TRANSPLANTING. 
203 
from the upper portion of the plant, and deposited layer over 
layer at its extreme end ; these points or spongioles, as they are 
termed, are exceedingly delicate, are injured by very trifling 
causes, and, like all other recently formed vegetable matter, are 
extremely liygrometrical,—and thus having the power to absorb 
fluid or gaseous bodies, they are the main dependencies or 
feeding organs of the entire plant: this being their nature, we 
may readily conceive that they can only perform their office when 
in a moist medium, and experience shows that, with a few ex¬ 
ceptions, they will not otherwise exist. 
The connexion before mentioned as existing between the roots 
or lower portion, and the head or upper part of the plant, is 
evidenced by the rise of the sap in spring, and its return in 
autumn, as seen in the fall of the leaf. In the first case an im¬ 
mense supply of liquid and gaseous matter is forced or drawn up 
from the roots, and in the latter a due proportion is returned 
after elaboration for their nourishment and increase through the 
winter. It follows, then, that to remove a plant in spring after 
this action has once commenced, is to subject it to a very 
serious check through an insufficient supply of food; for with the 
utmost care it is impossible to take a tree or shrub from the place 
where it has been growing in the ground, without injury to its roots, 
the smaller fibres, which are the most active organs, being the 
most readily damaged, and in plants of size by far too numerous 
to be entirely preserved. As the roots are to be regarded as the 
absorbing organs, so the leaves have been determined to possess 
a powerful perspiratory action, and it is the exhaustion con¬ 
sequent on this waste, that renders the removal of deciduous trees 
impossible in a growing state. 
Hales, an accurate observer, ascertained that a sunflower three 
feet and a half high, perspired in a warm day thirty ounces 
avoirdupois; and if we draw a comparison between the evaporating 
surface'of such a plant, and the area of the almost numberless 
leaves of what would be called an ordinary sized elm or lime tree 
for removal, we may form an idea of the demand such a subject 
would make upon its roots, was it only to supply positive evapo¬ 
ration, without regard to what should be present for secretion. 
And it should be remembered, this perspiring action is always 
great in proportion to the action of the sun, so that our spring- 
