(101) 



May, followed by the fruits about a month later, when the 

 stalk of the catkin becomes greatly elongated. 



The American aspen is a rapid grower, and consequently 

 the wood is soft and of little commercial importance, except 

 as a source of paper pulp. Tannin is extracted from the 

 bark. It grows best on moist gravelly soil or hillsides in the 

 area, but it is found quite generally throughout the northern 

 part of the continent. It is common along the upper 

 Hudson, and extends southward to Staten Island. 



Large-toothed Aspen Populus grandidentata 



The tree may be distinguished from the common aspen by 

 its leaves which are broader than in the latter. The teeth 

 on the margin of the leaf-blade are at least twice as large 

 as those on the aspen, and they are not incurved. The buds 

 of the aspen are usually quite smooth but in the large-toothed 

 aspen they are uniformly clothed with dense hairs. 



This tree prefers moist soil near swamps or streams, and it 

 is confined to the eastern part of Canada and the United 

 States. It is known to grow throughout the Hudson 

 Valley. 



Black Willow Salix nigra 



Most of the willows of the Hudson Valley are mere 

 shrubs, but the black willow is a tree 30 to 40 feet high. 

 There are a few more that very rarely become trees, 

 although their characteristic habit is shrub-like. The bark 

 of the black willow is dark brown or nearly black, but some- 

 times it is lighter brown tinged with orange. The branches 

 are stout and spreading, giving the tree an open irregular 

 head. 



The leaves, which are alternately arranged on the reddish 

 twigs, have lance-shaped blades from 3 to 6 inches long and 

 are finely toothed on the margin. In age the leaf-blades 

 may become scythe-shaped. 



The flowers are clustered to form the well-known catkin. 

 In the black willow they are found on short twigs, and bloom 

 with the appearance of the leaves in early spring. 



