Naturalisation in Extra- Tropical Countries. ^79 



Fopulus Fremontii, S. Watson. 



California and adjoining States, on river-banks. Tree, attaining 

 about 150 feet in height and 4| feet in stem-diameter ; leaves large. 

 Mnch landed for shading road-sides and promenades, for which 

 however the staminate trees should only be selected. Wood less 

 white than that of P. tremuloides, excellent for dry goods, fruit- 

 butter- and salt-boxes, trays, bowls and other articles ; outer bark 

 a fair substitute for cork. The foliage brightens splendidly in 

 autumn. Wood convertible into paper-pulp. [Dr. Kellogg]. 



Fopulus grandidentata. Michaux. 



The Soft Aspen. Eastern North-America. To 80 feet high. 

 Wood whitish, soft, very light ; can be ground into pulp for paper. 

 The oldest name seems P. deltoides, Marsh. 



Populus heterophylla, Linne. 



The Downy Poplar of North- America, passing also by the name 

 of Cottonwood. Height often 60 feet. The wood is very pale, soft 

 and fissile. All poplars, like willows, are very important to eliminate 

 miasma by absorbing humidity to an enormous extent from stagnant 

 swampy localities ; they are likewise good scavengers of back-yards. 



Populus nigra, C. Bauhin. 



The European Black Poplar, extending spontaneously to China ; 

 in the Himalayas up to 12,500 feet. With P. Canadensis and P. 

 balsamifera very fitted for smoky places in manufacturing towns 

 [J. Udale] ; the spreading variety is one of the best of trees for 

 lining roads. This species includes P. dilatata (Aiton), and as a 

 contracted variety P. fastigiata (Desfontaines), the Lombardy- 

 Poplar. Among trees the latter is one of the most eligible to plant 

 near houses for serving as a lightning conductor. Greatest height 

 150 feet. Growth rapid, like that of all other poplars, or even 

 more so. At Bensberg a Black Poplar formed in 80 years a stem 

 19 feet in circumference ; at Wippach a hollow stem showed a 

 girth of 48 feet. In warm zones the growth is still more rapid 

 than in Middle Europe, as is the case with the majority of trees. 

 Northward hardy to Christiania. Wood soft, light and of loose 

 texture, used for joiners', coopers' and turners' work ; also for 

 matches ; in Upper India for light boxes to serve in the transit of 

 fruits ; furnishing furthermore superior charcoal for gunpowder. 

 Bark employed in tanning, producing a fragrant leather; it is 

 however not rich in tannic acid. The tree requires damp soil. It 

 retains its foliage longer than most poplars through the season. 

 Already Hippocrates used it medicinally. 



Fopulus tremula. C. Bauhin. 



The Aspen. Europe, North-Africa, Northern Asia to Japan. 

 Height reaching to about 100 feet, stem-circumference to about 12 

 feet ; age 200 years or more. Emits suckers ; content with sandy 



