Hundreds of ancient earth ovens used by First Nations dot traditional root gathering grounds

UBC Reports | Vol. 52 | No. 9 | Sep. 12, 2006

Exploring B.C.’s Black Holes

I discovered my first “black hole” 15 years ago. It was a large, circular depression — about four metres across and a metre deep — with a prominent, raised rim and it stood out in the dry grasslands of a valley I was surveying in the southern interior plateau of British Columbia. Excavations revealed a rock-lined basin filled with blackened sediments, burnt wood and charred plants, and copious amounts of fire–cracked rock (hence the nickname “black hole”).

This particular black hole turned out to be almost 2,000 years old.

What are black holes? They are the remains of ancient earth ovens used by First Nations people from throughout B.C. to pit cook a variety of wild root foods — a rich source of carbohydrate energy harvested in large quantities, steamed in earth ovens and stored for winter. Construction and repeated use of the ovens created permanent features on the landscape, massive basins and mounds up to eight metres in diameter. Hundreds dot traditional root gathering grounds, marking more than 3,000 years of continuous use.

For the past two summers, Prof. Brian Kooyman, of the University of Calgary’s Dept. of Archeology, and I have led groups of students to continue excavations at an archaeological site in the Hat Creek Valley, near Cache Creek, B.C. — a spot where generations of First Nations people have gathered for more than 2,000 years to collect and cook edible roots.

As a paleoethnobotanist, I study people-plant relationships by analyzing plant remains from archaeological sites. Black holes are highly visible and full of charred plants to recover and identify. Further, plant use traditions shared by contemporary First Nations elders can guide my interpretations of these ancient root-processing sites, blending perspectives from Western science and traditional ecological knowledge — two different but complementary ways of knowing — to produce a more complete picture of past plant use.

My goal is to create a detailed accounting of the species present at the site. Creating such a species list is an essential step in paleoethnobotany, but it’s just the beginning. The list might tell me whether I’ve recovered wood charcoal or seeds of wild berries. But it says nothing of the cultural use and significance of these species. For that, I turn to traditional knowledge systems, and specifically to the ethnobotanical evidence.

Many of today’s elders remember helping their grandmothers harvest and prepare wild roots for pit cooking. Their stories and recipes have taught me a great deal about the plants I find in ancient earth ovens and about the ovens themselves.

For example, Plateau peoples name hundreds of plants in their own languages. Prayers and protocols surround the harvesting and cooking of wild root foods, and these practices are reinforced by oral traditions passed between generations. Such insights challenge me to think about past people-plant relationships in new ways. Earth ovens — B.C.’s black holes — are not simply “camp kitchens” but symbols of a highly sophisticated system of wild plant food production developed by Plateau peoples over thousands of years.