Betula 983 



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

 at Newry, was 30 feet high and 2 feet 1 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, 1 were raised from seed sent by 

 Sir Joseph Hooker in 1881. At Castlewellan there are some young trees, about 

 8 t 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 papyri/era, Marshall, Arbust. Am. 19 (1785); Sargent, Silva N. Amer. ix. 57, t. 451 (1896), 



and Trees N. Amer. 202 (1905); Winkler, Betulacece, 83 (1904). 

 Betula lenta, Wangenheim, Nordam. 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, var. papyri/era, Spach, in Ann. 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, 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 



1 Proc. Roy. Hort. Soc. 1 90 1, p. xxxviii. 



