WHITE PINES OF WESTERN NORTH AMERICA 



221 



Southwestern White Pine (P. stvobiformis) 



This species has been the source of considerable taxonomic contro- 

 versy since its discovery. Synonymous names are P. flexilis var. reftexa 

 Engelm. and P. ayaaahuiie var. brachyptera Shaw. Southwestern white pine 

 is distributed from southern Colorado and extreme southern Utah through 

 Arizona, New Mexico, and western Texas in the U.S.A. and Sonora, 

 Chihuahua, Coahuila, Sinaloa, Durango , Zacatecas, Nuevo Leon, and 

 Tamaulipas to San Louis Fotosi in Mexico (Critchfield and Little, 1966; 

 Map 8) . 



Individual trees of the species are quite variable depending on the 

 conditions under which they grew. Trees on exposed sites often have 

 multiple-stemmed crowns or broad crowns with upturned branches. On more 

 protected sites where they are competing with one another and with other 

 species the trees are usually single stemmed and of a conical shape 

 (Fig. 6) . Single, mature specimens may be 4 feet or more in diameter 

 and 100 feet tall (Loock, 1950; Sargent , 1897) . The species is harvested 

 along with other species in timber sales in Arizona and New Mexico. 

 In Mexico it is used for furniture, pattern -making, and other interior 

 uses (Loock, 1950). 



Figure 6. Open-grown Pinus 

 stvobiformis near Springerville, 

 Arizona (photo courtesy J. W. 

 Andresen) . 



Southwestern white, pine is not planted commercially in the United 

 States. It has been tried in mixed plantations in the Union of South 

 Africa and does well where conditions are favorable (Loock, 1950). 

 Streets (1962) reported that individuals in the best South African planta- 

 tion averaged 34 feet in height and 8 inches in diameter 16 years after 

 outpl anting. 



