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COCOON AND PUPA.
gradually to spread from thence in every direction, and appeared in New Hampshire, near the northern limit of the peach region, in about the year 1805, and has since extended to the southern states, and west of the Alleghany Mountains. “The eggs, from which these borers are hatched," says Dr. Harris, "are deposited, in the course of the summer, upon the trunk of the tree near the root; the borers penetrate the bark, and devour the inner bark and sap-wood. The seat of their operations is known by the castings and gum which issue from the holes
in the tree. When these borers are nearly one year old, they make their cocoons either under the bark of the trunk or of the root, or in the earth and gum contiguous to the base of the trees; soon afterwards they are transformed to chrysalides, and finally come forth in the winged state, and lay the eggs for another generation of borers. The last transformation takes place from June to October, most frequently, however, during
the month of July, in the state of Massachusetts. Here, although there are several broods produced by a succession of hatches, there is but one rotation of metamorphoses consummated within a year. Hence borers, of all sizes, will be found in the trees throughout the year, although it seems to be necessary that all of them, whether more or less advanced, should pass through one winter before they appear in the winged state. Under its last form, this insect is a slender, dark-blue, four-winged moth, having a slight resemblance to a wasp or ichneumon fly, to which it is sometimes likened. The two sexes differ greatly from each other; so much so, as to have caused them to be mistaken for two distinct species. The male, which is much smaller than the female, has all the wings transparent, but bordered and veined with steel-blue, which is the general colour of the body in both sexes; the palpi or feelers, the edges of the collar, of the shoulder-covers, of the rings of the abdomen, and of the brush on the tail, are pale-yellow, and there are two rings of the same yellow colour on the shins. It expands about one inch. The fore-wings of the female are blue, and opaque, the hind-wings transparent, and bordered and veined like those of the male, and the middle of the abdomen is encircled by a broad, orange-coloured belt. It expands an inch and a half or more. This insect does
not confine its attacks to the peach-tree. I have repeatedly obtained both sexes from borers inhabiting the excrescences which are found on the trunks and limbs of the cherry-tree; and moreover, I have frequently taken them in connection on the trunks of cherry and of peach-trees. They sometimes deposit their eggs in the crotches of the branches of the peach-tree, where the borers will subsequently be found;
but the injury sustained by their operations in such parts, FEMALE.
bears no comparison to that resulting from their attacks at the base of the tree, which they too often completely girdle, and thus cause its premature decay and death."* Hitherto, various means have been resorted to for repelling or destroying these vile offenders, and many of them have been more or less effectual, but none have been attended with complete success, except in removing the earth from the base of the tree, and crushing the borers to death, and destroying the eggs and cocoons. A small quantity of leached wood-ashes, or of newly-slaked lime, added to the roots and then covered with earth, has proved advantageous, not only in warding off the borers, but in promoting the vigour of the trees. On this subject, Judge Peters remarks, in the "Memoirs of the
* See Harris' Report, p. 233.
Philadelphia Society for promoting Agriculture,” that he had “failed in many things, in which others are said to have succeeded. Straw and bass, or paper, surrounding the tree, from the root, at all distances, from six inches, to three or four feet, white-washing, painting, urinous applications, brine, soot, lime, frames filled with sand, oil, tar, turpentine, sulphuric acid, nitrous mixtures, and almost every kind of coating. I ruined several trees, by cutting them down, and permitting the stump to throw up new shoots, and branch at pleasure. All teguments kept the exudation from evaporating with freedom. The pores being closed, or too open, were alike injurious. Teguments of straw or bass, made the bark tender; and it threw out, under the covering, sickly shoots. The more dense coating stopped the perspiration. The oil invited mice, and other vermin, which ate the bark thus prepared for their repast, and killed the tree. I planted in hedge-rows and near woods-I paved, raised hillocks of stone-I have suffered them to grow from the stone only, grafted on various stocks, and budded, hilled up the earth in the spring, and exposed the butt in the fall—sometimes I have used the knife freely-frequently have left the tree to shoot in every direction-I have scrubbed the stocks or trunks with hard brushes, soap-suds and sand, scraped them with proper instruments; I have, for a season or two, under various experiments, amused myself with the persuasion, that I had discovered an infallible panacea. I had temporary success, but final disappointment.” “I remove the earth, a few inches round the tree in August or September, pour around the butt, beginning about one foot above the ground, a quart or more, (not being nice about the quantity,) of boiling-hot soap-suds or water. This kills the egg, or worm lodged in the tender bark; and of course prevents its ravages the next season. I carefully search the trees, though I seldom find worms. I do not perceive any injury from this operation. I have discovered worms in or near the roots of the smallest stocks taken from the nursery. These I frequently plunge into boiling water, before planting. I lose very few; and do not attribute the losses to the hot water."
The peach-tree also sometimes suffers severely from the attacks of leaf-hoppers, (Thrips,) as well as from those of the true plant-lice (Aphides.) They are found beneath the leaves, in small cavities produced by their irritating punctures, and are so small that they may readily escape notice. These minute insects have very slender bodies, and narrow wings, which are fringed with fine hairs, and lie close to their backs when they are at rest
. They are exceedingly active, and appear to leap, rather than fly, when they move. The plant-lice, likewise live under the leaves of the peach, causing them, by their punctures, to become increased in thickness, to curl or form hollows beneath, and corresponding crispy and reddish swellings above, and finally to perish and drop off prematurely. The depredations of these lice is thought to be one of the causes, if not the only cause, of the peculiar malady affecting the peach-tree in the early part of suminer, known under the name of "
“blight. The most efficacious means employed for the destruction of the thrips and aphides are fumigations of sulphur, tobacco, or other acrid substances, and throwing into the trees, with considerable violence, warm solutions of tobacco and water, soap-suds, and even pure water.
The fruit of the peach-tree is punctured in an early stage of its growth, by a small, rough, dark-brown beetle, (Curculio nenuphar, Herbst,) for the purpose of depositing her eggs, and thereby providing for her future progeny. When a peach is stung by these beetles, a small drop of gum may be seen oozing from its surface. The larvæ consist of little whitish grubs, which bore into the fruit, and cause it to fall before it is mature. For a further account of this insect, the
* Harris' Report, pp. 187 et 192.
reader is referred to our article on the domestic cultivated plum, under the head of “ Insects.”
The seventeen-year locust, (Cicada septendecem,) although most usually found on the oak, often resorts to other forest trees, when actuated by necessity, and not unfrequently deposits her eggs on the branches of the peach-tree, when no other convenient shrub or tree is at hand. Peach-trees once attacked by this most pernicious insect, seldom, if ever, recover from the inflicted wounds.
Among the diseases incident to plants, there is no one involved in more mystery than that strange disorder in the peach-tree, commonly called the "yellows.' It was noticed in the neighbourhood of Philadelphia, by Judge Peters, in 1790, or the year following. From perfect verdure, he states, the leaves of his trees turned yellow in a few days, and their bodies blackened in spots. He attributed the origin of the disease to some morbid affection of the air, which he conceived has the most to do with all vegetation, as well in its food and sustenance, as in its decay and dissolution. From Philadelphia, the malady spread, by degrees, to other parts of the country; and by 1810, in New Jersey, there were left but a few peach orchards alive, or in a flourishing state. It is said to have appeared in the vicinity of New York, in about the year 1801; in Connecticut, in 1815; and in Massachusetts, in 1824. It is also prevalent in the southern states of the union, and west of the Alleghany Mountains.
The phenomena attending the development of this disease, are given in detail, in the second number of the "Albany Cultivator," of 1845, by Mr. Noyes Darling, of New Haven, from which we make the following condensed extracts :“There are two marks or symptoms, by which the presence of the disease is indicated. One is, the shooting out from the body or limbs of the tree, of very small, slender shoots, about the size of a hen's quill. The leaves upon these shoots are commonly destitute of green colour, as if blanched, or as if grown in a dark cellar; and like the shoots which bear them, are of diminutive growth, rarely exceeding an inch in length. These shoots do not usually start from the common, visible buds at the points where the leaves join the stem, but from unseen, latent buds in the bark of the trunk or large branches. The other symptom is, the ripening of the fruit two to four weeks before its natural season of maturity. Most generally also, the fruit, whatever be its natural colour, is more or less spotted with purplish-red specks. If shoots, such as are above described, appear upon a tree, or without them, if the fruit upon any part of it (not wormy) ripens before the proper time, it may be certainly known that the tree has the yellows. These are not the only marks or symptoms of the disease; but they are those which are the most readily discovered. The ordinary leaves of the tree, or at least those upon the diseased portion of it, commonly undergo a slight change of colour. Instead of a bright glossy green, they take on a dull yellowish tinge. The wood also, when the disease is considerably advanced, becomes unelastic, so that its branches, when moved by the wind, instead of the graceful waving of health, have a stiff jerking motion. * * * * * The fruit, the first season of attack, usually grows to its proper size. The second season, it is uniformly small, not more than a half or a quarter of its usual size. Whatever be the natural colour of the fruit, red, yellow, white, or green, it is more or less, when diseased, coloured with purplish-red; generally in specks, or coarse dots. The flesh, quite to the stone, is often coloured, and most deeply around the stone. By the coloured specks, a person may easily distinguish by the eye, diseased, from healthy fruit.
In the first summer of disease, it is not always that the whole tree appears affected. The slender shoots may show themselves on one branch only, the rest of the tree having every appearance of health. In like manner, the fruit upon one branch may ripen four weeks too soon, upon another two weeks too soon, and upon the rest of the tree at the natural time.
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The second season, all the fruit will ripen three or four weeks too soon. The tree sometimes dies the next year after the appearance of the disease, and sometimes lingers along with a feeble life for two or three years.
* * * * * Soil, whether of clay or sand, whether moist or dry, whether cultivated or in grass, manured or unmanured, does not appear to me, clearly, either to increase or diminish the liability to disease. Trees standing in exposed and sheltered situations, walled and in open ground, on hills and in valleys, seem alike and equally liable. * * * * * When the disease commences in a garden or orchard containing a considerable number of trees, it does not attack all at once. It breaks out in patches, which are progressively enlarged, till eventually all the trees become victims to the malady. * * * * * I took a blossom from a diseased tree, and applied the dust (pollen) to the blossom of a young tree in my garden. The tree thus exposed to infection, showed no mark of disease, either in that or the succeeding year.
I took some buds from a tree, having symptoms of the yellows, and inserted part into peach, part into apricot, and part into almond stocks. Some of the inoculations took well, but all showed marks of disease the next season. The peach and almond stocks, with their buds, died the second winter after inoculation. One apricot stock lived five years, but its peach top grew, in that time, to be only about three feet high.
'In an orchard or garden, containing both old and young trees, the young trees will generally be diseased first.
Peach-trees budded on apricots, plums, and sweet almonds, are liable to the yellows. * * Most of the applications for the cure of the disease, have been made on the supposition that it was caused by the peach-worm. Such are ashes, scalding water, charcoal, lime, salt, saltpetre, fish-oil, and urine. All of them have more or less agency in excluding the borer, but are not all effectual, even for that purpose. Some of them have seemed to promote, for a time, the growth of the trees, and to give a deeper green to their leaves; but none that I have ever observed, have at at all checked the progress of the yellows." The most effectnal, and the only remedy for this disease, hitherto discovered, is, on the first symptoms of decay, to grub up the trees by the roots, and convert them at once into fuel.
The principal other accidents to which the peach-tree is liable, are the splitting of the limbs at the forks by excessive weight, or by high winds, and the bursting of the buds and bark by severe frosts in open and wet winters.
Properties and Uses. The wood of the peach-tree is hard, compact, of a roseate hue, and is susceptible of a fine polish; but owing to its inferior size and comparative scarcity, it is but little used in the arts, or for fuel, except in countries where other kinds of wood are rare. When obtained, however, of suitable dimensions, it may be employed for similar purposes as that of the almond. A colour may also be extracted from it called rose-pink. Its leaves yield, by distillation, a volatile oil, of a yellow colour, containing hydrocyanic acid. Its bark, blossoms, and kernels of the fruit, also possess the same poisonous property. From the quantity of gum and sugar contained in the delicious pulp, the peach is nutritious, and is employed as a desert, both fresh and preserved. From the malic acid contained in its juice, it is slightly refrigerant, and if eaten in moderate quantities, it is generally considered as wholesome; but if taken too freely, it is liable to disorder the bowels. When stewed with sugar, it may be given as a mild laxative to convalescents. The kernels may be used for the same purpose as those of the bitter almond. The leaves are sometimes employed by the cook, the liquorist, and the confectioner, for flavouring, and they have also been substituted for Chinese tea; but, as fatal consequences have sometimes followed these uses, they should be looked upon with precaution.
The preservation of peaches, plums, cherries, apricots, and other kinds of fruit, in syrup, occupy a prominent rank in the industry and commerce of France and
of Majorca, and doubtless could be profitably carried on in those parts of the United States where these fruits are cultivated in abundance. To those who are desirous of entering into the business on an extensive scale, we would recommend the “ Nouveau Manuel du Limonadier, du Glacier, du Chocolatier, et du Confiseur," par MM. Cardelli, Lionnet-Clémandot, et Julia de Fontenelle, published at Paris in 1838; or, what would be still better, the employment of an intelligent confiseur who is practically acquainted with all its manipulations.
As an ornamental tree or shrub, the peach, and several of its varieties, are highly deserving of culture, and group well with the double-flowered cherry, the apple, and with the plum.