Pinus io 57 



southern California and of northern Lower California. It grows in a very dry climate, 

 the rainfall varying from 16 in. in the northern part of its area to 5 in. in the southern 

 part, while the temperature is extreme, ranging from a minimum of 2 Fahr. in the 

 Sierra Nevada to a maximum of 122 Fahr. in the Mojave desert. It occurs in arid 

 situations on foothills, gravelly slopes, and rocky elevations, at elevations of 3800 to 

 6800 ft. in Utah and Nevada, and 4000 to 9500 ft. in the San Bernardino mountains, 

 where the tree is abundant. It usually grows in mixture with other species, but 

 frequently forms pure open woods over large areas. In Arizona it is associated with 

 Pinus edulis, Juniperus monosperma, J. pachyphloea, and Cupressus arizonica. In 

 Utah its chief companion is Juniperus utahensis, while in southern California it 

 occurs sparingly in the chaparral formations, together with J. californica, oaks, and 

 tree yuccas. Occasionally it grows with Abies concolor or with Pinus Jeffreyi. 



P. monophylla was considered by Newberry ' to be a depauperate or desert form 

 of P. edulis, which has a more easterly distribution. Sir Joseph Hooker, however, 

 was convinced that the two species are distinct, and that two-leaved forms of P. 

 monophylla are not identical with P. edulis. The latter has dull leaden grey foliage, 

 whereas that of P. monophylla is glaucous with a silvery sheen. P. monophylla is 

 the stronger plant of the two, and cannot be regarded as depauperate. 



This peculiar pine was discovered by Fremont in 1844, and was introduced 

 into Europe by Hartweg 2 in 1848. It is extremely slow in growth, a specimen 5% 

 in. in diameter from Utah, which was examined by Sargent, showing 113 annual 

 rings. It is occasionally seen in botanic gardens, there being a healthy specimen 

 about 5 ft. high at Cambridge. Hooker, writing in 1886, mentions a tree at Kew, 

 no longer living, which was only 6 ft. high, though it was twenty years old, yet he 

 considered it to be faster in growth than P. edulis. The best specimen we know of 

 in England is a tree at Dunburgh House, Beccles, which is about 14 ft. high, and 

 bore a single cone in 1908. Another at Paul's Nursery, Cheshunt, was 13 ft. high 

 in 1909. Seedlings received from Kew have proved hardy at Colesborne, though they 

 grow very slowly. Elwes saw a specimen, about 20 ft. high, in the Botanic Garden 

 at Montpellier, which bore young and old cones with good seed in 19 10. 



The seeds are the staple food of the Indians in Nevada, and are highly 

 esteemed by white people, who eat them roasted. The timber is used for firewood, 

 and is also largely employed in the mines. (A. H.) 



1 Bull. Torrty Bot. Club, xiii. 183 (1886). M. E. Jones, in Zoe, iii. 307 (1893), states that the leaves of P. monophylla 

 are much more robust and vigorous than those of / '. edulis. 

 * Journ. Horl. Soc. iii. 226 (1848). 



