48 MISSOURI BOTANICAL GARDEN BULLETIN 
symmetry and shade-giving habit, immunity to the attacks 
of fungi and insects causing disease, smoke and drought 
resistance, cleanliness of habit, and longevity. There is prac- 
tically no single kind of tree which will fulfill all of these 
requirements. 
The following tree species should receive consideration in 
St. Louis: : 
The sycamore is probably the best street tree for general 
planting, especially the oriental variety (Platanus orientalis 
intermedia). This tree has all of the vigor and hardiness 
of the American sycamore, but does not shed its leaves in 
the same abinolicabl way. It also has various qualities 
desirable in the street shade tree, which make it more ac- 
ceptable than most of the other species. It grows very 
rapidly, has a straight trunk, forms a round symmetrical 
head, is perfectly hardy, withstands the smoky atmosphere 
as well as any other species, and is comparatively free from — 
destructive diseases. At the same time, when properly 
pruned, it gives a very dense shade. 
Next to the sycamore the soft maple stands well in general 
estimation. Its rapid growth and the readiness with which 
it can be pruned to any desirable form have recommended 
it. The wood of this tree is very weak, however, and during 
severe wind storms, such as occur in the early part of the 
year, many of its branches are broken. It is, furthermore, 
very subject to the attack of various insect borers. 
The Carolina poplar has been planted on many streets, 
but is not a desirable tree except when used as a temporary 
filler, to be removed when the permanent trees, planted on 
either side, attain sufficient size. For streets located in the 
outer parts of the city, a more general planting of oaks can 
be recommended, especially the red or scarlet oak, both of 
which withstand considerable drought. Norway and sugar 
maples are also desirable. Tihe chief objection which can 
be offered to these trees is their slow growth, but where a 
ganar improvement is made, either of these trees will 
found superior to the soft maple. 
_ The tulip tree and white ash both do very well, except 
in the more congested districts, and both of them are ac- 
ceptable shade trees. Aside from the species enumerated, 
with the possible exception of one or two others, such as the 
, most other kinds will be found poorly adapted to 
the St. Louis climate and atmosphere. 
