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some extent affecting the hardihood of the trees. The cells of both Food and fruit, the leaves, the branches and the pores, all are so enlarged in our improved trees as to retain only a semblance of the native stock from which they were derived. With the structural parts so enlarged comes countless blights and diseases, which have, in the course of a few years, spread to all parts of the land. To some of these diseases, also to the structural change which takes place in the amelioration of fruits, we shall again briefly refer.
Orders for nursery trees are generally given to nurserymen residing north of the place where the trees are to be planted. This is done under the impression that northern grown trees are hardier than trees grown at home or south. When or how this conclusion was arrived at we do not know; tha: it is erroneous we think may be shown. For example, if we examine trets grown far north, we find that their growth is often checked by frost at a time when the new cells, although perfectly formed, were yet soft. These sott cells resemble more those of succulent than hard wood plants. There will also be found to be present a large supply of unorganized materials for the formation of other cells which cannot be elaborated by the tree in its present condition; these young trees are therefore gorged with crude juices, which are greatly expanded by the severe frosts of winter; the new cells are burst, and the unorganized materials in the tree ferment and destroy the healthy parts with which they are in contact. On the other hand, trees grown very far south are, on tae approach of winter, sometimes in a situation so similar to trees grown at the north, as to deserve a passing remark. Owing to the great length of the warm season, trees at the south often cast tbeir leaves at midsummer, and after a short period of rest they make a second growth of leaves, which cannot be matured before they are killed by the frosts of winter. When this occurs, both the northern and southern trees are in the same condition; both are largely supplied with crude matter which they cannot mature, and hence the trees of both sections will be found to be tou tender to withstand, uninjured, our mildest winters.
If the facts we have stated are borne in mind, they will afford a clue to the treatment trees should receive at the two extremes of latitude at which it may be desirable to grow them. For instance, a tree at the north should be so treated as to enable it to mature its growth some days or weeks earlier than they would do if cultivated as they commonly are. On the other hand, trees grown at the south should receive such culture as would prolong growth to as late a period as possible, and thereby avoid the summer rest and tenů ency to a second growth. If these conditions are secured, the trees of both sections will be as hardy as those which grow at an intermediate point, where they mature at the proper time without artificial aid.
SPONGIOLES OR BOOT HAIRS.
The removal of trees necessitates the loss of by far the larger part of their small fibrous roots, but not of spongioles, as is erroneously supposed, since, at
the time trees are at rest, their roots are destitute of spongioles. That this is so may be known by inspecting the roots in the spring. At this season of the year roots will be entirely destitute of spongioles, but as the period of growth arrives, from their sides, especially of the smaller roots, will appear many small warty excrescences. These excrescences are made up of a vast number of little bladder-like cells; each new cell, as it enlarges, divides into two, and each of these again divides and is added to those already made. In this way it is, by the multiplication of cells, that new roots, as well as other parts of trees, are formed. It is to the sides of these newly formed rootlets that the spongioles are attached. These spongioles, or root hairs as they are sometimes called, are not roots, nor do they ever become such, any more than leaves abcve ground become branches. The office of the spongioles appears to be to extract food from the earth needed by the tree in the season of growth; they act in concert with the leaves, and in the autumn they separate from the roots. Therefore, from the fall of the leaf until growth commences in the spring, all our deciduous trees may be said to be spongioless as well as leafless.
Shall we grow our trees with branches starting from the ground, or shall we prune; and to what height? These and similar questions are now often asked. We think it would be superfluous to give any instructions in growing fruit trees to low heads, since for the past sixteen or eighteen years all our journals, both horticultural and agricultural, have vied with each other in descriptions how best to accomplish, as they supposed, so desirable a result. Indeed so much has been written on this point that we have gone from trunks six to eight feet high down to those of as many inches. These low-headed orchards, on coming into bearing, have disappointed, or must soon disappoint, their owners. The conditions attending the growing fruits are now so changed from what they were but a few years since, that trees with low heads are in the main no longer a success.
They increase the labor of cultivation many fold. The low branches cut off the under circulation, inducing disease in the foliage and not in the fruit. They invite insect enemies, and make it difficult if not impracticable to arrest their ravages. In short, low heads are a failure, and the sooner we can induce people to start the heads of their trees at a proper height, the sooner will it be possible to successfully destroy insects, to ward off diseases, to insure color to the fruit, and make it practicable to cultivate quite up to the trees by means of horse power.
In planting an orchard we select trees according to their kind-apricot, peach, plums and cherries, one year old, from bud or graft; apples and pears, two and three years old.
The four first named, if well grown, will be not less than five or six feet high, and will have many side or lateral shoots branching out horizontally irom the main or vertical stem. In addition to the side branches, there will also be found numerous buds, extending from the ground to the top of the tree. Cut away all the branches and buds to the height of twelve or fifteen inches. Next cut away all the buds below the point at which it is intended the tree shall form its head, except six or eighit buds, which are to be left at regular intervals and on different sides of the stem. These last mentioned buds will push into as many branches as there are buds. It will be necessary to keep these side branches pinched back to ten or twelve inches during the summer, to prevent them from running off with the growth and robbing those buds and branches selected for the future head of the tree. Sometime after the fall of the leaves and before growth commences in the spring, reduce the side branches to one bud each, and when the branches from these buds shall estend to ten or twelve inches, pinch them as directed in the first year. The treatment will be the same the third year as we have directed for the second, except at the end of the season cut away all the side branches except those intended to form the head of the tree. The object of the side branches, of which mention has been made, was to strengthen the stem or trunk of the tree. Without them the trees would have become top-heavy and bent the trunks. Trees grown as we have described will have straight and tapering stems, which will be of sufficient strength in their fourth year to stand erect.
BUDS, GASSES STORED, ESCAPE OF GASSES, CAUSE OF DEATH, ETC.
To show the effects which frost, overbearing, and succulent growth have on the fruit buds of orchard trees, it will be necessary that we briefly de scribe those parts of the bud to which we shall refer. The buds of stone fruits of orchard trees may be separated into two classes. First, those which contain single germs of fruit, as the apricot and peach. Second, buds that inclose several germs, of which most varieties of the cherry are examples. Since the structure in both of these classes of buds differs only in so far that several of the latter are folded in one envelope, a description of one class will answer our purpose for both. The germ of all our stone fruits at first consists of a single cell, and this is situated in a small cavity, which, according to some botanists, consists of an embryo leaf, folded by the tree into : form much like a vase, but more tapering at the top; the sides or wall of the cavity thus formed is made up of numerous small cells. To appearance these cells are built up around the germ cell much as a mason would inclose a conical space with brick, with the ends pointing to the center. The cells at first are soft and readily press together so as to perfectly touch each other and make a close wall. The forms of these cells differ from wood cells in so far that the exterior and interior surfaces are not pressed upon by other similar cells, as in woody structure, and hence they appear, when viewed from either surface, to be of an oval form.
The parts of the bud we have described, and to which we shall refer, are covered with the corolla, which is the colored part of the flower, the calyx, which forms part of the envelope of the bud, and the scales, which inclose the whole.
Large and improved varieties of fruit we produced only on trees which have much larger wood cells, annual twigs and leaves, than seedling trees or those with small fruit. The buds of improved varieties are also large, and the scaly portions covering the interior parts of the bud are folded together more loosely than in smaller ones; so large and loose are some of these exte
rior scaly coverings, as in the Melocoton family of peaches, that it frequently happens that moderate freezing of the buds, especially while they are wet, partly unfolds them, so as to admit of the escape of what is believed to be carbonic acid gas, which, so long as it remained, protected from frost the little wall of cells which inclosed the fruit germ, as in the peach. Gasses or fluids not only inclose and protect from the effects of frost the exterior wall of the cells that surround the germ cell, but tbe cavity in which the germ cell is inclosed is also filled with carbonic acid gas or other fluid, as has been ascertained by puncturing, and to which experiment we shall again refer.
Hence it never occurs that the germ cell, or the interior surface of the wall of cells surrounding it, can sustain injury until an opening is made in the wall by separating one from another the cells of which it is composed. But so soon as an opening is made the gasses or fluid escape and the germ is killed.
That the escape of gasses or fluids stored in fruit buds is destructive to them, as well as to the embryo leaves inclosed in the leaf buds, may be known by piercing the buds with a small broach not larger than a hair. If this is done in cold weather, the bud, whether it be leaf or fruit bud, is immediately killed by freezing; but if we perform the operation on a warm day, the bud will retain its vitality until frozen. If we delay, and puncture the bud after freezing weather is past, then the germ of either leaf or fruit will grow as though the puncture had not been made, except that in the leaf a small hole will appear, and the fruit will develop a scar at the wounded part.
It not unfrequently occurs that, very early in the spring, a small brown fly pierces the side of the wall of cells to obtain the sweet substance stored within. This it often does without preventing the growth of the germ.
In view of these facts it appears that the gasses or fluids are stored in the buds of trees only as a protection against frost. It will be asked, if the buds are protected against cold as we have stated, why the leaf buds are not killed at the same temperature that kills the fruit buds? The answer to this is, that the fruit buds have a larger share of nutriment stored in and around them, with which to commence growth, than is stored in leaf huds, and it is perhaps on that account that the fruit buds are most excited and are first to expand. But, most of all, the less power in the fruit bud to resist extremes is due to the premature separating of the calyx and scales covering the bud, induced by growth of the interior parts of the bud. This inside growth of the bud is due to the increase in size of the individual cells that surround the germ, and as these enlarge they expand the outside coverings of the bud, so as to make them more susceptible to moisture and ruptures by frost.
Therefore, the power of buds to resist cold is determined by the condition of the buds at the time the freezing occurs. For example, in the winter of 1856 and 1857, at Alton, the thermometer indicated 20 deg. below zero, and when carried a few feet away from the buiiding it sank to 27 deg. below zero. Notwithstanding the severity of the cold, the Alton district was, the following summer, noted for its great yield of peaches. Our observations at the time went to show that the injury to the buds was only as one in eight.
Perhaps at this point we ought to explain the conditions combined to produce such favorable results. The trees having borne no fruit the summer preceding the winter to which we have referred, continued to grow until near the period of frost. There was, therefore, no premature swelling of the buds, as is quite common in the fall. The scales covering the interior parts of the buds were closely folded. Even the large and pointed buds of the Crawford's early and late varieties, which are classed among the tender peaches, were in a condition seldom seen at so late a period. The ends of the calyx and scales, which in these varieties usually appears to be partly open at the end of the bud, were so closely folded as to exclude moisture. In short, the buds were perfectly developed, and, up to the time of the severe freezing, had not frozen in the least, and were, on that account, in a condition to resist the lowest temperature possible for buds of the peach to endure.
Perhaps no injury sustained by fruit buds more common than the bursting of a single cel! in the wall inclosing the germ-cells. When hard freezing occurs, it sometimes happens that some of the cells pointing at the outer surface are ruptured; when this happens to only one cell, the exterior coating of the cell is held in place, and the fruit grows as though the injury had not occurred; except at these wounded places a scar will appear on the surface of the fruit. Also, in the early stages of growth, these wounded parts afford resting places, to which some of the cryptogamous plants attach and rot the fruit.
All our orchard fruits are more or less liable to this casualty, but most some varieties of pears; next, the English Morello, the Heart, and some of the Bigarreau cherries; peaches and plums somewhat less, and, as a rule, apples least. The germs of all fruits are most liable to injury in the way we have described the winter after they have produced heavy crops.
When two, three or more contiguous cells are burst, the fruit-germ generally perishes within a few hours or days, or, if the bud blooms and the fruit matures, the scar remains and arrests growth at the wounded part. When sereral ruptures occur, but on different sides of the wall surrounding the germcell, and the fruit matures, as is sometimes the case with some varieties of apples, then the fruit becomes knobby and of little value.
It not unfrequently occurs that fruit buds are changed to wood buds in the season of growth; this takes place only in trees, or parts of trees, that are making a very succulent growth.
All who are familiar with the practice of budding the peach will readily call to mind examples of this in stocks budded early in the season. If, under a microscope, we examine fruit buds taken from a tree of very succulent growth, we find in some the single cell or fruit-germ is wholly wanting ; in other buds it is present, but the little wall of cells, of which we have previously spoken, is incomplete, one side being built up to the proper height, while in another part much is wanting, and in others the wall cells are so loosely placed as to suggest the possibility that many of the little cells had perished, leaving openings that remind one of a brick wall with many of its bricks pulled out.