DEER LODGE — Most people think of archaeology as the study of artifacts such as shards of pottery, tools, and arrowheads.
However, an archaeological dig in 2011 at Beaver Creek Rock Shelter near Nelson, east of Helena, led Darla (Lease) Dexter to study pollen found at the site.
Dexter, a 1994 graduate of Powell County High School in Deer Lodge, became interested in archaeology while taking a Native American Studies class with Lauri Travis, at Carroll College in the fall of 2011.
Last May she joined archaeologist and anthropologist Travis and others for a two-week dig. The Beaver Creek Rock Shelter was used by Indian tribes for more than 2,000 years as a temporary shelter for two or three people at a time, so fire hearths, bones, shells and rock flakes chipped off during the shaping of arrowheads were found.
Dexter was surprised some of the artifacts were three to four inches from the surface.
“I was expecting things to be much deeper. I didn’t know how long the earth takes to bury something when there are no major environmental changes like floods,’’ she said.
Pollen is of interest to archaeologists because they are looking for any climate changes that may have dictated human behavior, Dexter said. For example, when the climate supports plants with berries, the people will eat the berries. If there are no “easy meals,” they will turn to other sources of food.
Dexter collaborated with Travis and with Carroll’s librarian/botanist Kathy Martin, who called her a “great student” to write a paper about the pollen findings. Her paper, “Late Holocene Plant Use at Beaver Creek Rock Shelter,” is expected to be published in an upcoming edition of a Montana archeological journal.
The pollen became interesting for her paper, Dexter said, because the lab discovered pollen types only in the layers with signs of human occupancy, such as fire hearths.
“This is important,” Dexter said, “because it tells us that the plants were important enough to have been brought in by the people. My research was to try and find out why they brought the plants with them. Archaeologists often assume that plants were brought into shelters for food, but our research showed that the majority of the uses were medicinal.”
The microscopic pollen of five different plant families was found in dirt samples. Dexter took the plant families and matched them with 61 Montana native plant species. Martin took Dexter’s list and researched their native habitats in Montana. Eleven of the plants were found outside of Lewis and Clark or adjacent counties indicating those plants were brought from a greater distance.
Dexter said the lack of facts about trade routes and boundaries made her study difficult, but the use of ethnographical literature, based on oral traditions, helped determine each plant’s use.
Dexter graduated from Carroll College earlier this month “with distinction” and a bachelor’s degree in elementary education. She received an award for scoring in the top 15 percent in the nation on the PRAXIS II test, a content knowledge assessment covering many different subject areas that education majors are required to take for licensure.
Dexter is the daughter of Milt and Lindy Lease of Deer Lodge. She is married to John Dexter and has two children, ages 13 and 10.
— Freelance writer Pat Hansen may be reached via email at firstname.lastname@example.org