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American Pomology Part 7

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DIGGING THE TREES, is a process that should be conducted upon very different principles from those exercised in grubbing a thicket. The nurseryman wishes to clear his block, but the purchaser hopes to save his trees, and to have them live, he wants a good share of their roots with them. No one need expect, however, to have anything like a large proportion of the roots of a tree removed from the ground; that is out of the question, unless they have been grown in walled stations, confining the roots, like those of green-house plants in their flowerpots. In open culture, they will have spread through the soil in every direction, and cannot be preserved and removed. Repeated root pruning will be of the greatest service in furnis.h.i.+ng a great many fine roots within reach; but at the best, a great deal of damage is necessarily inflicted upon the roots by digging, and the older and larger the tree, the greater will be the injury, and the smaller the proportion of roots to the branches.

In digging trees, it is important to remove the soil very carefully on each side of the row to expose the roots, always holding the spade in such a position that its side and edge shall be in the direction of a radius, from the stem of the tree as a centre. Never stand facing the tree to be dug, but keep it next the elbow, at one side. On finding a root, withdraw the spade, and try again; and, having ascertained its direction, endeavor to loosen the outer extremities first. Proceed all around in this manner, and by gently swaying the trunk, the points of resistance will be indicated; these should be loosened and freed until all appear to be free, when, by grasping the collar as low down as possible, the tree is to be lifted gently and freed from the soil; no force should be used beyond that which is absolutely necessary, to lift the plant from its bed.

[Ill.u.s.tration: Fig. 23.--HARKNESS' TREE DIGGER.]

In the great commercial nurseries, all this care cannot be exercised; everything must be done in the large way, and labor-saving appliances, the valuable results of human thought, but still not thinking nor observing intelligences, must be used. One of this cla.s.s is the tree-digger, which, in the prairie soils, is used with very good success. It consists of a very large deep plow, without any mold-board, but with a wide sharp steel share, which is turned up at the edges, so as to cut the lateral roots at some distance from the trees. It is drawn on each side of the row, by four horses, hitched _ad tandem_. The trees may then easily be lifted from the loose prairie soil. The accompanying engraving shows the tree digger of Mr.

E. Harkness, which is much used in the nurseries of Illinois and other Western States. The figure is sufficiently clear, without much explanation. The broad steel blade runs under the rows and is drawn by four horses, two working one before the other, or _tandem_, each side of the row. Some of our Western nurserymen find great advantage from the use of this digger in their free soils, and also for root pruning trees that are to remain in the rows.

In the sandy loams of New Jersey, a similar tool is used for digging peach trees, which is drawn by a span of heavy horses that are attached to the two separate beams, one being on each side of the trees. This implement is found to be entirely satisfactory in its operations.

High manuring in the nursery has been objected to by some orchard planters, who say that trees, which have been forced into a too luxuriant growth in their infancy, receive so severe a shock upon being transplanted to the open field, that they never recover. With the neglect which is so commonly accorded to young trees in the orchard, it is really wonderful how they ever survive at all, whether they had been stimulated in their culture or not. The large majority of purchasers at the nursery always select those trees which are most vigorous, notwithstanding the prejudice against stimulating the trees, and then with mutilated roots, they probably omit cutting back the limbs sufficiently, and when their neglected orchard fails, they complain of the forced trees. The change from the good cultivation of the nursery to the careless culture and even neglect of the farm, is certainly hard for the poor things to bear. Late growth, encouraged by high manuring, is injurious. There is a much more serious fault of the nursery than stimulating with manure and high cultivation, and that is the too common error of crowding the trees; but even this has its origin partly with the purchaser, who too often wishes to have his trees drawn up as high as possible; instead of demanding low heads he asks for high ones, and will sometimes offer a premium for trees that have grown in one season, the second from the root graft, eight or ten feet in a single shoot, so that he may at once calculate upon forming the head where he wants it, out of the reach of his horse; a calculation, however, which he will not realize.

THE PREPARATION OF THE SOIL for a nursery should be as deep and as thorough as possible, for some things it is best even to trench the ground; but generally, the thorough plowing, with a deep-tiller, or a trench-plow, will be sufficient, and if followed by the subsoil lifter, so much the better. One of the most intelligent horticulturists, and most successful nurserymen in the country, finds that he can produce a better result in depth and fineness of tilth, by using the Double Michigan plow, than he can with the spade. A piece of clover-sod thus plowed in the fall, and subsoiled at the same time, will be in fine order for nursery purposes, after a thorough cross-plowing and harrowing in the following spring. If the land has been under-drained, so much the better. There is little good land that would not be much improved for nursery purposes by tile draining.

If manure is to be applied, it may be spread upon the clover-sod before plowing, or it may be thrown upon the plowed ground at once or at any time during the winter, to be worked into the soil by the spring plowing; if composted, it may be spread just before the spring stirring.

LAYING OUT.--In laying out the nursery, some taste may be exercised by the planter; the sections and blocks should be distinct, and alleys should be located at convenient distances, so that all parts may be easily accessible with the wagon. The rows should be laid out straight, and they ought to be far enough apart--four feet might be a good average for nursery trees; cuttings and seedlings may, of course, be nearer. The trees should not be set too closely in the rows, one foot apart is plenty close enough for most kinds, and that is little enough room for the development of good lateral branches, or for those which have to remain three or four years before transplanting. For peaches, for dwarf pears, and indeed for any of the varieties that are to be taken from the nursery as maiden trees, a less s.p.a.ce may be allowed--say eight inches apart. Apple stocks for budding, or for collar grafting, may be set ten inches apart, and they will have room to make very good plants, even should they remain until two years old.

Most nurserymen set out their apple grafts in the rows where they are to be grown to full size, and cultivate them from two to three years; while this saves the trouble of transplanting, the trees will not be as well a.s.sorted for size, nor will they have the benefit of the transplanting, (which will enhance their value much more than it costs, in the improved character of their roots), as have those that have been treated on the bedding plan, practiced by some nurserymen.

This consists in setting the root grafts closely together, in a bed of very well prepared ground; they are covered at once with a good mulching of sawdust, which keeps the ground moist, and insures the growth of almost all the plants, while for the first season they occupy very little s.p.a.ce, and are readily kept clean, as the mulching prevents the growth of weeds. In the fall, or in the following spring, they are taken up, a.s.sorted for size, and re-planted in the nursery-rows where they are to stand. This transplanting improves the character of their roots, which are more fibrous and shorter than in those trees which have stood three or four years without being disturbed. Purchasers, now-a-days, begin to look at the roots of their trees, as well as the tops; and it may become necessary for the nurserymen to gratify this fancy for low-headed, stocky trees, that have abundant fibres to insure their growth, and their early fruitfulness.

CULTURE of the nursery should be thorough; the soil should be frequently stirred, and kept mellow and loose, to insure cleanliness and thriftiness, and to make handsome trees. The mellow soil upon the surface, is, by some persons, considered equal to a good mulching, and indeed it answers the indications of one. Cultivation, to kill the weeds as fast as they appear, will admit both air and moisture; a share of both of these is retained by the mellow earth, which, thus treated, is indeed a very good mulch. The cultivation may be done with the small turning plow, with the double shovel, or with any of the many approved cultivators in use everywhere throughout the country.

The surface should be kept as level and even as possible. In some soils the roller, made short enough to pa.s.s between the rows, is highly esteemed, and is considered a most valuable implement in the nursery. As a general rule, cultivation should not be continued too late in the season, but should be suspended about mid-summer, so as to prevent a late growth and to encourage the plants to finish their summer's work in time to ripen their wood thoroughly before the advent of winter. This is particularly necessary where the climate is severe, especially on new lands, where the trees are very vigorous. Upon the approach of winter, it is a good practice to plow a light furrow against the trees on each side; this protects the collar from cold, prevents heaving by the frost, and gives a good surface drainage to excess of water.

For deeply loosening the ground between the rows, the one-horse subsoil lifting plow is a very valuable instrument; this can be used in very narrow s.p.a.ces. This plow prepares the ground admirably for the p.r.o.nged hoe, and it may be used between rows of cuttings and seedlings.

THE p.r.o.nGED HOE.--One of the most valuable implements in the nursery to clean out the weeds from between the trees, and also to work among cuttings, and other plants, that are set too closely for the use of the horse, is the p.r.o.nged hoe; it makes the best shallow culture, prevents the soil from becoming hard, and it is the best destroyer of small weeds that can be used. The flat hoe is never sharp enough to cut all of the weeds effectually, it produces little tilth, and the result of its use is too often a disappointment, but half killing the weeds, in some places, and dragging them out by the roots in others, and often leaving the ground hard and in miserable condition.

[Ill.u.s.tration: Fig. 24.--THE p.r.o.nGED HOE.]

PLANTING CUTTINGS.--Some of the small fruits, as currants, gooseberries, as well as the quince, are propagated, to a great extent, by cuttings. The ground for growing them, should be very well prepared by trenching or trench-plowing; the difference in the growth between cuttings set on well or on poorly prepared ground is astonis.h.i.+ng, and the advantage in favor of trenched land is sufficient to pay for the extra expense bestowed upon the preparation. The soil should be rather sandy, decidedly loose and mellow, and rather moist than dry.

In setting the cuttings, the rows may be quite close, as horse labor is seldom employed among them; but they are tended by hand, or the ground is mulched. They may also be set quite thickly in the row, as they are to remain but a short time in the cutting bed, from which they are transplanted at one year old, though sometimes alternate rows may be left over another season. When the trench is opened for them, the cuttings are set, three or four inches apart, next the line, so that only the top bud shall reach the surface; a little mellow soil is thrown upon them, and they are tramped firmly at the base, when the remainder of the earth is thrown in and the next trench is opened for another row. If they be planted in the autumn, it is well to cover them with a mulch, and for this leaves from the forest are an excellent material. Some propagators insist very strongly upon the necessity for removing all the buds from the lower portion of the cutting, particularly in the currant and gooseberry, so as to prevent suckering and to grow the bush as a miniature tree, with a single stem. This is not desirable when the bushes are liable to have the stems destroyed by the currant borer. Indeed, the nature of the currant appears to require a renewal of the wood by these shoots, which come to replace the old exhausted branches.

The grape is grown in immense quant.i.ties from cuttings, which are either planted in a nursery, or set at once in the vineyard. In the former they are planted closely in rows, that are about twenty inches apart. Sometimes the ground is trenched, and the cuttings set at the same operation. When the first trench is opened in a rich mellow loam, which may be sod or clover lea, the edge of the dug soil is dressed to the line with the spade, then the cuttings are placed so as to have one eye at or above the surface, and soil is thrown in and tramped closely to the base of the cuttings. Then the next trench is made with the spade, digging the ground as you proceed.

Grape cuttings are generally made eighteen or twenty inches long; and those which have a heel of old wood are preferred, and command a higher price. The earlier these are taken from the vines, after the fall of the leaves, the better success will attend the plantation; provided they are not too long exposed to the air. Fall planting is very desirable, but if not then planted, the cuttings should be put into the ground and covered as soon as convenient, and they will be better prepared for spring planting. A deep trench is opened, into which the bundles are set in a vertical position, and loose earth filled in about them, and slightly covered over them; they will then be ready for planting by the spring. The length of the cuttings has latterly been much reduced, with advantage; some of the most successful planters make them from six to eight inches long: these are much more easily dug than the longer slips, and are better provided with roots.

Tr.i.m.m.i.n.g should be practiced in the nursery with a definite object in view, and not at random; much less with any expectation of increasing the hight of the trees by tr.i.m.m.i.n.g them up. The object in pruning nursery trees should be to develop them in every part, to produce a stout stocky st.u.r.dy little tree, one that may be turned out upon the bleak prairie, and be able to withstand the blasts. To produce this result, the leaves should never be stripped from the shoots to make them extend their growth, for the sake of making more leaves; the nurseryman should know the value of leaves, as const.i.tuting the great evaporating surface that plays a most important part in causing the ascent of the crude sap, and also in its elaboration after it has been taken up into the organization of the plant. Leaves should be carefully preserved, and in the tr.i.m.m.i.n.g, which is necessary, this should be borne in mind. To make vigorous, stocky trees, the side branches should be encouraged rather than pruned off. The tops may sometimes need to be pinched, to force out the laterals, and to encourage their growth; if two shoots start together as rivals, one of them should be topped or cut back, or twisted and broken, but not cut off at its origin, unless there be plenty of lateral branches or twigs to furnish the tree. When these become too long, they may be spurred-in, either in the fall and winter when cutting grafts, or in the summer, during the growing season. Whenever it becomes necessary to trim off any of these laterals, it is best to do it at mid-summer, as the healing of the wounds made at this period is very rapid.

Heading off the nursery trees is done to force them to branch out uniformly the second year, to form their heads at the right place; this is to be done toward spring, and is applicable especially to those varieties that are p.r.o.ne to make a single shoot the first year without branching, and which have not been pinched-in or headed during the previous summer to force out side branches. Cherries, plums, and pears, and some apples, are very apt to make this kind of growth. It should have been premised that all nursery trees ought to be grown to one main stem, or leader, from which all the branches arise, and to which they should all be made to contribute their quota of woody fibre. It has been a.s.serted that the wood of a tree, instead of being a cone, as its stem appears to be and is, it should be a column of nearly equal size from the bottom to the top; that is, the ma.s.s of all the branches taken together, should equal the diameter of the trunk at any point below. A well-grown stocky nursery tree, with its abundance of lateral branches approximates this idea; but the main stem of such an one is very perceptibly a cone, rapidly diminis.h.i.+ng in diameter from the collar upwards.

AGE OF TREES FOR PLANTING.--This depends so much upon the views of planters, that the nurseryman cannot always control the period at which he shall clear a block of trees. Peaches should always be removed at one year from the bud. Plums and dwarf pears will be ready to go off at two years from the bud or graft; so with apples and cherries. But many persons, purchasers and sellers, prefer larger trees, and they recommend that the trees should remain one, two, or even three years longer in the nursery. Others, a new school of planters, prefer to set out the maiden tree, in most of the species above named, except some very feebly growing varieties, that will scarcely have attained sufficient size to risk in the orchard. The nurseryman should beware of keeping his trees too long on his hands; they may become unprofitable stock, and are sure to require much more labor in the digging and handling. The purchaser is his own master, and his tastes and wishes must be consulted; if he wants large trees, by all means, let him be indulged; he will have to pay in proportion, he will have more wood for his money, more weight to carry, or more transportation to pay for, more labor in planting, and vastly increased risk of the life of his trees; but, let him be indulged with his five year old trees, while his neighbor, for a smaller sum invested, with less freight, less wood, less labor, and infinitely less risk, will plant his maiden trees, and five years hence will market more fruit.

The risk of transplanting large or old trees from the nursery, may be greatly diminished, and their value will be vastly enhanced, by judicious root pruning in the nursery-row. This may be done by digging, on either side, on alternate years, and cutting off the straggling roots, and particularly those that run deeply; this will be followed by the production of a mult.i.tude of fibrous roots that put the tree into a good condition for transplanting. In the great nurseries of the West, there is a peculiar plow, which is used for root pruning the nursery rows.

THE HOME NURSERY has been recommended by Mr. Field in his _Pear Culture_ as a means of enabling the orchardist to amuse himself, and to grow his trees in such style as he may prefer. He advises to select trees "of two or three years' growth, and prepare a piece of ground for the home nursery. For this a rich, deep, dry soil should be spaded and thoroughly pulverized to the depth of two feet, (trenched).

In it plant the trees in rows four feet distant, and three feet apart in the rows. Two hundred trees would thus occupy a s.p.a.ce fifty feet square. The roots having been carefully examined, and, as before mentioned, the laterals pruned to six or eight inches, are spread out horizontally, and gently covered with earth. It will be seen that the labor of pinching, pruning, and cultivating, will be much less on so small a spot, than when the cultivator is obliged to travel over three or four acres upon which they are ultimately to be planted.

"If at the end of two years it is still desirable to allow them to remain, a sharp spade should be thrust down around them, at a distance of fifteen or eighteen inches, in order to cut the long straggling roots, and thus induce the formation of fibres nearer home. This will fit them for transplanting at an advanced stage of growth. In this case, if at the end of two or three years, they are removed at the proper season, and with care, they will suffer scarcely any check. By pursuing this plan, they receive better care, grow faster, and are not liable to damage; and as only the good trees will, in this case, be set in the fruit grounds, none of those unseemly breaks in the rows, caused by the injury or death of a tree, need occur. Where, however, older trees, at least once transplanted, cannot be obtained, and it is desirable to set out the orchard at once, stout two-year old trees are decidedly preferable. Such trees have not stood sufficiently long to send their roots beyond a limit whence they can be removed; and with careful digging, removal and planting, the purchaser need not fear a loss of more than two per cent."

THE NURSERY ORCHARD, as practiced by A.R. Whitney, of Lee Co., Ill., now one of the largest orchardists of the country, is well worthy of imitation by all those nurserymen, who desire also to become fruit-growers. In laying off the blocks of nursery stock, the varieties that are wanted for the orchard, should be planted in such a manner, that they shall be in every fourth row, so that the orchard trees will stand in rows sixteen to twenty feet apart, according as the nursery-rows are four or five feet wide. In cultivating and tr.i.m.m.i.n.g these rows in the nursery, a plant is selected, every twelve or sixteen feet, which is to remain as the orchard tree when the block shall be cleared. A good tree is selected, and special care in the pruning is bestowed upon it to secure the desired form, and low branches; if necessary, the tree on either side of it is removed, to give it room. By the time the block is cleared, these orchard trees are often in bearing, and while his customers are struggling to save their trees, and nursing them after their transplanting, the nurseryman will have become an orchardist, and is enjoying his fruits.

The nursery will have become an orchard--one rather closely planted to be sure--but the trees can be dwarfed by root pruning with the plow, they shelter one another from the prairie blasts, and when too thick, alternate trees may be removed to the wood-pile, and thus cheer the owner on a winter's day.

WINTER-KILLING is a serious evil in the nursery, as by it whole rows and blocks of certain varieties are sometimes destroyed, or very seriously injured. It has been observed to be most marked in its effects upon those sorts of trees that make the most vigorous and sappy growth, and those which continue to grow late in the season.

Such varieties have very naturally acquired the epithet of _tender_ especially as orchard trees of the same kinds, even in a bearing state, have been similarly affected; in some sections of the country, these kinds have been thrown out of cultivation. The bark looks shriveled and withered, the twigs seem dry when cut, and resist the knife; when thawed by the fire, or on the return of spring weather, the bark seems loose, and the inner bark, instead of being greenish-white, becomes brown, and the whole tree looks as though it was dead. In old trees, large portions of the bark start from the stem and large limbs, and hang loosely for awhile and then fall off. The buds alone retain their vitality, and upon the return of spring they sometimes succeed in establis.h.i.+ng the necessary connection with the soil, and restore the circulation of the sap; the results are the deposit of the usual annular layer of woody matter, which encases the dead portions within, that become like a _sequestrum_ of dead bone in an animal. The best treatment for the trees that have been winter-killed, is to cut them back very severely, in the hope of producing a vigorous wood-growth the next season, to repair the injury.

A partial winter-killing often affects small nursery trees, especially on low and wet, undrained soils; the plants recover, but for years they have a black point in the heart which embraces all of the wood-growth that was affected--all their wood at the period of the disaster. This is enclosed and surrounded by clear, healthy wood; but such trees are not desirable, they are so fragile, as to be easily broken.

The best preventive for winter-killing in the nursery, is to encourage early ripening of the wood, and to drain the land, is one of the best means of producing this effect; another is the cessation of culture at mid-summer, and the sowing of oats very thick at the last cultivation, has been practiced, and, it is thought, with excellent effects. The rank growth absorbs the superfluous moisture, robbing the trees, and afterwards forms a good protective mulch during the winter.

The objections to it are, that it encourages the mice, which, by girdling the trees, effectually winter-kills them.

Many nursery and orchard trees often present a black discoloration of the bark, which is quite unsightly, and excites alarm for the health of the tree. This is often caused by tr.i.m.m.i.n.g at unfavorable periods; in the spring pruning of bearing trees, the large stumps sometimes bleed, but in the nursery trees it arises from cutting them, and especially in the barbarous tr.i.m.m.i.n.g up, during severely cold weather, when they are frozen.

INJURIOUS ANIMALS AND INSECTS.--The nurseryman sometimes suffers from the depredations of some of the smaller animals, which cause him great annoyance. The mole, though highly recommended by the naturalists as a harmless beast, who is an aid to horticulture by his insectivorous habits, is nevertheless injurious in his _ways_; for he often makes his run in the seed bed, or along a row of root grafts, and raising them from their stations break their tender rootlets, when the sun and air soon destroy them. Mice, of different kinds, are still more destructive, particularly in the winter, when they will often girdle young trees near the collar, and do much mischief. They also devour many seeds after they have been committed to the ground, particularly those sown in the autumn. For both of these animals, the best preventive is to catch them, which may be done with traps. They may also be poisoned. The young trees may be protected from the mice by keeping them clear of rubbish, that would shelter these animals, and when snow falls, it should be trodden down closely about the trees.

Owls and cats will do their share in the destruction also, but they will also take the friendly little birds.

Rabbits are also very apt to bite off young shoots, and to bark trees of larger growth in the nursery, as well as those that have been set out in the orchard. Various methods have been suggested to prevent their injuries. Wrapping the stems with strips of rags or with ropes of hay, was formerly the method practiced by those who wished to save their young trees; the process is tedious and troublesome. A few pieces of corn-stalk have been placed by the stem of the tree and tied to it; this, too, is a troublesome procedure, though, like the others, it is efficacious. A still better plan in this cla.s.s of preventives, is a half sheet of common brown wrapping paper, made to encircle the stem, like an inverted funnel; this need be fastened only at the top, by a little thin grafting wax applied with a brush at the instant, or the paper may be tied with some common white cotton string. This envelope keeps off the rabbits, and lasts through the winter; the string will decay before the growing season returns, so there is no danger of strangulation. All the other wrappings must be removed, or they will injure the trees and afford harbor for insects. It will be observed that all applications of this cla.s.s, are adapted only to trees that have a clean hole without branches, but are not suited for those which are made to branch at or near the ground. Besides, in countries where snow abounds, these little marauders are elevated above the wrappings, and have fair play at the unprotected parts of the tree--on this account another cla.s.s of preventives has been adopted.

These consist in applications that are obnoxious to rabbits, which, being nice feeders, are easily disgusted. White-wash, and white-wash made with tobacco water, soap, whale-oil soap, grease, blood, and especially the dead rabbit itself, freshly killed, have all been used with happy results, in that they have driven these animals to seek their food elsewhere. A very good application, and one that may be used upon a low-branched tree as well as to the smooth clear stem of one that is higher, is blood. This is put on with a swab; a few corn husks tied to a stick, answers very well. Dipping this into the vessel of blood, the swab is struck gently against the stem or the branches, as the case may be, and the fluid is spattered over it. A very little will answer to keep the rabbits away, and the effect will continue all winter, notwithstanding the rains.

Certain insects also prove injurious in the nursery, among these the most numerous are the _aphides_, which are found upon the roots of some fruit trees, especially the apple. Others of this disagreeable insect appear upon the foliage, among these one of the most disgusting is the one which causes the black curl, on young cherry trees. The pear tree slug, (_Selandria cerasi_), destroys the foliage of many young trees in the nursery; caterpillars also do their share of mischief. A serious trouble in old nursery grounds, especially where manure is used, is the grub of the May beetles, of which there are several species. These grubs are whitish, nearly as thick as the little finger, with a brownish head. They cut off the young nursery trees at three or four inches below the surface. We have seen two-year old stocks cut in this manner, and the work of destruction was so complete, that the proprietor of the nursery was a long time in attributing it to such an apparently inadequate cause as this sluggish, soft-bodied grub. All of these, with other insects injurious to fruit, will be considered in their appropriate place.

FOOTNOTES:

[12] The Plant, a Biography: M.J. Schleiden, p. 68.

[13] Because it had no root, it withered away. Mat. 13, 6.

[14] Du Breuil, Culture of Fruit Trees; English Translation.

[15] A.R. Whitney, Franklin Grove Nurseries, Lee Co., Ill.

CHAPTER IV.

DWARFING.

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