BETULACEZ, SILVA OF NORTH AMERICA. 61 
BETULA NIGRA. 
Red Birch. River Birch. 
STROBILES cylindrical, oblong, erect. Leaves rhombic-ovate, acute at both ends, 
lustrous on the upper surface, pale and pubescent on the lower. 
Betula nigra, Linneus, Spec. 982 (1753). — Muenchhausen, Rep. Geolog. Surv. N. Car. 1860, iii. 73. — Regel, Nouv. 
Hausv. vy. 113. — Marshall, Arbust. Am. 18.— Schoepf, 
Mat. Med. Amer. 134. — Walter, Fl. Car. 231. — Wang- 
enheim, Beschreib. Nordam. Holz. 92. — Castiglioni, Viag. 
negli Statt Uniti, ii. 207. —Gertner, Fruct. ii. 54, t. 
90. — Willdenow, Berl. Baumz. 42; Spec. iv. pt. i. 
464; Enum. 981. — Borkhausen, Handb. Forstbot. i. 
505. — Nouveau Duhamel, iii. 203, t. 51. — Persoon, Syn. 
ii. 572. — Desfontaines, Hist. Arb. ii. 477. — Du Mont 
de Courset, Bot. Cult. ed. 2, vi. 408. — Stokes, Bot. Mat. 
Med. iv. 368. — Pursh, Fl. Am. Sept. ii. 621. — Nuttall, 
Gen. ii. 218. — Hayne, Dendr. Fl. 166. — Poiret, Lam. 
Dict. Ill. iii. 350, t. 760, £. 2. — Elliott, Sk. ii. 616. — 
Jaume St. Hilaire, Traité des Arbres Forestiers, t. 8. — 
Watson, Dendr. Brit. ii. 153, t. 153. — Sprengel, Syst. iii. 
854. — Torrey, Fl. N. Y. ii. 201. — Emerson, Trees Mass. 
208; ed. 2, i. 237. — Darlington, FU. Cestr. ed. 3, 275. — - 
Mém. Soc. Nat. Mose. xiii. 118, t. 12, f. 1-12, t. 13, 
f. 30-37 (Monographia Betulacearum) ; Bull. Soc. Nat. 
Mose. xxxviii. pt. ii. 412 (Gattungen Betula und Alnus) ; 
De Candolle Prodr. xvi. pt. ii. 175. — K. Koch, Dendr. ii. 
pt. i. 644. — Lauche, Deutsche Dendr. ed. 2, 273. — Bur- 
bank, Proc. Bost. Soc. Nat. Hist. 1882, 85. — Sargent, 
Forest Trees N. Am. 10th Census U. S. ix. 161. — Wat- 
son & Coulter, Gray’s Man. ed. 6, 472.— Dippel, Handb. 
Laubholzk. ii. 186.— Koehne, Deutsche Dendr. 107.— 
Coulter, Contrib. U. S. Nat. Herb. ii. 413 (Man. Pl. W. 
Texas). 
Betula lanulosa, Michaux, Fl. Bor.-Am. ii. 181 (1803). — 
Nouveau Duhamel, iii. 206. 
Betula rubra, Michaux f. Hist. Arb. Am. ii. 142, t. 3 
(1812). — Loddiges, Bot. Cab. xiii. t. 1248. — Spach, 
Ann. Sci. Nat. sér. 2, xv. 185 (Revisio Betulacearum) ; 
Dietrich, Syn. v. 303. — Chapman, Fl. 428. — Curtis Hist. Vég. xi. 230.— Endlicher, Gen. Suppl. iv. pt. ii. 19. 
A tree, eighty or ninety feet in height, with a trunk which often divides, fifteen or twenty feet 
above the ground, into two or three slightly diverging limbs and is sometimes five feet in diameter, and 
stout spreading comparatively slender pendulous branches forming, while the tree is young, an open 
pyramidal head, and in old age a narrow round-topped very irregular and picturesque crown ; or often 
the Red Birch sends up from the ground a clump of several small spreading stems forming a low 
bushy tree. The bark at the base of old trunks is from three quarters of an inch to an inch in 
thickness, dark red-brown, deeply furrowed, and broken on the surface into thick closely appressed 
scales ; higher on the trunk, on the large branches, and on young stems, it is much thinner, lustrous, 
light reddish brown or silvery gray and marked with narrow slightly darker longitudinal lenticels, and 
separates freely into thin papery plates which remain for several years on the stem and branches, curling 
back and showing the light pink-brown tints of the freshly exposed inner layers of bark. The branchlets 
are slender and at first are coated with thick pale or slightly rufous tomentum which gradually disap- 
pears before the winter, when they become dark red and lustrous, and are marked with minute pale 
lenticels; in their second season they are dull red-brown and then grow slightly darker during several 
years, until the bark begins to separate into the thin flakes which cover the older branches. The buds 
are ovate, acute, and about a quarter of an inch long ; in summer, when they are fully grown, they are 
clothed with thick pale tomentum, and in the winter are glabrous or slightly puberulous, lustrous, and 
bright chestnut-brown ; the inner scales, which are sometimes three quarters of an inch in length after 
the opening of the bud, are strap-shaped, light brown tinged with red, and coated with pale hairs. The 
leaves are rhombic-ovate, acute, abruptly or gradually narrowed and wedge-shaped at the base, and 
doubly serrate with small callous-tipped triangular teeth, or on vigorous young branches often more or 
less laciniately cut into acute doubly serrate lobes; when they unfold they are light yellow-green and 
