Division Spermatophyta 



Subdivision Angiospermae 

 Class Dicotyledoneae 

 Order Sapindales 



Family Aceraceae 

 Genus Acer 



Species saccharum 

 Variety nigrum. 



HABIT. Habit, or the general appearance of a plant, is 

 an important character of identification, especially as we become 

 more and more familiar with the trees. Two main types are 

 recognized, based on the manner of branching of the trunk, the 

 upright and the spreading. In the one the trunk extends straight 

 upwards without dividing, as is typical in most of the conifers, 

 and in the other the trunk divides to form several large brandies 

 and the broad, spreading crown of most of our broad-leaf trees. 

 The crown in either case may be regular in outline or very 

 irregular, straggling or straight-limbed. Moreover, the tree 

 growing in the open, where there is no crowding and there is 

 plenty of light, may differ very greatly from the tree in the 

 forest, where the struggle for existence becomes very keen. A 

 short, thick trunk and low, spreading, many-branched crown 

 characterizes the tree in the open, whereas the forest tree 'has a 

 long, slender, clean trunk and a narrow crown of few branches. 

 In the descriptions of trees in this bulletin, unless otherwise 

 stated, the habit in the open is the one given. Again, the tree 

 may have been injured by storm or insect at some period of its 

 growth and its natural symmetry destroyed. Moreover, the age 

 of a tree has a great influence on its outline, young trees being 

 generally narrow and more or less conical, broadening out as 

 they become older. We may say, then, that each tree has an indi- 

 viduality of its own, little eccentricities similar to those that make 

 people different from each other. And just as we have little 

 difficulty in recognizing our friends at a distance by some peculiar- 

 ity of walk or action, so are we able to recognize a great many 

 trees at a distance by some peculiarity of form or habit. 



LEAVES. With the advent of spring the -buds of our broad- 

 leaf trees swell and burst and the leaves come forth and clothe 

 the trees with mantles of green, hiding the branches which lhave 

 been bare through the cold winter months. The evergreens, too, 



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