PARK AND CEMETERY . 
276 
in such planting, the failure of one or 
more trees in no way injures the de- 
sign, nor does the presence of small 
trees or younger trees growing to re- 
place older ones detract. Such informal- 
ity rather increases this picturesque type 
of beauty. 
It has been advocated by some experts 
that this informal planting should be 
applied to formal streets and avenues, 
but such treatment is absolutely contrary 
to the expression of a formal street 
or avenue, and cannot be seriously con- 
sidered in connection with good design. 
Among the suitable trees for boule- 
vard use in this climate are: the Ameri- 
can or English elm, the American and 
European beeches: Norway- and hard 
maples, locust, tulip, red, black, scarlet, 
pin and white oaks, hawthornes, white, 
river and black birches, etc. 
In addition to the regular park areas 
of a city, the reservations which are 
rapidly becoming a prominent part of 
our city park systems may be men- 
tioned here. In such reservations, tree 
preservation or production is the chief 
or only activity, and with the rapid pass- 
ing of our forests, these reservations 
seem to be the only places easily acces- 
sible to the bulk of our citizens, where 
an example of our .\merican forests, 
originally our heritage, may be preserved 
for our descendants. 
There are often areas in the vicinity 
of a city not at present containing ele- 
ments of woodland scenery which might 
be secured and by scientific forestry 
made to produce forest conditions. Such 
areas may be found in river fronts, 
swamps, barrens and stretches of aban- 
doned land where shrub growth has re- 
placed forest. Besides the park value 
of such woodland scenery and the pres- 
ervation of a small remnant of our for- 
ests for posterity, the utilitarian value 
of an annual tree crop, which scientific 
forestry could produce on such an area, 
is a consideration which the rapid 
diminution of our forests makes worth 
while. 
Fifth. Outlying Roads of Approach. 
Under this class we may group all our 
outlying city ways, both suburban and 
country roads, on those which in the 
course of time will in a reasonable prob- 
ability become resident portions, the 
planting should be such as for residen- 
tial streets, so that well established plan- 
tations of trees suitable to city condi- 
tions may be at hand when the home 
builders arrive. , 
For those roads, however, which are, 
and obviously will remain country roads 
to the end of the chapter, the planting 
should be suggested by that natural 
type commonly found along country 
roadsides. This is a picturesque group- 
ing of the trees with an undergrowth of 
shrubs and wild flowers. Roads treated 
in this manner may be made a valuable 
adjunct to the park system of a city. 
Where treeless roads are to be planted 
for the first time, immediate effects may 
be secured by using quick-growing trees 
as nurses, while slower-growing trees 
are maturing. Oaks are among the best 
for permanent trees on account of their 
hardihood, beauty and great age. Elms, 
maples, birches, beeches, pines and hem- 
locks may also be used. Elms need 
much greater attention than the others 
to hold their own against the attack of 
insects. 
Planting along these roads might also 
be done with utilitarian ends in view, as 
mentioned above, in connection with res- 
ervations. Two or more rows contain- 
ing trees of different ages, alternately 
planted, may be employed, the mature 
trees being removed for use, from time 
to time, and their places taken by the 
younger trees. 
spacing. These streets, none too wide 
even under proper condition's, at present 
with their two rows of crowded trees, 
give the general impression of conges- 
tion. In warm weather their solid lines 
of dense foliage prevent the free move- 
ment of the rather faint breezes and are 
really unhealthful. It would greatly im- 
prove such streets to have trees spaced 
at not less than fifty-foot intervals and 
alternately placed on the opposite sides 
of the street, as illustrated in the dia- 
grams eight and nine. 
Sometimes trees are planted closely 
for immediate effect, but this is a dan- 
gerous practice, as when the time ar- 
rives for thinning, public outcry against 
sacrificing the trees may very likely pre- 
vent its execution. An example of this 
occurred in Commonwealth Avenue, Bos- 
ton. Here four rows of English elms 
were planted by the elder Olmsted, as 
nurse trees to two rows of American 
elms. A few years ago, when the time 
was ripe for removing the English elms, 
public sentiment tied the hands of the 
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Trees, to be healthy and luxuriant, 
must grow as any other plant in good 
soil, and unless this is naturally very 
rich, the trees should be planted in good 
sized tree pits, from which the sand and 
gravel have been removed and replaced 
by good soil and fertilizer. 
The proper spacing of trees is equally 
as' important as proper planting, and the 
tendency is generally to plant much too 
closely. 
On very narrow streets the trees 
should be planted even farther apart 
than necessary for growth, in order to 
prevent excessive shutting out of light 
and air. 
The great majority of the east and 
west residential streets in Detroit are 
especially unfortunate in the matter of 
park commission, and today the six 
rows of trees remain, and are already 
causing serious crowding. 
The normal spacing of trees on 
streets of ordinary width depends on the 
variety of tree used. Elms and oaks 
should never be planted at less than 
thirty-foot intervals, while fifty feet is 
better. Maples, planes, etc., may be 
planted from thirty-five or forty feet 
apart, poplars not closer than ' twenty- 
five feet, and hornbeams and horse 
chestnuts twenty feet. 
In considering the various injuries to 
trees, Mr. Phillips shows by diagrams 
methods of prevention for some of the 
commonest tree troubles. 
If guy wires are attached directly to 
trees their pressure causes them to cut 
( Continued on p XII) 
