234 



Bulletin 68. 



12. Populus alba (Linnaeus, Sp. PI. 1034 ( 1753)- White 

 Poplar, AbelE- A common European tree frequently planted 

 in this country. Leaves much like those oi Popiihis graiididen- 

 tata, but smaller, usually thicker and more angular, the under 

 surface — especially early in the season — woolly white. The 

 straight, strong cylindrical winter shoots of this species and its 



varieties, with the very 

 small buds, are shown at 

 o, n, and m, in fig. i. 



The typical form of 

 Populus alba is less 

 grown here than the var- 

 ieties with lobed and very 

 white-bottomed (and 

 occasionally variegated) 

 leaves. 



P. alba, var. nivea 

 (Wesmael, DC. Prodr. 

 xvi. 2d part, 324. P. nivea, 

 Willd. P. argentea of 

 nurserymen). This is 

 the commonest form of 

 white poplar in this coun- 

 try. It is known by the 

 snow-white under surfaces of its foliage and the three or five 

 lobed maple-like leaves. It is far too frequent about old yards, 

 where its inveterate brood of suckers make it a perpetual nuisance. 

 It is sometimes called Silver maple, from the resemblance of its 

 foliage to that of the maple. The tree is so obtrusive in its char- 

 acter that it can rarely be used with good effect in home 

 grounds. As a street tree in cities it is particularly offensive for 

 the cottony covering of the under side of the leaves and of the 

 shoots holds soot and dust, and it looks repulsively dirty. It is a 

 misfortune that the tree were ever brought into the country, for 

 few people appear to know how to make a considerate use of it. 



P. alba, var. canescens (Loudon, Encyc. 820). Fig. 16. 

 Leaves broad or nearly circular in general outline, prominently 

 notched but not lobed, the under surfaces and the young shoots 



16. Populus alba var. canescens ( 5^ nat. size) 



