THE ORGAKS AND PARTS OF PLANTS. 



3 



1.-^ Leaves. 



These, as is well known, are the upper appendages of 

 plants, which give them nearly all theii* beauty, and are the 

 means by which they expand and become strong. They 

 are the instruments of elaborating all food^ and giving ofi" 

 its watery parts. It is in them that the processes analo- 

 gous to digestion and assimilation in animals ai'e carried 

 on. Through the action of light upon them, they separate 

 the nutritious from the watery portions of the sap, and 

 discharge the latter into the air, while they restore the 

 fonner to the branches and stems. AYhen, therefore, by 

 bu'ds, or insects, or disease, or the browsing of cattle, a 

 plant is stripped of its leaves, it will either become weak 

 and sickly, or altogether die. And the more abundant and 

 healthy the foliage of a plant may be, the more vigorous 

 and luxuriant will be its general growth. To pluck leaves 

 from plants with the view of aiding fruit or wood to ripen, 

 or at all to anticipate their falling off in the Autumn, is a 

 great error ; for it is through the leaves alone that both 

 wood and fruit are enabled to reach matiuity. 



It must not be supposed, however, that encouragement 

 i^hould be offered to the growth of leaves in all cases. A 

 frait tree or a flowering plant may sometimes settle into 

 a thoroughly unprolific state, in consequence of undue 

 luxuriance in leaves and wood. The corrective will then 

 be found, not in reducing the number of leaves by thinning 

 them, but by pruning the branches, or descending to the 

 source of the evil, and impoverishing or pruning the roots. 

 This is merely mentioned to show that, although leaves 

 are most necessary, and their action beneficial, they may, 

 in particular instances, become too numerous, and thus do 

 mischief. There is a kind of balance preserved by ^STature 

 in plants, between the leaves and the roots ; so that where 

 the one is particularly strong or feeble, the others will be 

 sympathetically strong or feeble also. Whatever tends to 

 increase or diminish the one will therefore similarly affect 

 the others. Roots may be very vigorous, and require 

 pruning, as already suggested, because they occasion the 

 production of too much wood and foliage. And because, 



