CHAPTER IX 
THE STEM 
_ The Stem is that part of the plant axis which bears leaves or 
modifications of leaves and its branches are usually arranged with 
mathematical regularity. 
Stems usually grow toward the light and so are positively 
heliotropic. 
The principal functions of a stem are to bear and support 
leaves, branches and reproductive organs, connect roots with 
leaves, conduct water with minerals in solution from roots to 
leaves, to transport elaborated plant foods from the leaves to the 
roots and to store reserve foods. 
When the stem rises above ground and is apparent, the plant 
is said to be caulescent, as the various trees, shrubs, geraniums, etc. 
When no stem is visible, but only flower or leaf stalks, the 
plant is said to be acaulescent, as the Bloodroot and Violet. 
Stems vary in size from scarcely !¢5 inch in length, as in 
certain mosses, to a remarkable height of 400 feet or more. The 
giant Sequoia of California attains the height of 420 feet and has a 
trunk diameter at its base of between 25 and 30 feet. Some of 
the Eucalyptus trees of Australia and Tasmania are reported to 
attain the height of 500 feet. 
Nopes AND INTERNODES.—The nodes are the joints of stems. 
They represent the parts of the stem from which leaves or 
branches arise. Internodes are the parts of stems between nodes. 
Direction OF STEM GrowrH.—Generally the growth of the 
stem is upright or erect. Very frequently it may be: 
Ascending, or rising obliquely upward. Example: Saw 
Palmetto. 
Reclining, ox at first erect but afterward bending over and 
trailing upon the gound. Examples: Raspberry and Blackberry. 
Procumbent, lying wholly upon the ground. Example: 
Pipsissewa. 
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