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THE IMPORTANCE OF DENSITY IN SYLVICULTURE. 
II. The Importance of Density in Sylviculture.’ By Dr Apam 
Scuwappacu, Professor of Forestry, Eberswalde, Prussia, 
Forestry may be defined as the management of woods upon a 
definite system, which shall secure continuity in the treatment 
and in the returns. Leaving woods that are planted for beauty 
or for protection against storms, etc., out of account, the owner 
endeavours to obtain the maximum of profit consistent with the 
uninterrupted maintenance of the yield—‘‘ maximum of profit” 
being synonymous with the maximum difference between the 
cost of production and gross revenue. This goal is reached by 
the observance of a number of guiding principles, cultural and 
otherwise, of which I sha]l here confine myself to the discussion 
of but one, namely, the influence of density, or number of trees 
per acre. As will be seen later on, this question has an intimate 
bearing upon the result of investigations into the influence of 
different degrees of thinning and light-felling. 
Other things being equal, the production of timber by individual 
trees stands in direct proportion to the physiological activity of 
their roots and leaves. The more extensive the roots, the better 
developed the crown, and the more perfect the proportion between 
both, so much the more completely is the tree enabled to utilise 
the nutritive substances in the soil and in the atmosphere, and, 
consequently, the greater will be the quantity of material which 
it will produce in a given time under the influence of light and 
heat. The best proof is found in the fact that, whereas a tree 
occupying an open situation in a park may produce rings an inch 
or more in breadth, a tree of the same species growing in a dense 
wood will show rings whose breadth is a mere fraction of this. 
On any given area we shall, therefore, obtain the maximum yield 
of timber if the density is so regulated that for any given age the 
number of trees is such as to admit of the perfect development 
of the crown and roots of each. On various occasions this view 
found expression in works on forestry early in the present century, 
as, for instance, in the writings of Cotta, and still more so in those 
of Liebich, a lecturer in the Polytechnic at Prague. 
The aim and object of forestry, however, consists not in the 
production of the greatest mass of wood, but in the production 
of the greatest revenue from a given area. Apart from cases that 
1 Read at a General Meeting held on 3rd August 1896. 
