Esthetic Forestry 193 
permanency of our composition. We can make sure, for 
example, that the tolerant and persistent growers, such as 
the beech, the sugar maple, the holly, the hemlock, the firs 
and spruces, will be able to hold their own in the struggle 
for light and air-space; while such extremely light-needing 
and not persistent growers as the aspen, white birch, black 
locust, soft maple, will soon be crowded out; finally the light- 
needing and yet persistent growers, like the Tulip tree, the 
oaks, the Yellow Birch, and the pines, if their heads are once 
above their neighbors, will be able to maintain themselves. 
With such knowledge we can formulate the general policy, 
namely, to reduce more or less rapidly the short-lived, light- 
needing species, which cannot maintain themselves in a mix- 
ture; and to keep the last-named species with their heads 
free and preferably in small groups, when the central ones 
at least will maintain themselves, those on the outside of the 
group succumbing gradually and being removed as dead 
wood. In this way these species have maintained them- 
selves in the natural forest, otherwise the shade-endurers 
would occupy all the ground, where not prevented by unsuit- 
able soil conditions. These latter alone will insure per- 
manency and should in most cases form the bulk of the 
woods, for in addition to permanency they also furnish the 
best protection to the soil by their shade and abundant leaf 
fall. 
There is one other feature influencing permanency which 
is often overlooked. Much of the woodland of hardwoods 
or deciduous trees which comes into park use is composed 
of coppice, 7.e., sprouts from the stump, the trees having 
been cut again and again and being replaced by stool shoots, 
not seedlings. Such stool shoots are of the nature of branches 
from the original bole, and do not grow in the same manner 
as do trees which grow from seedlings. Although develop- 
