176 



The Poplars 



12. BLACK POPLAR Populus nigra Linnaeus 



This European poplar has been found in the valleys of the Hudson and Dela- 

 ware rivers, doubtless spread from trees planted many years ago. The tree of the 

 Hudson valley was supposed by F. A. Michaux to be distinct from the European 

 black poplar, and was described by him under the name P. hudsonica. Little is 

 known of it in either valley at the present time. The Black poplar is widely dis- 

 tributed in Europe, becoming 30 meters high, with a trunk over one meter thick; 

 the branches spread widely and the tree is round-topped. 



Its bark is ashy gray, or that of old trunks darker, thick, rough, and furrowed. 



The young, round shoots and the leaves are 

 at first somewhat hairy, but become smooth 

 or nearly so, the twigs turning orange to 

 gray. The buds are ovoid, pointed, glutinous, 

 and about 8 mm. long. The leaves are 

 broadly triangular-ovate, firm in texture, 

 sharp-pointed, bluntly toothed, except near 

 the base and apex, 5 to 10 cm. long, the base 

 broadly wedge-shaped or truncate; they are 

 rather light green on both sides, the upper 

 surface shining; the leaf-stalks are flattened 

 sideways and are as long as the blades or 

 shorter. The catkins appear in March or 

 April, are hairy, and about 5 cm. long when 

 in flower, their scales long-fringed ; the stami- 

 nate ones are red. Bv the time that the 

 oblong, very blunt capsules have ripened, the 

 pistillate catkins have elongated to 10 or 12 cm., the stalks of the capsules re- 

 maining very short. The disk of the pistillate flowers is very small. 



The wood is yellowish, soft, and weak, with a specific gravity of about 0.45; 

 it is used in Europe for boxes and woodenware. The tree grows rapidly and 

 requires plenty of room for its full development. 



Fig. 133. Black Poplar. 



13. LOMBARDY POPLAR Populus italica Moench 



Populus dilatata Aiton 



While scarcely to be regarded as an element in the wild arborescent flora of 

 North America, the Lombardy poplar has been so much planted for ornament 

 and as a curiosity that it is as familiar in many places as any native species, and 

 it occasionally spreads by sending up shoots from its roots. It is widely distrib- 

 uted in Europe, but it is not definitely known to be native there, even in northern 

 Italy, and may have been introduced from Asia at a very remote period. The 

 tree is often regarded as a variety of the Black poplar, and it has been supposed 



