WILLOW FAMILY. 119 



veined, glabrate or densely short-silky beneath; catkins appearing before the 

 leaves, oblong or elliptic, % to 1 in. long, 5 to 7 lines thick, sessile; scales 

 black or black-tipped, covered with white hairs; stamens 2, conspicuously 

 exserted, filaments glabrous; ovary short-pediceled, white-silky; style none, stig- 

 mas broadly linear. — (S. nuttallii var. brachystachys Sarg.) 



Sierra Nevada, 4,000 to .10,000 ft., and seaward Coast Ranges, north to 

 British Columbia and east to the Rocky Mts. 



8. S. sitchensis Sanson. Velvet Willow. Shrub 5 to 12, or a tree up 

 to 25 ft. high ; leaves obovate to oblanceolate, rounded or shortly acute at 

 apex, entire, dark green and almost glabrous above, densely tomentose and 

 lustrous silky beneath, 2 to 5 in. long, 1 to 3 in. wide; stipules small, early 

 deciduous or on sterile shoots broad or orbicular, 4 to 6 lines long; staminate 

 catkins l 1 /! to 2 in. long; stamens 1, or exceptionally 2 and their filaments more 

 or less united ; pistillate catkins % to 2 in. long, in fruit 3 to 5 in. long ; bracts 

 covered with long white silky hairs; ovary silky, short-pediceled or sessile; 

 style elongated, stigmas short-oblong, entire or nearly so. 



California coastal region; Sierra Nevada, 5,000 to 7,000 ft.; far north to 

 Alaska. dHJffli 



2. POPULUS L. Poplar. 



Trees with scaly buds and caducous stipules. Leaves rather long-petioled, 

 broad. Winter buds covered by many scales. Catkins appearing before the 

 leaves, in ours pendulous ; scales fimbriate or lacerate, falling as soon as released 

 by the flowering elongation of the catkin. Stamens inserted on the surface of 

 a concave disk. Ovary seated on a collar-like disk ; style short ; stigmas 2 to 4, 

 narrow and elongated, or conspicuously dilated. Capsule 2 to 4-valved. Coma 

 of the small seeds long and conspicuous. — (Classical Latin name of the 

 Poplar.) 



Leaves deltoid-orbicular, 2 to 4 in. broad, broader than long, yellowish green, alike on 

 both faces 1 . P. fremontii. 



Leaves ovate, 2^2 to 7 in. long, longer than broad, ovate, dark green above, rusty or 

 sil very beneath 2. P. trichocarpa. 



1. P. fremontii Wats. Common Cottonwood. Handsome tree commonly 

 40 to 90 ft. high with massive crown of spreading branches; leaves triangular 

 or roundish in outline, 2 to 4 in. broad, broader than long, the margin crenate 

 except at the abruptly short-pointed apex and the truncate or subcordate base; 

 staminate catkins 2 to 4 in. long, densely flowered; stamens about 50 to 70; 

 pistillate catkins loosely flowered; stigmas 3 or 4, roundish; capsules on pedi- 

 cels 2 lines long ; seeds copiously provided with long white hairs which soon 

 involve the catkin in a soft cottony mass. 



Living streams: Great Valley, Sierra Nevada foothills, South Coast Ranges 

 to Southern California. Rare in North Coast Ranges or mostly absent (Jep- 

 son, Trees Cal., p. 142). 



2. P. trichocarpa T. & G. Black Cottonwood. Tree 40 to 125 ft. high 

 with a broad head of upright branches; leaves broadly or narrowly ovate, finely 

 serrate, truncate or heart-shaped at base, acute or tapering to a point at 

 apex, 2 1 /> to lOV-j i n - long, lustrous green above, rusty-brown beneath when 

 young but at length whitish; staminate catkins 1 to 2 or eventually 5 in. long; 

 stamens 40 to 60 on a slightly one-sided disk; pistillate catkins loosely flowered, 

 2% to 3 in. long, in fruit 4 to 10 in. long; stigmas 3, dilated and deeply lobed; 

 capsules nearly sessile. 



Along streams: Sierra Nevada, at middle altitudes; Coast Range valleys 



