SELECTION OF TREES FOR PLANTING 
43 
the grass, and produce undesirable dampness by inter¬ 
fering with speedy drying-out after rainfall. It may often 
be much better to have trees of more upright growth. 
If the upright trees lack the over-arching beauty of the 
others, they offer compensation in their individual state¬ 
liness, and by serving as a beautiful frame for setting off 
their environment. A thoroughfare lined with trees of 
this type offers a vista not possible with the trees which 
arch the roadway from curb to curb. A variation is the 
use of trees of a type to be kept closely pruned into small 
size and formal shape. For exclusive business streets and 
those where narrow sidewalks and poor growing conditions 
are a handicap, this is particularly desirable. It is much 
used in European cities, where careful attention has been 
given to tree planting. With proper attention and care, 
trees of small size will thrive in small patches of soil 
where larger trees, with their spreading root systems, 
might languish. The effect of these formally pruned trees 
is dignified and decorative, and gives a fine touch of green 
to a street lined with high-class shops or handsome houses 
in solid rows. An important advantage of this type of 
planting is that, in the event of the death of one of the 
trees, replacement is easy when nursery stock is kept for 
the purpose. European cities provide for replacements by 
keeping a supply of fair-sized trees in municipal nurseries 
for emergency use. Since all the trees are kept pruned to 
small size, little time is required before a transplanted tree 
has developed a crown uniform with that of the older tree. 
Clean habits are as important in trees as in human 
beings. Some trees are entirely lacking in observance of 
the proprieties as to causing litter through blooms or 
fruit or through the breaking and falling of fragile twigs 
and branches. These trees are to be avoided for the sake 
of neighborhood pride in good housekeeping. The Caro- 
