Betula 983 



wood, Haslemere, a tree planted in 1882, which was obtained from a nursery 

 at Newry, was 30 feet high and 2 feet i inch in girth in 1906, 



There are three trees about 20 feet high in the Botanic Garden of Trinity 

 College, Dublin, which, according to Burbidge,^ were raised from seed sent by 

 Sir Joseph Hooker in 188 1. At Castlewellan there are some young trees, about 

 8, feet high, which were obtained by grafting branches of the Dublin trees on the 

 common birch. (A, H.) 



BETULA PAPYRIFERA, Paper Birch, Canoe Birch 



Betula papyrifera, Marshall, Arbust. Am. 19 (1785); Sargent, Silva N. Amer. ix. 57, t. 451 (1896), 



and Trees N. Amer. 202 (1905)5 Winkler, Betulaceee, 83 (1904). 

 Betula lenta, Wangenheim, Nbrdam. Holz. 45 (1787) (not Linnaeus). 



Betula papyracea, Aiton, Hort. Kew. iii. 337 (1789); Loudon, Arb. et Frut. Brit. iii. 1708 (1838). 

 Betula grandis, Schrader, Ind. Hort. Bot. Goett. 2 (1833). 

 Betula latifolia, Tausch, in Flora, xxi. 2 p. 751 (1838). 



Betula alba, Linnaeus, yax. papyrifera, Spach, in Attn. Sc. Nat. ser. 2, xv. 188 (1841). 

 Betula cordifolia, Regel, Monog. Betulacece, 86 (1861). 

 Betula macrophylla, Hort., ex. Schneider, Laubholzkunde, i. 115 (1904). 



A tree, usually attaining in America, in its typical form, 60 or 70 feet in height 

 and 2 or 3 feet in diameter, the variety found on the lower Fraser River in British 

 Columbia being usually much larger in size. Bark thin, smooth, creamy-white, 

 marked with long, narrow, horizontal lenticels, and separating into thin papery 

 layers ; becoming on old trunks near the base \ inch thick, dull brown or blackish, 

 fissured, and scaly. Young branchlets, with scattered long hairs, mostly falling 

 off in summer ; in the second year dark brown and glabrous. 



Leaves (Plate 269, Fig. 5), 2 to 3 inches long, \\ to 2 inches wide, ovate ; rounded 

 or slightly cordate at the base, acuminate at the apex ; margin ciliate and irregularly 

 bi-serrate ; nerves six to eight pairs ; upper surface dull green, slightly pilose on the 

 nerves ; lower surface paler, with numerous minute brown glands, usually glabrous 

 except for dense axil-tufts of pubescence and a few long hairs on the midrib and 

 nerves, occasionally minutely pubescent between the nerves ; petiole at first pilose, 

 ultimately glabrescent. 



Fruiting catkins (Plate 269, Fig. 5), cylindrical, about \\ inch long, \ inch thick, 

 hanging on slender stalks ; scales pubescent or glabrous, ciliate, with the middle 

 lobe longer than broad ; lateral lobes rounded, erect, spreading or recurved. Nutlet 

 with broad wings. 



In winter the twigs usually show a few scattered long hairs ; buds, f inch long, 

 appressed to the branchlet, ovoid, acute, with glabrous, ciliate scales, glistening 

 with resin. 



Varieties and Hybrids 



This species, spread over a vast territory in North America, is very variable in 

 the wild state ; and the forms occurring on the Rocky Mountains and in the Pacific 



' Proc. Roy. Hort. Soc. 1 901, p. xxxviii. 



