THE POPLARS. 



The poplars, generically known as Popuhis, are large fast- 

 growing trees which are represented in Canada by several species, 

 commonly occurring. The balsam and the aspen poplar are us- 

 ually the most common, and are found in nearly all parts of the 

 Dominion, the aspen especially springing up after fires. Besides 

 their quick growth, a reason for their rapid spread is the nature 

 of the seed envelope, which is of light cottony texture, and by 

 which the seeds are carried for long distances on the wind. This 

 habit has made these trees objectionable for street purposes, as 

 when the seeds are falling the roads are covered with the white 

 cotton. The habit of spreading by suckers, which is specia^lly 

 noticeable in the balsam poplar, also causes them to be looked on 

 with disfavour. The poplars are subject to insect attack, and 

 the wood is soft and easily broken, so that they have but fenv ad- 

 vantages to commend them for omamntal purposes, the chief 

 one being their fast growth. 



The poplars are found in temperate or northern regions, but 

 range as far south as Nortliiem Mexico and Lower California. 

 There are nine species in North America, but their main habitat 

 is toward the north. The poplar is the oldest type of dicotvde- 

 donous plants yet identified, being common in North America 

 in the cretaceous period. 



Perhaps the best known species generally in Canada is the 

 Aspen Poplar {Populus trcwuloides) . known in the west as the 

 white poplar. It springs up everywhere, especially after fires, and 

 with its white trunk and light green shimmering foliage forms a 

 beautiful contrast to the dark coniferous trees amongst which it 

 grows. The trembling of the leaves is one of the most noticeable 

 characteristics of this tree, and has given it its specific name. The 

 peculiar movement of the leaves is occasioned by the fact that 

 the petioles or leaf stems are flattened laterally, and as a result 

 the slightest motion of the air causes them to tremble violently. 

 As this is more or less characteristic of the poplars it may have 



