8 BULLETIN 205. 



northern winters uninjured and develops rapidly into a splendid and shapely 

 tree large enough for the widest avenues or capable of being adapted by 

 pruning, to which it most readily submits, to very narrow streets. Such is 

 the activity of its young wood and bark that the stem is at times completely 

 girdled without appreciable injury, and the outer layers of its cortex are 

 annually sloughed off during late summer and autumn, leaving the new 

 layers beneath entirely free from soot and dirt accumulated during the 

 summer. It is partly due to this, perhaps, that it enjoys with the ailan- 

 thus the distinction of being best adapted to parts of cities where smoke 

 and dust abound. 



The only serious enemy of the sycamore is a fungus which attacks its 

 shoots and young leaves in early summer, greatly disfiguring the tree. In 

 some cities of southern Europe complaint is made of the thick hairy cover- 

 ing which becomes detached from the young leaves and twigs and gets into 

 the nose and mouth producing an inflammation known as the "sycamore 

 cough." This tree is, however, most widely and abundantly employed in 

 the cities of India, Persia, and Europe, while in America it is deservedly 

 growing more popular as a street tree every year. In London, it is con- 

 sidered by many to be the only tree that will thrive in the dirt and smoke 

 of so large a city. 



Of the two common species of sycamore, the eastern is smaller and of 

 closer growth than our native species, though less hardy and less beautiful 

 in form. It was for some time thought, also, that the eastern species was 

 less subject to attack by the sycamore fungus, but this is probably not the 

 case. In this country, the oriental sycamore is usually preferred, while in 

 Paris the western species is used exclusively, since it seems to conform 

 better to the style of pruning adopted in that city. 



AILANTHUS. 



The ailanthus is another importation from the orient, less common than 

 the oriental sycamore, and, on account of some especially objectionable 

 qualities, very unpopular withithe public. Some of these qualities, however, 

 are not serious faults and may be entirely corrected with proper care. For 

 example, the unpleasant odor at blossoming time is confined to the male 

 flowers, and trees bearing these flowers need not be cultivated. The habit 

 of sprouting profusely at the roots, though dangerous to pavements, ren- 

 ders the propagation of the ailanthus extremely easy, and also make it pos- 

 sible to select only the desirable trees. Those who object to the odor of the 

 male flowers for two or three days, however, must endure the sight of the 

 ugly brown fruit -clusters which often hang upon the tree throughout the 

 winter. A fault which cannot be remedied is the early maturity and disfig- 

 urement accompanying rapid growth. When young, the ailanthus is vig- 

 orous and shapely, if property trained, and its large leaves are green until 

 frost, but most of the old trees I have seen, present a very scraggly and 

 unsightly appearance. There are fine avenues of this tree in Paris, where it 



