100 The Root. [March, 



that food is not at hand, they are often found elongating themselves 

 into crevices and fertile places, in an extraordinary manner, in search 

 of it. The modern theory for explaining the reasonableness and 

 necessity of a rotation of crops, is on the principle that plants ex- 

 haust the soil of certain substances, and excrete others ; and that 

 what is taken in by one class of plants, is not demanded in the same 

 proportion by others, and in this way, by proper rotation, the fer- 

 tility of the soil can be preserved, if not improved. 



The fluids thus taken up by the spongioles, holding in solution 

 the various ingredients adapted to the plant, has been compared to 

 the circulation of the blood in animals, as it is by this means nour- 

 ishment is supplied to the plant. The fluids thus entering the roots 

 by innumerable little mouths, rise upward, filling the cells, and 

 being borne onward to the leaves — answering to the lungs of the 

 animal — an elaboration takes place, thus supplying an excess of 

 nourishment, causing new cells to be produced, and thus increasing 

 the size, by widening and lengthening the cellular tissues. We shall 

 have more to say of the circulatory motion of the fluids when we 

 come to the stem and leaves, as it more appropriately belongs to the 

 discussion of these parts. The practical cultivator can not give 

 too much attention to the nature of roots. It is upon their proper 

 treatment that his success principally depends. And yet many han- 

 dle a tree as though these delicately formed and tender filaments of 

 roots were of little value. Treating it as though it were a post or a 

 handspike ; simply realizing that one end is to be put into the ground, 

 and concluding that if the weather is wet enough, when he sets it, 

 and the season should continue wet, he would sui-ely realize his fond 

 wishes. On the contrary, he should regard his tree in taking it up, 

 and handling it when up, and in replacing it in the locality intended, 

 as a delicately formed, organized body, with important functions ; 

 indeed, further, a living body, to whose nature, in removing, he had 

 done great violence, and produced a shock, which, with all his care, 

 can rarely be placed in such favorable circumstances, as to renew 

 and enter every part upon its own appropriate offices, and perform 

 its former functions. If we understood more of the nature and 

 functions of every part of our plant, how very carefully would we 

 proceed in all these difficult, thcjugh oft repeated and familiar opera- 

 tions ! If these little spongioles of the root, for instance, are so 

 necessary, and in removing they are subject to be broken off, dried, 

 frosted, or on being replaced, starved, we must be mindful of the 

 laws which govern in the case, and act in conformity thereto. 



