210 WOODY PLANTS OF MASSACHUSETTS. 



Sp. 4. The Canoe Birch. B. papyracea. Aiton. 



The leaves and strobile are figured in Michaux, Sylva, II, pi. 69 ; the tree, 

 leaves and aments in Loudon, Arboretum, VII, Plate 236. 



The paper birch is a northern tree, being found as far north 

 as latitude 65°. It grows naturally on river banks and in 

 moist, deep soil, flourishing in almost any situation, but never 

 attaining a very large size in Massachusetts. It is a picturesque 

 tree ; the points of light from its white trunk producing a bril- 

 liant effect in the midst of its soft but glittering foliage, hanging, 

 as we often see it, over some mountain stream, or sweeping up 

 with a graceful curve from the side of its steep bank. 



The recent shoots are of a reddish or purplish olive green, 

 gradually deepening, in successive years, into a dark copper 

 bronze, conspicuously dotted with grayish brown dots, and con- 

 trasting strikingly with the white trunk. The larger branches 

 and upper part of the trunk, and portions of the lower, have 

 often a red tinge, whence the tree has been sometimes mistaken 

 for the red birch, which is not found quite so far north. The 

 smooth white bark of the trunk may be easily separated into 

 thin horizontal layers, of an orange color within. The lenti- 

 cellar dots of the twigs become, on the larger trunks, horizontal 

 stripes of a yellowish brick or orange color, two or three inches 

 long, and a line wide. 



The leaves are alternate on the growing branches, and in 

 pairs below, on tapering footstalks, of one quarter or one third of 

 their length. They are from two to four inches long, and some- 

 times more than two wide, often inequilateral, broad, oblong- 

 egg-shaped, inclining to heater-shaped, tapering to a point, ir- 

 regularly, doubly and coarsely, but sharply serrate; smooth 

 above, roughly reticulated beneath ; dotted above and beneath, 

 when young, with resinous, silvery dots, and downy about the 

 axils of the veins beneath. They resemble the leaves of the 

 common gray birch, but are broader towards the extremity. 



The male flowers are in pendulous catkins, three or four 

 inches long, with the scales very slightly fringed. The fertile 

 catkins are longer than in the other birches, and have their 



