618 SALICACE A SALIX 
mas nearly sessile. Common on stream-banks, eastern Washington to 
California and New Mexico. 
§ 2 Shrubs or small trees. Leaves linear to lanceolate, re- 
motely denticulate to entire. Aments borne on short lateral 
leafy branchlets, often clustered. Scales pallid, somewhat decid- 
uous. Stamens only 2. ap) 
S. fluviatilis Nutt. Sylva i, 73- S. longifolia Muhl. not of Lam. A 
much branched shrub 2-12 feet high forming thickets, or sometimes tree- 
like and 20-30 feet high: leaves linear-lanceolate to linear-oblong, 2-4 
inches long, silky-pubescent when young, glabrous when mature, entire or 
sparingly dentate, acuminate, shortly petioled: stipules minute or none: 
aments linear-cylindric; the staminate dense, 1-2 inches long, sometimes 
polygamous; stamens 2; filaments distinct, pubescent; pistillate looser, 
about 2 inches long in fruit, their scales deciduous: stigmas broad, sessile: 
capsule ovoid-conic, glabrous or silky, about 2 lines long. In moist soil 
along streams inthe interior, Brit. Columbia to California and east to 
Missouri and Kentucky. 
Var. tenerrima. S. longifolia var. tenerrima Henderson. “ A 
smooth shrub 6-12 feet high with light bark up to the youngest branches: 
leaves shorter and narrower, 4-1 line wide on fructiferous branches, 1-2 
lines wide on the sterile, glabrous or very early glabrate: pedicels slightly 
longer: capsule glabrous: scales glabrous save for the slightly ciliate edges. 
Shaded rocky banks of mountain rills Elmore Co. Idaho. ”’ 
S. argophylla Nutt. Sylva i, 71. S. Hindsiana Benth. A shrub or 
small tree 3-15 feet high forming thickets but not growing in clumps, each 
stem being distinct from any other: leaves narrowly lanceolate, 2-3 inches 
long, closely sessile, entire or rarely minutely and remotely denticulate, ap- 
pressed silky-pubescent both sides: stipules, obsolete, or on young vigorous 
shoots sometimes minute ones occur ; aments 1-2 inches long, on short leafy 
branchlets appearing after the leaves in spring and intermitently all sum- 
mer; staminate aments 1-3 at the ends of the branchlets, the scales oblong, 
obtuse, glabrous on the back, crisp-hairy on the margins and toward the 
base, erose toward the apex: stamens 2, the filaments densely hairy: 
pistillate aments rather loosely flowered, 1-3 inches long, the lanceolate 
acutish scales subpersistent, woolly except near the apex: capsule lanceo- 
late, appressed silky when young, closely sessile: stigmas sessile. Along 
rivers, Brit. Columbia to California. 
S. exigua Nutt. 1. c. A low shrub or small tree 5-15 feet high: usual- 
ly with a single trunk, rough bark and glabrous twigs: leaves narrowly lan- 
ceolate to oblanceolate, acute,, subentire, 1-5 inches long, glabrate above, 
sparingly appressed-silky beneath, closely sessile: stipules none or minute: 
aments on leafy branchlets, solitary or 2-4 together: staminate aments 1-2 
inches long, slender, the scales lanceolate, acute: capsule becoming glabrous, 
sessile: stigmas sessile. Along streams, Washington to California 
S. sessilifolia Nutt. 1. c. Shrubby or often tree-like 6-30 feet high, 
oung shoots very leafy, hoary-pubescent, becoming glabrous and brown: 
eaves membranaceous, elliptical, acute at both ends, 1-5 inches long 1-2 
inches wide, closely sessile, obscurely and remotely denticulate, hoary 
with rather long pubescence when young, glabrous when mature: aments 
borne upon lateral leafy shoots, 3-4 inches long often 3 together, very 
densely flowered: scales oblong or obovate, rounded or retuse at the apex, 
nearly or quite glabrous: stamens 2: lower half of filaments very hairy, upper 
half minutely puberulent: pistillate smaller, the scales narrower: capsule 
lanceolate, silky-pubescent when young, becoming nearly glabrous at maturity 
