80 



SILVA OF NORTH AMERICA. 



CONIFERS. 



elastic leaves from four to nine inches in length and persistent on the glaucous stouter branches for 

 from six to nine years, yellow-green staminate flowers, short-stalked usually purple cones from five to 

 twelve inches in length, their scales armed with stout or slender prickles, usually hooked backward, and 

 seeds often nearly half an inch long, with larger wings and from seven to eleven cotyledons. This tree 

 forms a considerable forest on Scott Mountain in northern California, where it was discovered in 1850 

 by John Jeffrey, and occurs on Snow Mountain, one of the highest peaks of the Coast Range in Lake 

 County ; * it is abundant in the great forests of Yellow Pine which cover the slopes of the valley of the 

 upper Pitt River, growing to a large size on the margins of arid volcanic table-lands and Artemisia- 

 covered plains ; it is the common form in the great yellow Pine forests which clothe the eastern slope 

 of the central and southern Sierras, where it probably grows to its largest size, attaining a height of 

 from one hundred to nearly two hundred feet, with a tall massive trunk from four to six feet in diameter 

 covered with bright cinnamon-red bark deeply divided into large irregular plates ; it is also common at 

 high elevations on the western slope of the Sierras, where it is able to maintain a foothold on the most 

 exposed and driest ridges and cliffs, 2 here being often almost reduced to a shrub with stout semi- 

 prostrate branches, or, when sprung from seeds washed down by mountain torrents, attaining fair 

 proportions in sheltered canons at lower altitudes ; it abounds, too, on the San Bernardino and San 

 Jacinto Ranges up to elevations of eight thousand feet above the sea and on the Cuyamaca 

 Mountains ; and in northern Lower California it forms extensive forests on the San Rafael Mountains 

 east of Todos Santos Bay at elevations between four and six thousand feet, 3 and finds its most 

 southerly home on high dry slopes of Mt. San Pedro Martir, near the middle of the peninsula. 4 



A form 5 with nearly black furrowed bark or with bright cinnamon-red bark broken into large 



the other forms of Pinus ponderosa ; but the two are united by 

 many intermediate varieties, which often make it impossible to dis- 

 tinguish the two trees as they grow together. Trees of such inter- 

 mediate characters are abundant in the Pine forest on the head of 

 Pitt River, near the shores of Lake Tahoe on the eastern slope of 

 the Sierra Nevada, and on the San Bernardino and San Jacinto 

 Mountains, where forests of trees occur which may be as well 

 referred to one form as to the other. 



1 K. Brandegee, Zoe, iv. 176. 



2 Garden and Forest, iv. 457, f. 73. 



8 This is the Pinus Jeffreyi, var. peninsularis, of Lemmon (Rep. 

 California State Board Forestry, ii. 74 [Pines of the Pacific Slope'] 

 [1888] ; West-American Cone-Bearers, 35. — Steele, Proc. Am. 

 Pharm. Assoc. 1889, 239 [The Pines of California']), who describes 

 it as growing only on the loose de'bris of white granite, and attaining 

 a height of from one hundred and fifty to two hundred feet, with 

 a spire-like fusiform habit. " The bark is grayish or drab, thick, 

 hard, deeply fissured. . . . Yearling cones very large, an inch to 

 an inch and a half long, elliptical, and purple. Mature cones abun- 

 dant, many years' crops lying under the trees, all large, broadly 

 ovate, six to eight inches long, truncate at base, mahogany-colored, 

 with prickles strongly deflexed " (Lemmon, Rep. California State 

 Board of Forestry, I. c. 101. — Orcutt, Garden and Forest, v. 183, 

 f. 28, 29). 



4 Brandegee, Zoii, iv. 201. 



5 Pinus ponderosa, var. scopulorum, Engelmann, Brewer Sf Watson 

 Bot. Cal. ii. 126 (1880). —Coulter, Man. Rocky Mt. Bot. 432.— 

 Lemmon, I. c. 73, 78; West-American Cone-Bearers, 34. — Watson & 

 Coulter, Gray Man. ed. 6, 734. — Beissner, Handb. Nadelh. 263. — 

 Masters, Jour. R. Hort. Soc. xiv. 238. — Hansen, Jour. R. Hort. 

 Soc. xiv. 384 (Pinetum Danicum). — Merriam, North American 

 Fauna, No. 7, 339 (Death Valley Exped. ii.). — Coville, Contrib. U. S. 

 Nat. Herb. iv. 223 (Bot. Death Valley Exped.). — Britton & Brown, 

 El. Fl. i. 51, f. 113. 



Pinus resinosa, Torrey, Am. Lye. N. Y. ii. 249 (not Aiton) 

 (1820). — Winchell, Ludlow Rep. Black Hills, Dakota, 68. 



Pinus macrophylla, Torrey, Sitgreaves' Rep. 173 (not Engel- 

 mann) (1853). 



Pinus ponderosa, Engelmann, Am. Jour. Sci. ser. 2, xxxiv. 332 

 (not Douglas) (1862). — Watson, King's Rep. v. 331. — Porter & 

 Coulter, -FY. Colorado; Hay den's Surv. Misc. Pub. No. 4, 129. — 

 Gard. Chron. u. ser. ix. 796, f. 138. — Coulter, Contrib. U. S. 

 Nat. Herb. ii. 554 (Man. PI. W. Texas). 



Pinus scopulorum, Lemmon, Garden and Forest, x. 183 (1897). 

 Pinus ponderosa, var. scopulorum, is a tree, usually from fifty to 

 seventy-five feet in height, but under favorable conditions one hun- 

 dred or one hundred and twenty-five feet tall, with a trunk two or 

 three or rarely four feet in diameter, and stout branches which in 

 youth form a broad open pyramid and in old age a round- topped 

 picturesque head. The variations in the bark are best seen in 

 northern New Mexico and Arizona, where among trees standing 

 side by side, of the same size and probably of the same age, some 

 have bright cinnamon-red bark broken into large plates, and others 

 nearly black furrowed bark. On young trees of this variety the 

 bark is usually dark and fissured, and in other parts of the country 

 this form of bark may be found on half-grown individuals ; but I 

 have seen it on large trees only on the Colorado plateau ; and here 

 it should perhaps be considered a juvenile character, as the bark of 

 the very largest trees is commonly cinnamon-red and broken into 

 plates. 



The Yellow Pine of Nebraska, Colorado, and Texas is certainly 

 distinct in its habit, in the length of its leaves, which are often in 

 clusters of two, and in the size of its cones, from the trees of the 

 western slope of the California Sierra Nevada ; but the two forms 

 mingle and are often indistinguishable in the region west of the 

 summits of the northern Rocky Mountains, and it is probably best 

 to consider this Yellow Pine one of the numerous forms of the 

 polymorphous and widely distributed Pinus ponderosa. 



