508 TREES OF NORTH AMERICA 



primary veins, persistent until the end of their second summer; their petioles broad, 

 about \' long; stipules nearly triangular. Flowers solitary, sessile in the axils of 

 the clustered leaves, f long; calyx hoary-tomentose. Fruit: mature calyx-tube 

 almost ' long, nearly cylindrical, rather larger above than below, 10-ribbed, ob- 

 scurely 10-angled, slightly cleft at the apex, hoary-tomentose; akene pointed at the 

 ends, obscurely angled, chestnut-brown, \' long, covered with long pale or tawny 

 hairs; style 2'-3' long, generally contracted by 1 or 2 partial corkscrew twists. 



A resinous slightly aromatic tree, occasionally 40 high, with a short trunk some- 

 times 2^ in diameter, stout spreading usually contorted branches forming a round 

 compact head, and red-brown branchlets coated at first with pale pubescence, soon 

 becoming glabrous, frequently covered with a glaucous bloom, silver gray or dark 

 brown in their second year, and for many years marked by the conspicuous elevated 

 leaf-scars. Bark red-brown, divided by deep broad furrows, and broken on the sur- 

 face into thin persistent plate-like scales, becoming on old trunks V thick. Wood 

 bright clear red or rich dark brown, with thin yellow sapwood of 15-20 layers of 

 annual growth. 



Distribution. Dry gravelly arid slopes at elevations of 5000-9000 above the 

 sea; sometimes on almost precipitous cliffs and on rocky ridges as a densely branched 

 contorted shrub, with linear revolute leaves, and smaller flowers and fruits (var. 

 intricatus, M. E. Jones); mountain ranges of the interior region of the United States 

 from western Wyoming to the western slopes of the Rocky Mountains of Montana, 

 the Cceur d'Alene Mountains of Idaho, the Blue Mountains of Washington and 

 Klarnath County, Oregon, and southward through the Wasatch Mountains and the 

 ranges of the Great Basin to the eastern slopes of the Sierra Nevada, the northern 

 slopes of the San Bernardino Mountains, California, and to the mountains of northern 

 New Mexico and Arizona; most abundant and of its largest size on the high foothill 

 slopes of the mountain ranges of central Nevada at elevations of 6000-8000. 



4. Cercocarpus breviflorus, Gray. 



Leaves oblong-obovate to narrowly elliptic, acute or rounded and often apiculate 

 at the apex, gradually narrowed from above the middle and acute at the base, their 

 margins revolute, often undulate, and entire or dentate toward the apex, with few 

 small straight or incurved apiculate teeth, when they unfold coated with hoary 

 tomentum, and at maturity thick, gray-green on the upper surface, pale on the lower 

 surface, covered with soft pale hairs most abundant on the under side of the midribs 

 and primary veins, '-!' long and usually about \' wide; their petioles stout, tomen- 

 tose, ultimately sometimes light red, -and pubescent or nearly glabrous, \'-^' long; 

 stipules linear-lanceolate, tomentose, about half as long as the petioles. Flowers 

 appearing from March to May and often again in August, nearly sessile, solitary or 

 in pairs in the axils of the crowded leaves; calyx-tube slender, T V~i' l n g> coated on 

 the outer surface, like the short rounded lobes, with dense white tomentum. Fruit: 

 mature calyx-tube stalked, spindle-shaped, light red-brown, pubescent above, to- 

 mentose toward the base, deeply cleft at the apex, about \' long; akene nearly 

 terete, covered with long white hairs; style I'-l^' long. 



A tree, 20-25 high, with a long straight trunk sometimes 6'-8' in diameter, 

 erect rigid branches forming a narrow open or irregular head, and slender bright 

 red-brown lustrous branchlets marked irregularly by large scattered pale lenticels, 

 covered at first with a thick coat of hoary tomentum, villose or pubescent for two 

 or three years and ultimately ashy gray or gray tinged with red, the spur-like lateral 



