Minnesota is at the northeastern edge of a tallgrass prairie that once covered 400,000 square miles of North America. Today, less than one percent of that prairie remains. Of the 80 acres at Jeffers Petroglyphs, 33 are native prairie and 47 contain one of the first prairie recreations in Minnesota. Like all prairies, this landscape is a mixture of flowers and grasses. More than 100 species of prairie plants are found here, some of which are very rare. A federally threatened species, prairie bush clover, thrives at Jeffers Petroglyphs.
The prairies in this region developed during a warm and dry period 9,000 years ago, a few thousand years after the last glaciers receded from the area. Prairie grasses and flowers adapted to these conditions by forming extensive underground root systems. With this adaptation, the prairie was able to survive fires, which were sometimes started on purpose by people to draw buffalo to the renewed, richer, shorter, tender grass that follows a fire. During wet years, these fires kept water-hungry trees from taking over the grasslands.
Although the diet of American Indians consisted of a variety of plants, fish, insects, reptiles and mammals, buffaloes provided the essential dietary and raw materials needed to survive. They supplied food, clothing, bedding, shelter, fuel, tools, weapons, household utensils, personal or ceremonial adornment, and symbols of worship.
One buffalo provided hundreds of pounds of meat. Its tough, impermeable skin was ideal for making the mobile tipi, clothing, bedding, rope, shields, boats, bags, pipe holders and parchment for painted records. Tools were made from bone. Thread was made from sinew. Cups were made from the horn. The stomach was used as a container for water and, when propped upright with four sticks, it became a pot for cooking with heated stones. The bladder was used as a water container and as a bag to store food. Buffalo were grocery stores, hardware stores and clothing stores for the people on the prairie.
In addition to providing direct sustenance for the buffalo, the prairie offered American Indians foods such as prairie turnip, grass seeds and rose hips, the same foods eaten by early settlers of the 19th century. In the 20th century, prairies produced hay to fatten cattle, milkweed pods for food during droughts of the 1930s and milkweed seeds to fill life preservers during World War II.
Jeffers Petroglyphs site manager, Tom Sanders, describes the beauty and changing flora of the prairie. (2009).