136 SALICACEAE (WILLOW FAMILY) 



to narrowly obovate, obtusish to abruptly acute at the apex, acute to semi- 

 cordate at the base, entire, light green and somewhat tomentose above, 

 pale yellowish-green and densely yellowish-tomentose to glabrate beneath, 

 not glaucous, 2-3.5 cm. long, 6-12 mm. wide; petioles 3-5 mm. long; stipules 

 none: aments numerous, often crowded, subglobose to oblong, 0.5-2 cm. long, 

 mostly about 1 cm. long: capsules ovate-lanceolate, subsessile, 5-7 mm. long, 

 densely gray- or white-tomentose ; styles 1-1.5 mm. long; stigmas medium. 

 S. desertorum. [S. stricta (And.) Rydb. Bull. N. Y. Bot. Gard. 1: 273. 1899.] 

 Wet places in the mountains above 2,000 m., fairly common; Colorado and 

 northward to the plains of Canada. 



22. Salix Candida Fluegge, Willd. Sp. PI. 4: 708. 1806. A low, branching 

 shrub, 2-10 dm. or more high; branches stout, divaricate, glabrous, light brown 

 or yellowish ; twigs densely white-tomentose : leaves linear-oblong to narrowly 

 oblanceolate or occasionally much broader, usually acute at both ends, mar- 

 gins revolute, entire, or rarely crenulate and glandular, dark green, dull and 

 thinly tomentose above, with deeply impressed veins, resembling sage leaves, 

 densely white-tomentose beneath, 3.5-8 or 10 cm. long, 0.7-2 cm. wide; 

 petioles short, tomentose; stipules very narrow, acute, glandular, tomentose: 

 aments on short leafy tomentose peduncles, the pistillate 1-3 cm. long, 1-1.3 

 cm. wide: capsule lanceolate, short-pediceled, white-tomentose, 6-8 mm. long; 

 scales obovate, white-woolly; styles reddish or orange, 1-1.5 mm. long; stig- 

 mas short, divaricate, notched. SAGE-LEAVED or HOARY WILLOW. Infre- 

 quent, in cold bogs; east of the Divide, from southern Wyoming to Alberta, 

 Saskatchewan, and eastward. 



23. Salix petrophila Rydb. Bull. N. Y. Bot. Gard. 1: 268. 1899. Stems 

 horizontal, creeping; branches erect, glabrous, brown or yellowish, 5-10 cm. 

 high: leaves broadly elliptical to obovate, abruptly acute to obtuse, entire, 

 deep green above, 'distinctly pale to subglaucous beneath, rather strongly 

 veined, 1.5-4 cm. long, 1-1.5 cm. wide, glabrate or glabrous; petioles slender, 

 yellow: staminate aments 1-2, the pistillate 2-4 cm. long, slender, lax at base: 

 capsules lanceolate, sessile, gray-tomentose, 4-6 mm. long; styles 1-1.5 mm. 

 long. S. arctica petraea Anders. Among rocks, alpine summits, above 

 3,500 m.; Colorado, Utah, and northward. 



24. Salix tenera Anders. 1. c. 288. Scarcely 5 cm. in height, from horizon- 

 tal creeping stems: leaves narrowly elliptical to obovate, acute at both ends 

 or sometimes obtuse at the apex, deep green and shining on both sides or 

 slightly paler beneath, very strongly nerved, 0.8-12 mm. long, 4-8 mm. wide; 

 petioles 2-3 mm. long: aments subglobose, few-flowered, the staminate 

 5-10 mm. in length, the pistillate 7-20 mm. long: capsules sessile, 4-5 mm. 

 long, gray-tomentose. Rare; alpine summits from Wyoming to Washington. 

 Perhaps only a variety of the preceding. 



IX. ARGENTEAE. Shrubs 1-3 or 4 m - high; twigs rather long, brownish or 

 yellowish, often lustrous and mostly pruinose: leaves narrowly oblong or ob- 

 lanceolate, acute, entire or subentire, densely silvery-sericeous or silvery- 

 tomentose beneath: aments sessile or very short-pedunculate, 1-4 cm. long: 

 stamens 2: scales brown or black, hairy: capsules small, silvery-sericeous, ses- 

 sile or short-pediceled; styles elongated. 



25. Salix subcoerulea Piper, Bull. Torr. Bot. Club 27: 400. 1900. Erect 

 shrub 1-3 m. high; twigs glabrous, usually covered with a dense bluish bloom: 

 leaves oblong-lanceolate or oblanceolate, acute or acuminate at the apex, 

 acute at the base, 2-5 or 7 cm. long, 0.8-2.5 cm. wide, entire or slightly 

 crenulate, green and sparsely pubescent above, densely covered with a fine 

 short silvery pubescence beneath; petioles 2-7 mm. long; stipules none, -or 

 occasionally very small and lanceolate on vigorous shoots: pistillate aments 

 sessile or short-pedunculate (peduncles sometimes 5 mm. long, with 1 or 2 

 small bract-like leaves al base), 2-4 cm. long, densely flowered; staminate 

 aments sessile, stout, 1-2 cm. long; stamens 2; scales brown or black, oblong, 

 ovate or obovate, acute or obtuse, thinly pilose: capsules ovate or ovate- 

 lanceolate, subsessile or short-pediceled, 3-5 mm. long, silvery sericeous; ped- 



