161 



is among the hardiest of the Conifers, and grows in the most arid imd 

 exposed sites, usually occupyiug southern exposures. It occurs at ele- 

 vations between 1,500 and 6,500 feet. It does not attain us large a size 

 in the Kocky Mountains as in the California Sierras, although in Mou- 

 taua sometimes reaching 100 feet iu height, and 6 to 7 feet in diameter. 

 The wood is quite resinous, of a reddish color, with a handsome grain, 

 and is largely employed for lumber, railroad ties, mining timber, and 

 somewhat for interior finish. 



Description: — Leaves iu threes (often in twos), 3 to 6 inches long, brush-like at the • 

 ends of the brauchlets; x^ersistent three years. Cones 2 to 8 inches long (or more), 

 gray-browu, with stroug prickles. Bark very thick, in old trees, 3 to 4 inches. 



8. — OiiiiiUAiiuA Pine. {Finns Chihtialiiiana, Engelm.) 



Soniewhat rare and of limited range ; found on rocky slopes of south- 

 western Xew Mexico (extending into southern Arizona and northern 

 New Mexico), at elevations between 5,000 and 7,000 feet; 30 to 70 feet 

 high, li feet in diameter. Wood light and strong. 



Description. — Leaves mostly in threes (twos and fours also), 2| to 3-J inches longsj 

 cones ou stems ^ to f an inch long, 1^ to )l^ inches long; dark brown, with short del- 

 icate prickles. 



9.— Black Pine. LoDaE-PoLE Pine. Tamaeack. [Pinus Mur- 

 ray ana^ Balfour.) 



Eather abundant throughout the Rocky Mountain region, extendiu^ 

 westward and northward, but more common in the northern porbioH, 

 forming Inrge forests of pure grow^th. It is said, however, to attain its 

 greatest size in southern California— 60 to 100 feet, with a diameter of 

 over 3 feet.* \i. 



Usually found growing in slightly moist or dry gravelly soil between "^ 

 0.000 and 9,000 feet elevation. The wood is soft and light, not ualike 

 tliat of the White Pines ; employed to some extent for lumber, railroad 

 ties, and much for " lagging " in mines. 



Description. — Leaves iu twos, 1 to 3 inches long, but chiefly 2 inches, with fine 

 teeth. Cones 2 to 3 inches long, reilexed, and with delicate recurved prickles. Bark 

 very thin and scaly, grayish-browu. Crown conical. Resembles the Scrub Piue 

 {Pinus contorta, Dougl.). but distinguished from it by having longer and, wider leaves, 

 as well as by a much thinner bark. 



10.— White Spruce. Single Spruce. (Pkea alba, Link.) 



A large and important timber tree, growing in rather wet soil on the 

 borders of ponds and streams, reaching oyer 100 feet in height and 2 to 

 3 feet in diameter. In the Eocky Mountain region it occurs only in 

 northern Montana, and attains its greatest size in the Flathead region 



* When growing iu thickets it is often imperfectly developed, and is called " Lodge- 

 pole Pine ; " such trees sometimes being over fifty years old, with a diameter of not 

 more thau 6 to 8 inches. 



21738— Bull 2 11 



