49. SALlCACE.i^. 



139 



Ulmus campestris. 



an 



POPULIS 1 



hALIX 



The tree usually grown here is 

 var. s}(l>i'rosa, Loudon, with 

 corky wings on the branches 

 (Corkhiuked Elm). 



Cultivated for ornament and 

 often propagating itself by 

 suckers. — July - Sept. — Europe; 

 western Asia. 



Family 49.— SALIC AC E>E. 



Flowers dioecious, solitary in 



the axils of overlapping bracts, 



and forming spikes known as 



catkins; style 1; fruit capsular, 



small, 1-celled, opening from 



top to base in 2 valves ; seeds 



numerous, minute, with a tuft 



of long, silky hairs at base. 



Trees with soft, white wood 



and alternate, simple, decidu- 

 ous leaves. 



Catkins with jagged scales; perianth 



oblique cup; stamens 8-20 



Catkins with entire scales ; perianth repre- 

 sented by 12 glands; stamens 2-5 



1. POPULUS, L. 



Catkins finally drooping, cylindrical, appearing before 



the leaves, which are long-stalked. 



Leaves lobed or sinuate-toothed, the under- 

 side white-tomentose P. nlha 1 



Leaves finely and regularly toothed, the 



underside green and glabrous P. nigra 2 



1. Populus alba, L. 



FnpUtr. Tall tree, with 

 light-colored bark ; leaves 

 oval or almost circular, 

 lobed or sinuate - toothed, green 

 above, white-tomentose below, 

 the stalk flattened ; catkins with 

 jagged, hairy scales; stamens 8; 

 stigmas 4, in the shape of a cross. 



Grown for ornament and fre- 

 quently spreading by suckers. — 

 July - Aug. — Europe ; temperate 

 Asia. 



•2. P. nigra, L. Black Pop- 

 lar. Tall tree with sticky buds; 

 leaves almost triangular, acum- 

 inate, crenate-toothed, green on 

 both sides, the stalk flattened 

 at the summit ; catkin - scales 



White 

 smooth 



broad- 

 shortly 



