THE CULTIVATOR. 
7 
boiling. If the lips of the finger-cut accordingly be kept close toge 
ther by sticking plaster, they will become united by means of this 
natural glue, or serum, in little more than a day. Upon the same 
principle, I once succeeded, as others have done, in managing to unite 
the whole up-joint of a finger which a boy had chopped off by ma¬ 
chinery ; and experiments have been successful in causing the spur 
of a cock to unite and grow upon his comb. 
“ It is upon similar principles that the science of grafting is found¬ 
ed ; for if a young branch, like the boy’s finger, be taken off by ; 
clean cut, and the cut extremities immedidately joined, the descend 
ing pulp will thicken like the watery part of blood, and while it re¬ 
mains soft, the sap from the cut end of the sap vessels will force its 
way through to their continuation above in the cut slip, which, if the 
process be successfully managed, will grow as well, or nearly, as if 
it never had been cut. 
“ If again, instead of applying the same cut scion to the part it was 
cut from, a scion from another tree be applied, as if I had applied to 
the boy’s finger the tip of another boy’s finger, chopped off by the 
same accident, there seems no good reason to doubt that a similar 
healthy joining might, by care, be effected. In the case of animals, 
indeed, such joinings are rare, because rarely tried; but in garden 
plants they are exceedingly common, for the purpose of continuing 
esteemed varieties of esteemed fruits and flowers accidentally produc¬ 
ed by cultivation, as well as for forwarding the fruiting of young 
trees—since seedlings require years to arrive at a bearing state. 
“ 0° examining the joining of a graft about a fortnight after it has 
been made, I have found, as in a healing finger-cut, a number of 
small roundish grains, in form of a thin layer, produced from the 
thickening of the pulp, and destined to form the hard substance term¬ 
ed the callus, which in general projects a little externally, and the 
scar differs in appearance from the other parts of the bark. It is, 
however, only in the space between the pulp-wood and the bark that 
the uniting substance is formed, and therefore it is evident that the 
slip to be grafted must have this part applied to the same part of the 
stock, and, if these differ in thickness, at least to one side.” 
“ One of the most obvious principles of this process is, that the 
scions to be grafted should be alike, or nearly alike, because, in that 
case, the arrangement of the sap and pulp vessels being similar, their 
cut ends will more readily apply mouth to mouth, and less obstruc¬ 
tion, or interruption of the circulating juices will take place. 
“To this principle there is an exception, arising from the pecu¬ 
liar design which the graft is intended ta fulfil. . When the design 
is to increase fruit bearing, the stock may be of finer texture than the 
cutting, as when a peach cutting is grafted on a plum stock, which 
having narrow vessels, a part of the .descending pulp is stopped short, 
and seems to strengthen the branch. If it be intended to increase 
the branches and leaves on the other hand, a plum cutting grafted 
on a peach stock might probably do so, by allowing the ascent of 
more sap. 
“BINDING OF THE GRAFT. 
“ When the joining has been made by cutting and properly fitting 
the bark of the slip to the bark of the stock, at least on one side 
thereof, it must be bound so as to prevent this junction being de¬ 
ranged. This is usually done with a ball of three parts of clay, well 
worked with one part of fresh horse droppings, and a little finely 
chopped straw, the whole about an inch thick, and two inches or 
more in length, being tied with a ribbon of bass.” 
“ The principle upon which this is done, is to prevent the oxygen 
of the atmosphere from getting to the fluid pulp at the joining, where 
it would unite with the carbon, and form carbonic acid gas, and there¬ 
by rob the pulp of its solidity. The exclusion of light is necessary 
on the same account, for, as in the case of a finger cut, the oxygen 
would unite with the carbon, and prevent the thickening of the matter 
from the blood. On the same account, moisture, by supplying oxy¬ 
gen, would be injurious ; and dryness might act both by exhausting 
the pulp, and by causing the edges of the bark to shrivel and gape, 
which would facilitate the entrance of the air and its oxygen.” [For 
the particular modes and process of grafting see p. 18, vol. ii. of Cul¬ 
tivator.] 
PRUNING. 
We have been the constant advocate for summer, instead of win¬ 
ter pruning—of pruning after the leaves have expanded, and the 
limbs have nearly or quite completed their vernal growth, in prefe¬ 
rence to pruning when trees are leafless, and the growth dormant. 
We have done so because we considered it most rational in theory, 
and have found it more beneficial in practice. As it is the general 
practice to to prune fruit trees at this season, we will recapitulate 
the reasons which have influenced our practice. 
1. Winter pruning causes an increase of spray, or weak limbs, 
which it is the object of the cultivator to lessen, in order to admit the 
light, heat and air into the head of the tree, to perfect and mature 
the fruit. On this point we quote Prof. Rennie. 
“ The head or branches,” he observes, “ will always be in propor¬ 
tion to the roots, and the food with which they are furnished. It 
will therefore be obviously preposterous to dream of checking the 
luxuriance of a tree, by cutting out its branches in autumn or win¬ 
ter ; for no sooner does the sap begin to flow in spring, than fresh 
branches will arise from the strongest branch buds below where the 
pruning was made, and the same quantity of sap being furnished, 
the tree will very soon be as luxuriant as before the operation. Fre¬ 
quently it will be more so, for the pulp laid up in the roots the pre¬ 
ceding autumn will be more apt to cause new root fibres than in an 
unpruned tree. So true is this, that weak old trees are often head¬ 
ed down to render them luxuriant; though the same gentlemen will 
also extensively top luxuriant trees in winter, with the hope (certain 
to be frustrated) of checking their growth. Summer pruning, how¬ 
ever, has a different effect; and When young shoots and suckers are 
thinned off in summer, they prevent a tree from exhausting itself.” 
—Alphabet of Sci. Gardening. 
2. Winter pruning leaves to the sun and winds, at the worst sea¬ 
son of the year, and for a long time before the healing process can 
commence,' the wounds of the amputated branches. The cut part 
either dries and checks, making a lodgement for rains, and causes dis¬ 
ease and death, or the sap exudes from the wound, producing canker 
and corroding the bark- 
3. Both of these evils are averted by summer pruning. New 
sprouts are seldom thrown out, and the diminished flow of pulp, or 
elaborated sap, is expended in healing the wounds, by covering them 
entirely, or the edges, with new wood, and in the formation of 
buds. 
It should be borne in mind, that light, heat and air, are all neces¬ 
sary to develope the excellence of fruit. Without their co-operation 
fruit neither at tains its natural colour, consistence nor flavor. Light 
is necessary to give substance, hardiness and colour. Heat is indis- 
pensible to the active circulation of the sap and the formation of su¬ 
gar, or the principle of flavor. And air is necessary in modifying the 
sap while undergoing the elaborating process. Hence the utility of 
exposing fruit to the influence of these agents, by thinning the wood 
upon fruit trees. In the apple, especially, it is advisable to train its 
top in the form of an inverted funnel, by cutting out the leading up¬ 
right shoot, as soon as three or four arms or branches, at a proper 
height, are sufficiently advanced to receive and elaborate the sap 
coming from the roots. Upright wood does not produce fruit like 
that which inclines, or grows nearly horizontal. So that taking out 
the leading stem not only produces more, but better fruit. As leaves 
are as necessary to the formation of roots, as roots are to the forma¬ 
tion of leaves, in pruning, one-third of the stem should at least be left 
untouched by the pruning knife. 
FACTS IN AGRICULTURAL SCIENCE. 
ANALOGY BETWEEN ANIMAL AND VEGETABLE NUTRITION. 
Animal and vegetable matters constitute the food of animals and 
vegetables; yet these matters nourish neither the animal nor the 
vegetable, until they h.ave undergone certain preparatory processes, 
and are reduced, to a fluid state. Solid substances, so long as they 
remain solid, can benefit neither. 
The soil is to plants what the stomach is toanimals—the recipient 
of food—where it undergoes its first process of preparation, is broken 
down and blended with a solvent liquid. 
The spongeoles, or small roots of the plants, like the lacteals in 
the animal, take up the digested food, and send it to the leaves, as 
the lacteals do to the lungs, for its perfect preparation as food. 
Leaves are to plants what lungs are to animals—the organs of 
respiration. The lungs retain oxygen and give off carbon. The 
leaves part with oxygen and inhale carbon, when the sun shines up¬ 
on them, and imbibe oxygen when it does not. Leaves are, in sum¬ 
mer, as necessary to the health and growth of the vegetable, as lungs 
are to the health and growth of the animal. 
Heat, air and water are essential in all the processes of nutrition, 
vegetable as well as animal. 
The ordinary temperature of the animal stomach is 98°—hence 
animal digestion does not abate for want of heat. The decomposi- 
