614 AMERICAN FORESTRY 



ness but is so exacting in its soil and moisture requirements tliat only young 

 specimens should be used and its planting restricted to suburban sections. 



The ohjectionahle trees for street planting are all the poplars, the silver 

 and sycamore maples, the catalpa and male ailanthus. The poplars are very 

 short-lived trees. They are dangerous in windstorms and grow so fast as to 

 require constant cutting back. At a certain age their roots ui)set the sidewalk 

 and their fine rootlets clog the neighboring water and sewer pipes. Their 

 leaves drop very early in the fall and if the species is of the pistillate kind, the 

 catkins falling on the sidewalk become a danger and a nuisance to pedestrians. 

 The silver maples are constantly full of dead wood, are subject to boring insects 

 and are short-lived. The sycamore maple is a favorite of boring insects in the 

 vicinity of New York though in other places it has escaped these pests. The 

 variety of ailanthus tree that bears the male or staminate flowers generates a 

 strong, rather oppressive odor, but if the pistillate form is chosen, the tree will 

 produce a beautiful head and will grow in places where no other tree will 

 grow. 



Such are the principal problems of those charged with the care of street 

 trees. I have not attempted to dilate on the details of the work because they 

 are too numerous and because, as in every thing else, their solution will often 

 depend more upon the judgment of the forester in charge and upon the local 

 conditions than upon any rules that may be laid down. But whatever the 

 problems do not let us forget that they can always best be solved by one 

 equipped with technical knowledge and experience and that the trees are 

 worth the effort since they are always valued by the citizen and ultimately 

 lead to a better appreciation of the parks themselves. 



