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CHAPTER VII 
THE TREE—ITS ROOT-SYSTEM 
WE may now suppose the young oak-plant to be rapidly 
developing into a tree. ‘Technically the seedling is said 
to be a plant after the first year, and when it reaches 
the height of a few feet the young tree is called a sap- 
ling; these ideas are by no means well defined, however, 
and we may regard them as arbitrary terms of little or 
no scientific value. 
The principal changes which are noticeable as the 
little tree grows larger are the gradual increase in the 
length and thickness of the stem, and in the number 
and spread of the branches put forth year after year. 
Corresponding with these increments, each spring sees 
a greater number of leaves than the one before, and itis 
easy to prove that the roots also become more numerous 
and complex each season. 
The above simply expresses certain facts of observa- 
tion, but it is more accurate to link them together as 
follows. 
In each successive season of growth the young oak 
develops more leaves than it did before—in other words, 
