135 
SALICACE. SILVA OF NORTH AMERICA. 
SALIX CORDATA, var. MACKENZIEANA. 
Willow. 
LEavEs lanceolate or oblanceolate, acuminate, dark green on the upper surface, pale 
on the lower. 
Salix cordata x rostrata, Andersson, Proc. Am. Acad. iv. 
65 (1858); De Candolle Prodr. xvi. pt. ii. 252. 
Salix cordata, subspec. Mackenzieana, Andersson, Svensk. 
Vetensk. Akad. Handl. ser. 4, vi. 160 (Monographia Sal- 
icum) (1867). 
Salix cordata, » Mackenzieana, Hooker, Fl. Bor.-Am. ii. 
149 (1839).— Bebb, Brewer & Watson Bot. Cal. ii. 86 ; 
Coulter Man. Rocky Mt. Bot. 335; Garden and Forest, 
viii. 473. 
Salix cordata x vagans, Andersson, Ofvers. Vetensk. 
Akad. Férhandl. xv. 125 (Bidr. Nordam. Pilarter) 
(1858). 
A small tree, with a slender trunk,and upright branches forming a narrow shapely head. The bark 
of the trunk is smooth, pale and yellowish or gray in color. The branchlets are slender, marked with 
scattered lenticels, glabrous or slightly puberulous at first and often deeply tinged with red, but soon 
become yellow and lustrous and grow lighter colored in their second year, when they are more or less 
tinged with green. The buds are ovate, rounded on the back, compressed and acute at the apex, flat- 
tened by pressure against the stem, bright orange-color, and about an eighth of an inch in length. The 
leaves are involute in the bud, lanceolate or oblanceolate, gradually narrowed or wedge-shaped or 
rounded at the base, long-pointed and occasionally slightly faleate above the middle, and finely and 
obscurely crenately serrate,or entire; when they unfold they are reddish and pilose with caducous pale 
hairs, and at maturity are thin and firm in texture, dark green above, pale below, from two to three 
inches long and about half an inch wide, with slender yellow midribs and arcuate veins, obscure reticu- 
late veinlets, and thin yellow petioles about a third of an inch in length. The stipules are reniform, 
conspicuously venulose, about a sixteenth of an inch broad, and usually persistent during the season. 
The aments are oblong-cylindrical, densely flowered, erect, often more or less curved, about an inch and 
a half long, and terminal on short branchlets with leaves sometimes reduced to scales on the staminate 
plant; the rachis of the staminate ament is covered by a coat of thick white tomentum, and that of 
the pistillate ament is tomentose; their scales are oblong-obovate, acute, dark-colored, glabrous except 
at the base, and persistent under the fruit. The stamens are two in number, with elongated free 
glabrous filaments. The ovary is cylindrical, elongated, gradually narrowed into a slender style 
crowned by spreading emarginate stigmas, and raised on a slender stalk three or four times as long as 
the scale. The capsule is elongated, long-stalked, light brown slightly tinged with red, and about a 
quarter of an inch in length. 
Salix cordata, var. Mackenzieana, which is still very little known, is distributed from the shores 
of Great Slave Lake southward through the region at the eastern base of the Rocky Mountains to 
northern Idaho and to Lake County, California, and is now usually regarded as a western form of the ~ 
shrubby Salix cordata,' one of the commonest and most variable Willows of North America, ranging 
1 Muehlenberg, Neue Schrift. Gesell. Nat. Fr. Berlin, iv. 236, t. 
6, f. 3 (1803); Konig & Sims Ann. Bot. ii. 64, t. 5, £. 3. — Michaux, 
Fl. Bor.-Am. ii. 225. — Willdenow, Spec. iv. pt. ii. 666. — Persoon, 
Syn. ii. 599.— Pursh, Fl. Am. Sept. ii. 615.— Nuttall, Gen. ii. 
231. — Forbes, Salict. Woburn. 277. — Trautvetter, Mém. Sav. Etr. 
Acad. Sci. St. Pétersbourg, iii. 623. — Hooker, Fl. Bor.-Am. ii. 149. — 
Barratt, Sal. Amer. No. 26.— Torrey, Fl. N. Y. ii. 211.— Emer- 
son, Trees Mass. 275 ; ed. 2, i. 299, t. — Andersson, Ofvers. Vetensk. 
Akad. Férhandl. xv. 124 (Bidr. Nordam. Pilarter); Proc. Am. 
Acad. iv. 64; Svensk. Vetensk. Akad. Handl. ser. 4, v. 157 (Mo- 
nographia Salicum) ; De Candolle Prodr. xvi. pt. ii. 251.— Ward, 
Bull. U. S. Nat. Mus. No. 22, 116 (Fl. Washington). — Bebb, 
