Three primary plant communities are frequently found on the Caja del Rio plateau: pinon-juniper savanna, pinon-juniper woodland, and Great Basin sage scrub. The most prevalent vegetative communities consist of a pinon (Pinus edulis) and juniper (Juniperus monosperma) overstory with a short grass understory. Tree densities often range between 100 and 300 trees per acre. Another large community consists of open grassland, with blue grama (Bouteloua gracilis), galleta (Pleuraphis jamesii), and various species of Stipa being the most common grasses. Common woody shrubs include chamisa (Chrysothamnus nauseosus), Apache plume (Fallugia paradoxa), four-wing saltbush (Atriplex canescens), and big sagebrush (Artemisia tridentata).