As a codominant with juniper species (Juniperus spp.), pinyon  trees predominate in pinyon-juniper woodlands of the semidesert zone,  which cover nearly 24.7 million ha (61 million acres), extending from  Texas to California (9). Woodlands in which pinyon is the major pine  species cover about 14.9 million ha (36.9 million acres) in Arizona,  Colorado, New Mexico, and Utah. Outliers in California, Oklahoma, Texas,  and Wyoming contribute a relatively insignificant acreage to the total  (48). However, the outlier in California has been considered a population  of 2-needled individuals of single-leaf pinyon (Pinus monophylla),  and more recently, a new species, California single-needle pinyon (Pinus  californiarum) (5,44).

     
- The native range of pinyon.