The Pedernales Cuts a Stair-Step Valley Near Stonewall

Near Stonewall, the Pedernales runs beside the LBJ Ranch through a valley that is rough at the edges and flatter toward the middle. The river valley cuts through the Llano Uplift, between the Edwards Plateau and the central Hill Country.

Limestone caps many of the hills, with older sandstones and shales below. Those layers weather at different rates, leaving slopes with a stair-step or benched look. Ashe juniper and oak woodland cover much of the shallow, rocky ground.

The river does not keep a fixed edge. Frequent floods erode its banks, shift channels, and carry soil downstream. In 2002, the National Park Service began keeping cattle away from part of the bank so riverside plants could return and help hold it. Around the ranch, the history sits inside a landscape that is still being shaped by rock, water, and flood.