180 SILVA OF NORTH AMERICA. SALICACE. 
A tree, sometimes a hundred feet in height, with a trunk occasionally seven or eight feet in 
diameter, divided often twenty or thirty feet above the ground into several massive limbs which spread 
gradually and, becoming pendulous toward their extremities, form a graceful rather open head frequently 
a hundred feet across, or on young trees are nearly erect above and, spreading below almost at right 
angles with the stem, form a symmetrical pyramidal head. The bark on the trunk is from an inch and 
a half to two inches in thickness, ashy gray, and deeply divided into broad rounded ridges broken into 
closely appressed. scales which cover the light yellow inner bark ; on young stems and branches it is 
thin, smooth, and light yellow tinged with green. The branchlets are stout and marked with long pale 
lenticels, and are terete or, especially on vigorous young trees, become angled usually in their second 
year, with thin pale more or less prominent wings extending downward from the two sides and the 
bases of the large three-lobed leaf-scars which are truncate or slightly emarginate above. The buds 
are resinous, ovate, acute, the lateral much flattened by pressure against the branch, half an inch long, 
and covered by six or seven light chestnut-brown lustrous scales slightly puberulous toward the base of 
the bud. The leaves are deltoid or broadly ovate, usually abruptly or gradually acuminate with long 
slender entire points or rarely rounded at the apex, truncate, slightly cordate or occasionally abruptly 
wedge-shaped at the base, which is generally entire, and coarsely crenately serrate with incurved 
glandular teeth; when they unfold they are gummy, fragrant with a balsamic odor, covered more 
thickly below than above with soft white caducous hairs, and furnished on the margin with a short 
dense fringe of white deciduous tomentum ; and at maturity they are thick and firm in texture, light 
bright green and lustrous, paler on the lower than on the upper surface, and from three to five inches 
in length and breadth, with stout yellow midribs often tinged with red toward the base and raised and 
rounded on the upper side, from five to seven pairs of conspicuous primary veins which spread nearly 
at right angles with a slight upward curve and are forked at some distance from the margins, slender 
connecting cross-veins, and rather obscure reticulate veinlets ; they are borne on slender petioles pilose 
at first but soon glabrous, compressed laterally, yellow more or less tinged with red, and from two and 
a half to three and a half inches in length, and flutter with the lightest breeze; in the autumn they 
turn clear bright yellow before falling. The stipules of the first leaves are strap-shaped, acute, slightly 
concave, yellow-green, an inch long, about an eighth of an inch wide, and caducous; those higher on 
the branch are linear-lanceolate, white and scarious, and often less than half an inch in length. The 
flower-buds are broadly ovate, obtuse, nearly half an inch long, and covered by about five scales which 
disappear before the flowers expand. The aments hang on short peduncles and develop before the 
appearance of the leaves ; those of the staminate tree are densely flowered, from three to four inches in 
length and half an inch in thickness, with stout glabrous stems, and those of the pistillate tree are 
sparsely flowered and thin-stemmed, and often become a foot long before the ripening of the capsules, 
which are raised on slender stems from one third to one half of an inch in length; the scales are 
scarious, light brown and glabrous, dilated and irregularly divided at the apex into filiform lobes, and 
caducous. The stamens are composed of short filaments and large dark red anthers, and are inserted 
to the number of sixty or more on a broad oblique disk with slightly thickened revolute margins. 
The ovary is subglobose, crowned by three or four nearly sessile dilated or laciniately lobed stigmas, 
and surrounded at the base by a broad cup-shaped membranaceous disk persistent under the fruit. 
The capsule is oblong-ovate, rather abruptly contracted and acute at the apex, slightly pitted, thin- 
walled, from one quarter to one half of an inch long, dark green, and three or four-valved. The 
seed is oblong-obovate, rounded at the apex, light brown, about a twelfth of an inch in length, and 
surrounded by a tuft of long white or slightly rusty colored hairs which inclose the mature ament 
in the mass of soft delicate cotton that has given to this tree its common name. 
Populus deltoidea inhabits the banks of streams, where it often forms extensive open groves, and 
is distributed from the valley of the lower Maurice River in the province of Quebec! and the shores of 
? Provancher, Flore Canadienne, ii. 533.— Brunet, Cat. Vég. Lig. Can. 55.— Bell, Rep. Geolog. Surv. Can. 1879-80, 56°.— Macoun, 
Cat. Can. Pl. 457. 
