, because the site is stratified or remarkably intact, you dig with small tools; if it is important to recover fragile items (such as soft bone) intact, then you dig with soft tools made of wood or plastic. If you are dealing with mixed deposits where everything fragile is already long gone, there is little point is using anything smaller than a backhoe.

The sites we are working on now are all in plowed fields. This means that everything within reach of the plow has already been mixed about and pulverized. On such sites we usually dig a sample of the plowed soil with shovels and put it through a screen to recover artifacts -- how much depends on how interesting the artifacts are, but 1% is typical. Then we use heavy machinery to remove the plowed soil from large areas to search for intact layers or "features" -- storage pits, post holes, wells, cellars, and so on -- the survive intact beneath. Here my crew is investigating a soil stain that turned out to be a very shallow and probably natural pit.