Fire is a natural process in the ponderosa pine forest. Both plants and animals have long been adapted to its presence. However, studies show that the ponderosa pine forest along the north rim of Walnut Canyon has changed considerably during the last century. Prior to 1890, the forest experienced a low-intensity fire every 4 to 8 years, and was composed of fewer, larger pine trees clustered in isolated stands with an open understory of grasses, wildflowers, and non-woody plants. The forest was open and park-like, with a vigorous mix of old and younger plants.
For more information:
Fire in Southwestern Ponderosa Pine Forests: a Bird's-Eye View.
Assessment of Forest Health in the Southwest, USFS
Did You Know?
The original Walnut Canyon Visitor Center was built from local stone by the Civilian Conservation Corps in 1940. It's still there, as part of the expanded building in use today.