134 SALICACEAE (WILLOW FAMILY) 



VI. COMMUTATAE. Shrubs 1~4 m. high; stems densely caespitose; twigs dark 

 brown, lustrous: leaves oblanceolate to obovate-oval or elliptic-oval, entire 

 or shallowly serrulate, densely to thinly villous-tomentose , at least above, stip- 

 ulate: aments on leafy peduncles (sessile in No. 16), precocious or coctaneous: 

 scales fuscous, broad, obtuse, villous: capsules ovate or rostrate, glabrous or 

 tomentose; pedicels 0.5-1.5 mm. long; styles 1-1.5 mm. long (except in No. 18). 



Leaves glabrate above, glabrous and glaucous beneath, crenate or serru- 

 late. 



Aments sessile 16. S. monticola. 



Aments leafy-pedunculate 17. S. Barclay!. 



Leaves densely villous-tomentose to glabrate on both sides, dull green 



beneath. 18. S. Wolfii. 



16. Salix monticola Bebb in Coult. Man. 336. 1885. Shrub 3-6 m. high; 

 twigs rather stout and divaricate, usually glabrous, deep reddish-brown, 

 lustrous: leaves at first oblanceolate, obovate or oval, finally more elliptical 

 or oblong-elliptical, acute or abruptly short-acuminate at the apex, usually 

 narrowed and rounded at the base or sometimes subcordate, 5-7 or more cm. 

 long, 2-4 cm. wide, crenate-serrulate, dark green above, subglaucous to glau- 

 cous beneath, glabrous or thinly puberulent or pubescent above, especially 

 on the pale yellow midrib and the primary veins, strongly reticulate beneath ; 

 stipules large, ovate or semicordate, acute, serrate: buds large: aments 

 sessile, stout, naked or the pistillate with a few broad bracts at the base, 

 2-3 cm long, the pistillate becoming 3-5 cm. long in fruit; scales dark, 

 obovate-oval, obtuse, densely villous with long white hairs: capsule glabrous, 

 sessile or subsessile, rostrate, rufescent, 5-7 mm. long; styles 1-1.5 mm. long. 

 (S. padifolia Rydb. not Anders.; S. padophylla Rydb. 1. c. 28: 499. 1901). 

 Common at high elevations, 2,400-3,500 m. ; New Mexico to Montana and 

 Alberta. 



17. Salix Barclay! Anders. 1. c. 125. Shrub 1-4 m. high; twigs short, stout, 

 divaricate, blackish, tomentose to glabrate: leaves ovate-lanceolate to oval 

 or obovate, acute or cuspidate at the apex, cuneate to rounded at the base, or 

 cordate on vigorous shoots, 3-7 cm. long, 1.5-2.5 or more cm. wide, crenate- 

 serrulate, the glandular teeth inflexed, or subentire, thinly tomentose above, 

 especially on the midrib and veins, becoming glabrate, glabrous, reticulate 

 and mostly glaucous beneath; stipules large, ovate-acuminate, serrate: aments 

 stout, on leafy peduncles 1-3 cm. long; staminate aments 1-3. and the pistil- 

 late 2-6 cm. long, 1.5 cm. wide; scales fuscous, mostly acute, thinly to densely 

 villous with long hairs: capsules glabrous, or sometimes thinly sericeous, 

 greenish, rostrate, 5-7 mm. long; pedicels 0.5-1 mm. long; styles 1-1.5 

 mm. long. (S. conjuncta Bebb, Bot. Gaz. 13: 111. 1888). High elevations, 

 mountains of Colorado and southeastern Wyoming to Oregon, Washington, 

 and Alaska. 



18. Salix Wolfii Bebb, Bot. Wheeler Exp. 241. 1878. Low shrub 6-10 dm. 

 high; twigs chestnut, leafy, the younger yellowish, lustrous: leaves oblanceo- 

 late or rhomboid-oblanceolate, or elliptical, acute at the apex, rounded at the 

 base, 2-4.5 cm. long, 8-13 mm. wide, entire, dull green and silky-villous with 

 shining hairs on both sides, becoming somewhat glabrate; petioles yellow, 

 villous; stipules small or wanting: peduncles short, bearing several leaf-like 

 bracts which often exceed the ament; pistillate aments 1-2.5 cm. long, sub- 

 globose to oblong, densely flowered; staminate aments 0.5-1.5 cm. long; 

 scales dark, obovate, sparsely long-villous : capsules glabrous, greenish or 

 rufescent, 3.5-4.5 mm. long; pedicels about 0.5 mm. long; styles variable, 

 0.5-1 mm. long. S. desertorum Wolfii. At middle to high elevations; south- 

 ern Colorado to Wyoming and Idaho. 



18a. Salix Wolfii idahoensis Ball, Bot. Gaz. 40: 378. 1905. Leaves larger, 

 3-6 cm. long, 1-1.8 cm. wide, oblanceolate: aments longer, 1-3.5 cm. in 

 length; peduncles proportionate: capsules about 5 mm. long, greenish, thinly 

 tomentose. This includes most of the material called " S. (jlnnca rillosa " in 

 herbaria. Big Horn Mountains of north Wyoming to east Oregon and north 

 Idaho; abundant in the region of the Yellowstone National Park. 



