Stipa grass, grama grass, and other grasses grow abundantly in certain parts of the Chisos Mountains. They supported the ranching industry that flourished here in the early 1900s. Today these grasses provide food for deer and smaller wildlife, and help hold fragile soil in place.
Periodic wildfires help to maintain this ecosystem of grasses and trees; grass fires return nutrients to the soil and create clearings for tree seedlings to grow. Without fires, brush accumulates and chokes out seedlings and grasses, changing the overall ecology of the mountains.