The status of this vegetation type has been upgraded from "Special Stands" (as it was cited originally in the 2009 book, A Manual of California Vegetation, second edition ) to a full alliance, subsequent to classification analyses of surveys for the Mojave region (Evens et al. 2014).

Pinus edulis is a two-needle pine and occurs primarily in the Colorado Plateau of the southwestern United States. Plants grow as low, bushy trees to 17 m tall and attain ages of 500-1000 years. Trees begin bearing cones by 25 years of age. Seed production is cyclic, with heavy production every 5-7 years. Animals disperse and cache the short-lived seeds. The partial shade of shrub crowns facilitates seedling establishment. In time, the pines overtop the nurse plants. P. edulis is an obligate seeder and does not sprout after fire (Anderson 2002b).

California populations of two-needle pinyon are at the western edge of its distribution. However, botanists have disagreed about the nomenclatural and taxonomic status of these trees. Some botanists consider them as the two-needle species of P. edulis, the Colorado pinyon. Others consider them as a two-needle form of P. monophylla, as P. m. ssp. fallax, the Arizona single-leaf pinyon, or as a two-needle subspecies of P. californiarum, as P. c. ssp. fallax. See the Lanner (1999) review. Regardless of how these pines are treated taxonomically, they are an important component of the California flora. P. edulis is recognized as a rare CNPS list 3.3 plant. Additional work is needed to clarify boundaries between this alliance and the Juniperus spp. alliances that may have scattered pine trees (NatureServe 2007a).