260 UNIVERSITY OF COLORADO STUDIES 



Eastern slope of Rocky Mountains from Alberta to western Texas, westward through 

 Montana to Nevada and California. It is the principal tree of the upper foothills of the 

 eastern slope in Montana. In Nevada it forms extensive forests. In Colorado and Wyom- 

 ing it is usually scattered in exposed situations at rather high altitudes but a few trees are 

 found on the bluffs west of Pawnee Buttes, Colo., at an altitude of 5,00c feet. 



Pinus edulis Engelm. Pinyon, Nut Pine. Leaves in bundles of 2, rarely 3; 

 dark green, curved, stiff, 2 to 4 cm. long. Cone when mature about the same length as the 

 leaves and nearly spherical; cone scales few, thick, spiny tipped. Seeds large, about the 

 size of a small white bean, the narrow wing of the seed remaining adherent to the cone 

 scale when the seed falls. 



A small or medium-sized tree, much branched and shrublike. Bark rather thin; that 

 of young branchlets orange colored, becoming at length gray or brown. Wood rather 

 durable; specific gravity 0.6388; brittle, close grained. Used for fuel and fencing and 

 sometimes for preparation of charcoal. In western Texas it has been sawed for lumber. 

 The large, edible seeds, known as "pinyon nuts," collected by Indians, are on sale by fruit 

 dealers in the towns and cities of Colorado. 



Eastern foothills of the outer range of the Rocky Mountains from near the Palmer 

 Lake divide south to western Texas and west to Arizona and southwestern Wyoming. 

 In places it forms open forests with the rock pine; mixed with junipers it is common on the 

 hills and table lands of western Colorado. It does not extend to very high altitudes. 



Pinus scopulorum (Engelm.) Lemmon. Rock Pine. Leaves in bundles of 

 two or three, variable as to number even on the same tree; stout, dark yellowish green, 

 often in bottle-brush arrangement at the ends of naked branches; 8 to 15 cm. long. Cone 

 6 to 9 cm. long, the cone scales each with a stout sharp prickle. The young cones are erect 

 the first summer; when fully grown they are horizontal or slightly declining. 



A handsome spreading tree, the largest of our pines, with thick, deeply-furrowed, red- 

 dish bark becoming very thick on old trees. Wood hard and strong but differing greatly 

 in quality; where abundant it is sawed into lumber or used for railway ties and mine tim- 

 bers. The specific gravity is 0.4619. 



Hills and ridges of western Nebraska to Rocky Mountain region and from Montana to 

 Arizona and New Mexico. 



On account of its resistance to drought this tree should be a valuable one for planting 

 in semi-arid districts. The large seeds germinate freely and the trees are easily grown 

 when given reasonable care. Sometimes called "yellow pine" or "blackjack. " 



Pinus murrayana " Oreg. Com." Lodgepole Pine. Leaves in bundles of 2, 

 yellow-green, 3 to 6 cm. long. Cone about the same length as the leaves, very persistent, 

 often remaining attached three or four years after ripening; cone scales with short, sharp 

 prickles. 



A tall, straight tree, generally growing in dense groves on north slopes in the higher 

 foothills. The trees have been considered of little value for lumber but they are certainly 

 most useful in holding the soil and in protecting snow from too rapid melting. Seeds of 

 this pine, unlike those of most species, retain their vitality for a number of years. Burned 

 districts become reseeded by the opening of the cones which takes place on account of the 

 heat produced by the fire. Wood rather light and soft, not durable; specific gravity o . 4096. 

 Used to some extent for ties, mine timber and fuel when better wood is not available. 



