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Providence ordained the vegetable products of the earth, for certain 
natural purposes, and in their natural unmolested growth, the root, the 
trunk, the leaves and the fruit are in the proportions precisely adapted to 
the purposes of nature. For example, take any forest trees and crowd 
them together in a thick grove, the necessity of their reproduction will 
be but little felt, because the ground upon which they stand is already bur- 
thened and taxed to its capacity to supply nourishment for their growth, 
and the consequence is that the fruit and seed—their means of reproduc¬ 
tion—are produced in small proportion to the other parts of the trees. 
Thin out those trees, nature feels the loss, and makes an effort to restore it 
by the production of an increased proportion of fruit and seed that the per¬ 
petuation of the species may be insured beyond peradventure. It is by 
taking advantage of this law of nature that we are enabled so to alter the 
proportion in the growth of different parts of our trees as to give us a 
preponderance of any part we may desire. This year we wish a large 
growth of wood. We so manage the law as to acquire it. In a year or 
two more we feel that the tree should render us some return for our nur¬ 
ture and our care. The same law governs, and by its proper application 
we produce fruit at the expense of the wood. But to accomplish this it 
is necessary to know, first, the materials of which the wood and the fruit 
are severally formed ; and secondly, how to furnish to the tree the arti¬ 
cles of nourishment which form wood and those which form fruit, at our 
option. And this brings us to a consideration of the constituent parts of 
vegetables—in plain language, the materials of which they are formed. 
All vegetables are formed chiefly of four simple elements, or substances, 
viz.: oxygen, hydrogen, nitrogen, and carbon. Chemists call these the 
** organic” elements of vegetables. They constitute from 92 to 98 per 
cent, or nearly the whole of every vegetable substance—combined in 
a certain proportion, they form wood—in another proportion, fruit. The 
remaining 2 to 8 per cent, of vegetable matter is made up of certain sub¬ 
stances which chemists call the “inorganic” elements of vegetables. But 
I will not take time to discuss these here, as chance will pretty generally 
supply them to the trees in Wisconsin soils, at least all of them except 
potash, which can be supplied by frequent washing with soap suds, and 
■occasional manuring with leached ashes. Nor will I stop to describe the 
four simple, or organic elements above named, as a knowledge of the 
sources from which vegetables derive them, is sufficient for the purposes 
