CUTTING THE LEAVES OF PEACHES AND NECTARINES. 541 
When tlievefore we remove a sound, healtliv leaf, we deprive the plant 
of one of those organs by which its vital functions are maintained. 
In respect, therefore, to the first observation noticed by Noctura, 
"that trees receive great advantage if planted with their leaves on," 
it is true to the letter, that if a young tree be removed in September, 
when the leaves retain their verdure, //ts A Jtbrous roofs ivill be 
emitted ; and as I have lately seen, these leaves may even remain 
firm and green beyond their usual period. But these appearances 
are dece])ti\'e, in as much as regards the future growth of the }'Oung 
tree ; for, the energy of the plant is exerted in causing the protrusion 
of fresh Jibres , instead of causing the deposition of the proper juices 
in and among the vascular cells of the inner bark (Liber), and the 
sap-wood, (Alburnum.) Now, Mr. Knight has proved that a jior- 
tion of the true sap is conveyed through the channels of the conver- 
gent i^rocesses (formerly termed the mp.dullary rays) into the 
alburnum ; and the deposition thus produced is doubtless one of the 
chief requisites for effecting the perfect ripening of the wood. If 
then the reservoir of prepared fluids be expended in the protrusion 
of roots instead of being hoarded up during the torpid season, the 
future spring growth must be materially injured. 
Trees therefore ought, perhaps, to remain undisturbed until the 
leaves have fallen ; after which period, I doubt much ivhether a 
single Jibrous root is ever produced till the early spring influences 
begin to prevail. 
The agencv of the leaves in ripening the fruit is another con- 
sideration. During the blossoming season, and until the fruit has 
acquired its full immature growth, the leaves are essential to its 
progress ; but when nothing remains to be effected but the process 
of maturation, the agency of light is jjerhaps of paramount impor- 
tance. There is a curious and most interesting paper on this 
subject in the fort}- -sixth number of the Annales de Chimie et de 
Phisique, February, 1831, by M. Couverchel. It was read before 
the Academic des Sciences of Paris on the 10th of May, 1830, and 
contains the detail of a vast variety of interesting experiments ; 
from the general results of w^hich, the writer arrives at the conclu- 
sion, that, the process of maturation may be, and is, perfectly 
effected after the fruit is detached from the tree. I venture to 
transcribe a passage from the original Memoire, as it is found in 
page 187. 
"La maturation des fruits a pericarpes charnus, s'opere par la 
reaction des principes qui entrent dans leiu* composition. II est a 
presumcr, comme nous 1' avons dit, que la seve s'acidefie dans son 
