120 Salicaceae — 
Subgenus COMMUTATAE—Shrubs, ‘rarely tree-like, about 1—5 m. high; 
twigs dark-brown, shining or hairy. Leaves lanceolate to oblanceolate, entire or shal- 
lowly serrulate, densely to thinly tomentose at least above; stipules present or none, 
Aments on leafy peduncles (ours), appearing with or before the leaves; scales fuscous 
or black, wide, obtuse, villous. Capsule ovate or rostrate, glabrous or tomentose; pedi- 
cels 0.51.5 mm. long; style 0.5—1.5 mm. long. 
A. Leaves lanceolate; scales of aments black. E. 
S. lemmoni Bebb 
AA. Leaves either ovate-lanceolate or else widest at or above the middle of the blade; 
scales of aments not black. 
B. Leaves glabrate above, glabrous and glaucous beneath, crenate or serrulate. W. 
QP ES S. barclayi Anders. (Barclay Willow) 
BB. Leaves quite hairy on both sides, not glaucous beneath. 
C. Stipules large, ovate. W.C. E. (S. commutata mixta; S. commutata denu- 
data.) S. commutata Bebb 
CC. Stipules small or none. 
D. Twigs ash-colored, hairy; pistillate aments 2.55 cm. long. E. 
S. macrostachya Nutt 
DD. Twigs yellow-brown, glabrous; pistillate aments |—2.5 cm. long. CES 
(S. glauca villosa for our region.) 
S. wolfii idahoensis Ball 
Subgenus ARCTICAE—Shrubs, erect or creeping, alpine or bog plants, |—1I5 
dm. high (except S. myrtilloides which may reach 4 m.); branches full of leaf-scars. 
Leaves small or medium, narrowly elliptical to oblanceolate, occasionally wider, entire, 
more or less tomentose or glabrous; stipules small or none. Aments appearing with the 
leaves, on short leafy peduncles; scales brown or brown-tipped, villous. Capsule ses- 
sile or short-stalked, gray- or white-tomentose; styles |—1.5 mm. long; stigmas notched. 
A. Erect shrubs, bog plants, alpine or low-land, 4 dm. or less high; mature leaves 
mostly 3—6 cm. long. W.C.E. (Apparently S. glaucops.) 
S. myrtilloides L. (Bog Willow) 
AA. Depressed or creeping shrubs, rock plants, alpine, less than | dm. high; mature 
leaves mostly 1—3 cm. long. 
B. Leaves 2—4 cm. long, pale beneath, broadly elliptical to obovate. E. 
S. petrophila Rydb. (Rock Willow) 
BB. Leaves 1—1.2 cm. long, deep-green or slightly pale beneath, narrowly ellip- 
tical to obovate. C. S. tenera Anders. (Small-leaved Willow) 
Subgenus ARGENTAE—Shrubs, |—12 m. high; twigs rather long, brownish or 
yellowish, often lustrous, mostly pruinose. Leaves narrowly oblong or oblanceolate, 
acute, entire or subentire, densely silvery-hairy beneath. Aments sessile or very short- 
stalked, 1—5 cm. long. Stamens |—2. Scales brown or black, hairy. Capsule small, 
silvery-hairy, sessile or short-stalked; style elongated. 
A. Twigs densely covered with a bluish broom, glabrous, brownish; stipules none or 
on vigorous shoots lanceolate. C. E. 
S. subcoerulea Pip. 
AA. Twigs not dense with bloom, either yellow or hairy; stipules none or on vigorous 
shoots lunate or reniform. 
B. Stamens 2; twigs yellow, glabrous; staminate aments 1.2—2.5 cm. long, their 
scales acute. E. S. bella, Pip. 

