66 



TREES AS GOOD CITIZENS 



them is with branches resting on the ground, and the 

 removal of these destroys the beauty of the tree. More 

 over, they will not withstand the soot and dust and sul 

 phur fumes prevalent in a city. 



Hackberry. Because of its ability to thrive in 



poor soil and in varying cli 

 mates, the Hackberry has 

 staunch friends among the 

 planters of street shade 

 trees, especially in the south. 

 It is valuable in the western 

 half of the country, but in 

 the east it is rather ragged. 

 In appearance, it is much 

 like the Elm, although smal 

 ler and more erect. The tree 

 is affected in some places by a disease called Witches' Broom. 

 Ailanthus or Tree of Heaven. The chief recommen 

 dation for this tree for street planting is that it will 

 thrive where others would die. The poorest soil and 

 the most forbidding environment seem to offer no dis 

 couragement to it. Its growth is very rapid and, in its 

 younger years, it has attractive form, which it maintains 

 with advancing age if not 

 mutilated by accident or 

 severe pruning. It is useful 

 where other trees would not 

 grow, especially in the heart 

 of cities, and for this reason 

 should have its place among 

 trees to be considered for 

 congested areas. The foliage 

 is rich and heavy and prod 

 uces good shade. Because 



