This summer work on a new trench has been started. The dirt is removed by trowel in 5 cm layers. The dirt is sifted in order to find items of interest to the researchers. Dave told me that to the trained eye it is generally easy to tell if a stone fragment has been chipped off by human actions (a product of tool making, for example) or other means. Measurements taken from these fragments can help the development of an understanding of what was going on in this location in the past.
Location: Malheur County, Oregon