22 
THE FOOD OF TREES IS IMBIBED [Part II. 
Experiments 
in proof. 
Seedlings not 
nourished by 
roots till they 
become woody, 
but by the seed. 
in the ordinary course of nature, the sap should 
perpetually flow both ways at once in the same 
channel . 
As this question is of vital importance in trans¬ 
planting, I will state the results of several expe¬ 
riments in support of these opinions. To begin 
again with the seedling. In March, 1836,1 made 
some horse-chestnut seeds grow in water, in my 
barrack-room, and found that when the root was 
cut off when it was several inches long, the plant 
would still grow, and would continue to throw 
out fresh roots as fast as they were cut off. The 
existence of the plant was evidently independent 
of the root. The reason is, that unripe, that is 
unwoody, roots are incapable either of absorbing 
or of transmitting sap; but receive their own 
nourishment from above,—in this case, from the 
seed. Consequently, whenever I divided a plant 
from its seed, it died, though the root was 
perhaps twice the length of the plant, and 
though leaves were developed on the plant. Yet, 
when I allowed the seeds to remain attached to 
the plants till the roots had become woody, the 
plants grew in water for years. Moisture is taken 
up by absorption from the surface of the seed; 
the elaboration of the sap is entirely in the seed, 
and passes through the bands which unite it to 
the seedling, for the growth of the plant upward 
