200 



BETULACEiE. 



Betula. 



3. Betula lenta, Linn. (Plate CXIII.) Cherry Birch. Black Birch. 



Leaves cordate-ovate, acuminate, sharply serrate , the nerves underneath and the petioles 

 hairy ; fertile aments elliptical -ovoid, erect, or with the short peduncles recurved ; bracts 

 roughly pubescent , the lobes nearly equal, rather obtuse, diverging, prominently veined. — 

 Linn. sp. (ed. 2.) 2. p. 1394 ; Michx. sylv. 1. t. 74 ; Pursh, fl. 2. p. 621 ; Ell. sk. 2. p. 617 ; 

 Bigel. fl. Bost. p. 356 ; Torr. compend. p. 356 ; Beck, hot. p. 325 ; Darlingt. fl. Cest. 

 p. 540; Hook. fl. Bor.-Am. 2. p. 156. B. carpinifolia, " Ehrh. beitr. 6. p. 99;" Michx. 

 fl. 2. p. 181. 



A tree 30 - 60 feet high and 1-2 feet in diameter, with numerous slender branches, which 

 are of a dark chestnut-brown and speckled with white scars : cuticle of the bark smooth, 

 grayish, and resembling that of the common cherry-tree. Leaves 2-3 inches long, more or 

 less cordate at the base ; when young, clothed with silky hairs, but finally smooth, except on 

 the veins underneath and the petiole. Sterile aments 3-4 inches long, pendulous, terminal. 

 Fertile aments (when in fruit) about an inch long, and half an inch or more in diameter ; the 

 peduncle 1-3 lines long, usually erect, but sometimes a little curved, so that the ament is 

 horizontal. Bracts deeply 3-cleft, cuneate at the base. Nut elliptical, with a broad mem- 

 branaceous margin which is somewhat fringed towards the summit. 



In moist rich soils, throughout the State, except in the western counties, where it is rare. 

 Fl. April. Fr. August. A very useful tree. The wood is of a reddish tint, close-grained 

 and susceptible of a fine polish, so that it is much used for cabinet work. The young twigs 

 give out a pleasant aromatic odor when bruised, on which account this species is often called 

 Sweet Birch. 



4. Betula excelsa, Ait. Yellow Birch. 



Leaves ovate, acute, serrate, smooth on both sides , the petiole pubescent ; fertile aments 

 ovoid-oblong, erect, on short peduncles ; lobes of the bracts somewhat equal, acute, slightly 

 diverging. — Ait. Kew. (ed. 1.) 3. p. 337 ; Pursh, fl. 2. p. 261 ; " Duham. arb. 3. p. 203. 

 t. 52 ;" Bigel. fl. Bost. p. 356 ; Torr. compend. p. 355 ; Beck, bot. p. 325. B. lutea, 

 Michx. sylv. 1. t. 73. 



A tree 40 - 60 feet high and 1-2 feet in diameter. The epidermis is of a yellow color, 

 and separates in narrow transverse ribbons which roll outwards at the ends. Leaves about 

 3 inches long, downy when young, but smooth (except the petiole) when fully grown. Fertile 

 aments about an inch long and half an inch in diameter ; the short peduncle sometimes bent 

 at a right angle to the branch. 



Woods and swamps in the northern and western parts of the State ; common. Fl. April. 

 Fr. August. The young twigs and bark are sweet-scented, but less so than in the preceding 

 species. The wood is inferior in quality to that of the Black Birch, but is nevertheless much 

 employed for cabinet work. Much of the firewood used in Boston is of the Yellow Birch ; 

 and the bark is excellent for tanning. 



