BETULACESA, 
SILVA OF NORTH AMERICA. 53 
BETULA LUTEA. 
Yellow Birch. Gray Birch. 
STROBILES oblong-ovoid, sessile, or short-stalked. 
cuneate, or slightly heart-shaped at the base. 
aromatic. 
Betula lutea, Michaux f. Hist. Arb. Am. ii. 152, t. 5 
(1812). — Spach, Ann. Sei. Nat. sér. 2, xv. 191 (Revisio 
Betulacearum) ; Hist. Vég. xi. 243. — Endlicher, Gen. 
Suppl. iv. pt. ii. 20. — K. Koch, Dendr. ii. pt. i. 640. — 
Sargent, Forest Trees N. Am. 10th Census U. S. ix. 
Leaves ovate, oblong-ovate, 
Bark yellow or silvery gray, slightly 
854. — Hooker, Fl. Bor.-Am. ii. 156. — Bigelow, Fl. Bos- 
ton. ed. 3, 382. — Torrey, FU. N. Y. ii. 200. — Gray, Man. 
422.— Emerson, Trees Mass. 206; ed. 2, i. 235, t. — 
Dietrich, Syn. v. 303.— Chapman, £7. 428. — Curtis, 
ep. Geolog. Surv. N. Car. 1860, iii. 74. 
161. — Lauche, Deutsche Dendr. ed. 2, 272. Watson & Betula lenta, a genuina, Regel, Nouv. Mém. Soc. Nat. 
Coulter, Gray's Man. ed. 6, 471. — Dippel, Handb. Laub- Mose. xiii. 125 (Monographia Betulacearum) (in part) 
holzk. ii. 184, £. 87. (1860). 
Betula excelsa, Pursh, Fl. Am. Sept. ii. 621 (not Aiton) Betula lenta, 8 lutea, Regel, De Candolle Prodr. xvi. pt. 
(1814). — Nuttall, Gen. ii. 218. — Sprengel, Syst. iii. i. 179 (1868). — Koehne, Deutsche Dendr. 107. 
A tree, occasionally one hundred feet high, with a trunk three or four feet in diameter; or, in the 
neighborhood of the coast and toward the southern and the extreme northwestern limits of its range, 
much smaller and often not more than twenty or thirty feet in height. The bark, which is aromatic 
and slightly bitter, is about half an inch thick on old trunks, reddish brown, and divided by narrow 
nregular fissures into large thin plates covered with minute closely appressed scales; on young trunks 
it is much thinner, bright silvery gray, or light orange-colored, very lustrous, and close and firm or 
somewhat divided, the edges of the irregular fissures breaking into thin layers; on the branches it is 
thin, separating freely into large persistent papery scales more or less rolled on the borders. The branches 
are long and usually comparatively slender, although large individuals often produce several stout limbs ; 
on young plants they grow at first perpendicularly or spread slightly, and form a broad-based pyramid ; 
but as some of the upper branches develop more vigorously than those near the ground, the tree 
begins to form the broad round-topped head of spreading and more or less pendulous branches which 
distinguishes it when it has reached its prime. When they first appear the branchlets are green and 
covered with long pale hairs, and during their first summer are light orange-brown and pilose; during 
their first winter they are glabrous, and light brown slightly tinged with orange or often flushed 
with red on the side exposed to the sun; in their second season they are dark orange-brown and 
lustrous, and then gradually grow darker and lose their lustre. The buds are about a quarter of an inch 
long, dull green, somewhat viscid, and covered with loose pale hairs during the summer ; and in winter 
they are light chestnut-brown, acute, and slightly puberulous. The leaves are ovate or oblong-ovate, 
acuminate or acute at the apex, gradually narrowed to the rounded cuneate or rarely heart-shaped 
usually oblique base, sharply doubly serrate with incurved or spreading gland-tipped teeth, and slightly 
aromatic ; as they unfold they are conspicuously plicate, bronze green or red, and pilose with long pale 
hairs on the upper surface and on the under side of the midribs and veins, and at maturity they are 
dark dull green above, yellow-green below, from three to four and a half inches long, and from an inch 
and a half to two inches wide, with stout midribs and numerous primary veins impressed above and 
covered below, especially near the base of the leaf and in the axils of the veins, with short pale or 
rufous hairs; they are borne on slender pale yellow hairy grooved petioles from three quarters of an 
inch to an inch in length, and turn to a clear bright yellow color in the autumn before falling. The 
