The Plains lay south and west of the Sandusky River, bounded by the Olentangy River on the east and Tymochtee Creek on the west. Local black prairie soils mark the extent of grasslands that were uncommon in the dense eastern forests. Bur Oak trees from the period of the Wyandot Indians survived because their thick bark protected them from the common prairie grass fires. This remnant of wilderness, Bur Oak Grove and Tall Grass Prairie, is protected from cultivation, which would destroy most of the native plant species.