"It will usually be necessary to tie the grafts. A well-made cleft graft often holds the scion with sufficient force to prevent its displacement and no tying is necessary. Wherever there is any danger of the graft moving, however, it should be tied. There is nothing better for this purpose than ordinary raffia. The raffia should not be bluestoned, as it will last long enough without and will be sure to rot in a few weeks, and the trouble of cutting it will be avoided. Cotton string or anything which will keep the graft in place for a few weeks may also be used.
"As soon as the graft is made and tied, a stake should be driven and the union covered with a little earth. The hilling up of the graft may be left for a few hours, except in very hot, dry weather. Finally, the whole graft should be covered with a broad hill of loose soil 2 inches above the top of the scion.
"Field grafting should not be commenced as a rule, except in the hottest and driest localities, before the middle of March. Before that there is too much danger that heavy rains may keep the soil soaked for several weeks—a condition very unfavorable to the formation of good unions. In any case the grafting should not be done while the soil is wet. Grafting may continue as long as the cuttings can be kept dormant. It is difficult to graft successfully, however, when the bark of the stock becomes loose, as it does soon after the middle of April in most localities."
As in the East, it is necessary in California to remove suckers from the roots and roots from the cions once or twice during the summer. Suckers should not be allowed to overshade the graft, though it is best not to remove them until danger of disturbing the graft is past. The grafts should be staked and the vines looked after as recommended for eastern conditions.
The resistant vineyards of France and California are now started almost entirely with bench-grafted vines. It has been learned in these regions that a grafted vine, to be a permanent success, must have the consorting parts perfectly united, and that the sooner the grafting is done in the life of stock and cion the better the union. Cions of the variety wanted are, therefore, grafted on resistant roots or resistant cuttings in the workshop and then planted in the nursery. Bench grafting has the advantage over field grafting in time gained and in securing a fuller stand of vines.
Bench grafting really begins with the selection of cuttings, since success largely depends on good cuttings of both stock and cion. Cuttings are taken from strong healthy vines and are of medium size, with short to medium joints. The best size is one-third of an inch in diameter, that of stock and cion being the same since the two must match exactly. The cutting-wood may be taken from the mother vines at any time during the dormant season up to two weeks before buds swell in the spring, and the cuttings can then be made as convenience dictates, though meanwhile the wood must be kept cool and moist, which is best done by covering them with moist but not wet soil or sand in a cellar or cool shed. In California, the best results are obtained when the grafting is done in February or March, though it may be begun earlier and continued a month later.
Preparation of cuttings.
The stocks are cut into lengths of about ten inches, a gauge being used to secure uniform length. The cut at the bottom is made through a bud in such a way as to leave the diaphragm. The top cut is made as near ten inches from the bottom as possible, leaving about one and one-half inches above the top bud for convenience in grafting. The stock is then disbudded, taking both visible and adventitious buds, the latter indicated by woody enlargements, to keep down the number of suckers.
The cion should be made with but one bud, thereby gaining the advantage of having every cion the same length so that all unions are at the same distance below the surface of the ground in the nursery. The cion is made with about two and one-half inches of internode below the bud and one-half inch above, a sharp knife being the best tool for making the cuts.
Stock and cion cuttings are now graded to exactly the same diameters, this being necessary to secure perfection in the unions. Three methods of uniting stock and cion are illustrated in Fig. 12. It suffices to grade by the eye into three lots—large, small and medium—but some nurserymen prefer to secure even greater accuracy by the use of any one of several mechanical gauges. The methods of uniting stock and cion may be described best by quoting Bioletti, from whom most of the details already given have been summarized:
"When the stocks and scions are prepared and graded the grafter takes a box of stocks and a box of the corresponding size of scions and unites them. Each is cut at the same angle in such a way that when placed together the cut surface of one exactly fits and covers the whole of the cut surface of the other. The length of cut surface should be from three to four times the diameter of the cutting, the shorter cut for the larger sizes and the longer for the thinner. This will correspond to an angle of from 14.5 to 19.5 degrees. The cut should be made with a sliding movement of the knife. This will make the cut more easily and more smoothly.
"The cut should be made with a single quick motion of the knife. If the first cut is not satisfactory, a completely new one should be made. There should be no paring of the cut, as this will make an irregular or wavy surface and prevent the cuttings coming together closely in all parts.
"The tongues are made with a slow, sliding motion of the knife. They are commenced slightly above one-third of the distance from the sharp end of the bevel and cut down until the tongue is just a trifle more than one-third the length of the cut surface. The tongue should be cut, not split. The knife should not follow the grain of the wood, but should be slanted in such a way that the tongue will be about one-half as thick as it would be if made by splitting. Before withdrawing the knife it is bent over in order to open out the tongue. This very much facilitates the placing together of stock and scion.
"The stock and scion are now placed together and, if everything has been done properly, there will be no cut surface visible and the extremity of neither stock nor scion will project over the cut surface of the other. It is much better that the points should not quite reach the bottom of the cut surface than that they should overlap, as the union will be more complete and the scions will be less liable to throw out roots. If the points do overlap, the overlapping portion should be cut off, as in the Champin grafts.
"A skillful grafter, by following the above-described method, will make grafts most of which will hold together very firmly. Many of them would be displaced, however, in subsequent operations, so that it is necessary to tie them. This is done with raffia or waxed string. The only object of the tying is to keep the stock and scion together until they unite by the growth of their own tissues, so that the less material used the better, provided this object is attained. For the formation of healing tissue air is necessary, so that clay, wax, tinfoil or anything that would exclude the air should not be used. The tying material is passed twice around the point of the scion to hold it down firmly, and then with one or two wide spirals it is carried to the point of the stock, which is fastened firmly with two more turns and the end of the string passed under the last turn. The less string is used the more easily it is removed later in the nursery.
"Untreated raffia should be used for late grafts which are to be planted directly out in the nursery, but if the grafts are to be placed first in a callusing bed it is best to bluestone the raffia in order to prevent rotting before the grafts are planted. This is done by steeping the bundles of raffia in a three per cent solution of bluestone for a few hours and then hanging them up to dry. Before using, the raffia should be washed quickly in a stream of water in order to remove the bluestone which has crystallized on the outside and which might corrode the graft.
"Some grafters prefer waxed string for grafting. The string should be strong enough to hold the graft, but thin enough to be broken by hand. No. 18 knitting cotton is a good size. It is waxed by soaking the balls in melted grafting wax for several hours. The string will absorb the wax, and may then be placed on one side until needed. A good wax for this purpose is made by melting together one part of tallow, two parts of beeswax, and three parts of rosin."
"The merits claimed for this method are that it is more rapid, requires less skill, and does away with the troublesome tying and still more troublesome removal of the tying material. Practiced grafters can obtain as large a percentage of No. 1 unions by this method as by any other, and unpracticed grafters can do almost as well as practiced. Another advantage of the method is that the scions have less tendency to make roots than with the tongue graft.
"It consists essentially of the use of a short piece of galvanized iron wire inserted in the pith of stock and scion for the purpose of holding them together, thus replacing both tongues and raffia. It has been objected that the iron would have a deleterious effect on the tissues of the graft, corroding them, or causing them to decay. There seems, however, no reason to expect any such result, and vines grafted in this way have been bearing for years without showing any such effect.
"The preparation and grading of stocks and scions are exactly the same for this method as for the tongue graft.
"Stock and scion are cut at an angle of 45 degrees. A piece of galvanized iron wire two inches long is then pushed one inch into the firmest pith. This will usually be the pith of the stock, but it will depend on the varieties being grafted. The scion is then pushed on to the wire and pressed down until it is in contact with the stock. If the cuttings have large pith it is better to use two pieces of wire, one placed in the stock first and the other in the scion.
"The length of wire to use will vary with the size and firmness of the cuttings, but 2 inches will usually be found most satisfactory. Wire of No. 17 gauge is the most useful size."
"If the grafts are to be planted out directly in the nursery, they may be simply laid in boxes or trays, covered with damp sacks, and carried out to be planted as soon as made. It is usually better, however, to place them for several weeks in a callusing bed before planting. In this case it is necessary for convenience of handling to tie them up into bundles. No more than twenty grafts should be placed in a bundle, and ten is better. If the bundles are too large there is danger of the grafts in the middle becoming moldy or dry.
"A stand is very convenient. It consists of a piece of board 12 inches, on one end of which is nailed a cleat 6 inches by 4 inches and under the other end a support of the same size. Two 4-inch wire nails are driven through the board from below, 4 inches apart and 5 inches from the cleat. Two other 4-inch nails are driven similarly at 1-1/2 inches from the other end. The grafts are laid on this stand with the scions resting against the cleat, and are then tied with the two pieces of bluestoned raffia that have previously been placed above each pair of nails. This arrangement insures all the scions, and therefore the unions, being at the same level, and puts both ties below the union where they will not strain the graft. The tying is more expeditious and less liable to disturb the unions than if the bundles are made without a guide.
"A skillful grafter will make about one hundred tongue grafts on cuttings per hour, or from sixty-five to seventy-five per hour if he does the tying as well. Wire grafts can be made at the rate of two hundred and fifty or more per hour, and by proper division of labor where several grafters are employed this number can be easily exceeded. These estimates do not include the preparation and grading of the cuttings."
Grafting rooted cuttings.
The cion may be grafted on a stock rooted in the nursery the previous season, much the same methods being used as with cuttings. This method is employed to utilize cuttings too small to graft, the added sizes attained in the nursery making them large enough, and in grafting on stocks which root with difficulty, thus saving the making of grafts which never grow. The stocks, in this method, are cut so that the cions may be inserted as the original cutting and not as the new growth. The roots, for convenience in handling, are cut back to an inch or thereabouts in length.
The callusing bed.
If bench grafts are planted at once in the nursery, most of them fail. They are, therefore, stratified in a callusing bed where moisture and temperature can be controlled. Bioletti describes a callusing bed and its use as follows:
"This callusing bed is usually a pile of clean sand placed on the south side of a wall or building and surrounded by a board partition where there is no possibility of its becoming too wet by the flow of water from a higher level or from an overhanging roof. It should be protected, if necessary, by a surrounding ditch. It should be furnished with a removable cover of canvas or boards to protect it from rain and to enable the temperature to be controlled by the admission or exclusion of the sun's rays. A water-proof wagon-cover, black on one side and white on the other, is excellent for this purpose.
"The bottom of the callusing bed is first covered with 2 or 3 inches of sand. The bundles of grafts are then placed in a row along one end of the bed, and sand well filled in around them. The bundles should be placed in a slightly inclined position with the scions uppermost, and the sand should be dry enough so that it sifts in between the grafts in the bundle. The bundles of grafts are then covered up completely with sand, leaving it at least 2 inches deep above the top of the scion. Another row is then placed in the same manner until the bed is full. Finally a layer of 2 or 3 inches of moss or straw is placed over all.
"In the callusing bed we should endeavor to hasten and perfect the union of stock and scion as much as possible while delaying the starting of the buds and the emission of the roots. The latter processes require more moisture than the formation of healing tissue, therefore the sand should be kept comparatively dry. Between 5 and 10 per cent of water in the sand is sufficient. The purer the sand the less water is necessary. There should be a little more moisture present than in the sand used for keeping the cuttings over winter. Too much moisture will stimulate the emission of roots and starting of buds without aiding the callus formation.
"All the vital processes progress more rapidly when the cuttings are kept warm. To delay them, therefore, we keep the sand cool, and to hasten them we make it warm. In the beginning of the season and up to the middle of March we keep the sand cool. This is done by keeping the bed covered during the day when the sun is shining, and uncovering occasionally at night when there is no fear of rain. If the black-and-white wagon-cover is used, the white side should be placed outward to reflect the heat. The temperature should be kept about 60 deg. F. or lower.
"About the middle of March the temperature of the bed should be raised. This is done by removing the cover during warm days and carefully covering at night. If necessary the layer of moss or straw should be removed on sunny days and then replaced. The temperature of the sand at the level of the unions should be about 75 deg. F. during this period. If the temperature rises higher than this, there will be a more abundant production of callus, but it will be soft, easily injured, and liable to decay.
"At the end of four weeks after warming the bed, the union should be well cemented. The callus should not only have formed copiously around the whole circumference of the wound, but it should have acquired a certain amount of toughness due to the formation of fibrous tissue. It should require a pull of several pounds to break the callus and separate stock and scion. When the callus has acquired this quality the grafts are in condition to be planted in the nursery, and may be handled without danger. If taken from the bed while the callus is still soft, many unions will be injured and the grafts will fail, or unite only on one side.
"If left as long as this in the callusing bed most of the scion buds will have started and formed white shoots. These shoots, however, should not be more than 1/2 to 1 inch long. If they are longer the bed has been kept too wet or too warm. Roots will also have started from the stock, but these also should not be over 1/2 inch long. The grafts should be handled as carefully as is practicable, but there is no objection to breaking off any scion shoots or stock roots which have grown too long. It is almost impossible to save them, and new ones will start after the grafts are planted, and make a perfectly satisfactory growth."
Care in the nursery.
The grafts are planted in the nursery, and are given much the same care recommended for cuttings. They may be set in trenches made with plow or spade; or they may be planted in very shallow trenches with a dibble. After planting, the grafts are covered with an inch or two of soil, thus forming a wide ridge in the nursery row with the union of the grafts at the original level of the soil. Cultivation should begin at once and be frequent enough to prevent the formation of a crust, in order that the young shoots may not have difficulty in forcing their way through the soil. Roots start on the cions sooner than on the stock, the soil being warmer at the surface, and help sustain the cions until the stocks are well rooted, at which time all roots started on the cion are removed, and at the same time the tying material is cut if it has not rotted. Suckers are removed as soon as they show above ground. The grafts are dug as soon as the leaves fall and the young vines become dormant, after which they are sorted in three lots, according to size of top and root, and heeled-in in a cool moist place until they are to be planted.
Nursery versus home-grown vines.
The verdict of all vineyardists is that it is better to buy nursery-grown vines than to attempt to grow them. The high quality of the vines which can be purchased and the reasonable purchase price make it hardly worth while to try home-grown vines, especially since considerable investment, experience and skill are required to grow good vines.
"PEDIGREED" GRAPE VINES
Many viticulturists, in common with orchardists, believe that their plants should be propagated only from parents which have good characters, that is, are vigorous, healthy, productive, and bear fruit of large size, perfect form, good color and good quality. They believe, in short, that varieties can be improved by bud selection. There is, however, but little in either theory or fact to substantiate the belief of those who say that varieties once established can be improved; or, on the other hand, that they degenerate. Present knowledge and experience indicate that heredity is all but complete in varieties propagated from parts of plants. The multitude of grapes in any variety, all from one seed, are morphologically one individual. A few kinds of grapes go back to Christ's time, and these seem to agree almost perfectly with the descriptions of them made by Roman writers 2000 years ago. How, then, can the differences between vines of a variety in every vineyard in the land be explained?
Ample explanation is found in "nurture" to account for the variation in vines without involving a change in "Nature." Soil, sunlight, moisture, insects, disease, plant-food, and the stock in the case of grafted vines, give every vine a distinct environment and hence a distinct individuality of its own. Peculiarities in a vine appear and disappear with the individual. A variety can be changed temporarily by its environment, but remove the incidental forces and it snaps back into its same old self.
Heredity is not quite complete in the grape, however; for, now and then, sports or mutations appear which are permanent and, if sufficiently different, become a strain of the parent variety or possibly a new variety. There are several such sports of the Concord under cultivation. The grape-grower can tell these sports from the modifications brought about by environment only by propagation. If a variation is transmitted unchanged through successive generations of the grape, as occasionally happens, it may be looked on as a new form. "Pedigreed" vines, then, should be subject to a test of several generations in an experimental vineyard before the grape-grower pays the price demanded for the supposed improvement.
STOCKS AND RESISTANT VINES
Phylloxera, a tiny root-louse, made its appearance in France in 1861 and began multiplying with a fury unparalleled in the insect world. By 1874, the pest had become so widespread in Europe that it threatened the very existence of the great vineyard industry of that continent. All attempts to bring the pest under control failed, although the French government offered a reward of 300,000 francs for a satisfactory remedy. Numerous methods of treating the soil to check the ravages of the insect were tried, also, but none was efficacious. Finally, it dawned on European vineyardists that phylloxera is not a scourge in America, its habitat, and that European vineyards might be saved by grafting Vinifera vines on the roots of immune American grapes. At once the reconstruction of vineyards in Europe was begun by grafting the grapes on phylloxera-resistant roots. Meanwhile, consternation spread to California when it was discovered that phylloxera was running riot in some of the vineyards of the Pacific slope; however, with the knowledge derived from viticulturists in Europe, they too began reconstructing vineyards on immune roots, without the same success as the Europeans, it is true, but with such measure of success that it soon became the approved method of growing grapes in this great region.
Through the use of resistant stocks, phylloxera is now defied in Vinifera regions. Millions of American stocks are annually struck at home, in Europe and wherever Vinifera grapes are grown, to be top-worked with varieties susceptible to phylloxera. Seldom has mastery over a pest been so complete; but, to triumph over the tiny insect, the industry has had to be revolutionized. Resistant stocks, in their turn, brought innumerable new problems, many of which are still unsolved. Investigations and experiences in rehabilitating vineyards have been carried on for forty years, the results set forth in books and bulletins and yet there are many problems to be solved. The grape-grower in regions infested with phylloxera is always under the necessity of taking advantage of the latest demonstration of practices in the use of resistant stocks. These practices are best studied in the experiments of state experiment stations and the United States Department of Agriculture, and in the vineyards of leading grape-growers, since even those most needing elucidation can be but briefly discussed in the following paragraphs.
The wild vines of a species are always seedlings and are hence exceedingly variable. The first vineyards of resistant stocks were vines grafted on stocks of wild vines, and the results were very unsatisfactory; for, naturally, there was divergence in many characters and especially in the vigor of the vines. Also, there was difficulty in grafting, since some wild vines are stout and others slender; some bear grafts well, while others do not. It soon became apparent that to succeed, varieties must be selected from the different species for vineyard work. The great task of the experimenter and grape-grower, therefore, has been to select varieties of the several species sufficiently resistant, vigorous and otherwise possessed of characters fitting them to become good stocks. Out of vast numbers tested, a few are now generally recognized as best for the several groups of Vinifera grapes and the several distinct regions in which these grapes are grown.
Resistant species and varieties.
The reconstruction of phylloxera-ridden vineyards by the use of resistant stocks is possible only because some species and varieties are, as has been said, more resistant to the root-louse than others. All degrees of resistance exist, as would be suspected, from immunity to great susceptibility. It is obvious that the foundation of the art of growing resistant vineyards is exact knowledge of the immunities and susceptibilities of the many varieties and species of grapes. From the first use of resistant vines, experimenters everywhere have set themselves at work to determine not only what the most resistant vines are, but what the causes and conditions of immunity. In spite of a wealth of empirical discoveries as to what grapes can best resist the root-louse, causes and most of the conditions of immunity are still little understood. Definite, useful knowledge, so far, goes little further than the establishment of lists of species and varieties, the latter subject to change, that are most useful in setting resistant vineyards.
Phylloxera does little damage to species of Vitis native to the same general region in which the pest has its habitat, but nevertheless there are some differences in resistance in American grapes. Munson, one of the best American authorities on the resistance of species to phylloxera, says: "Rotundifolia is entirely immune, then Rupestris, Vulpina, Cinerea, Berlandieri, Champini, Candicans, Doaniana, AEstivalis and Lincecumii are so high in resistance as to be practically uninjured, though they may be attacked, while Labrusca is low in resistance and is much weakened in clay soils, if infested, and Vinifera is entirely non-resistant." Some of these species are hard to propagate and difficult to suit in soil and climate so that but two of them are much used for resistant stocks. The two most used are Rupestris and Vulpina (Riparia), of both of which there are varieties which give satisfaction. Bioletti, a leading authority on resistant stocks in California, says:
"Varieties of resistant stocks which will in all probability be used in California are Rupestris St. George (du Lot), Riparia x Rupestris 3306, Riparia x Rupestris 3309, Riparia Solonis 1616, Mourvedre x Rupestris 1202, Aramon x Rupestris 2, Riparia gloire, and Riparia grande glabre. These are all varieties which have given excellent varieties for years in Europe, and have all been tested successfully in California. Among them are varieties suitable for nearly all the vineyard soils of California, with perhaps the exception of some of the heavier clays.
"The only one of these varieties which has been planted extensively in California is the Rupestris St. George. There can be little doubt, however, that it will fail to give satisfaction in many soils, and though we may not find something better for all our soils it is probable that we will repeat the experience of Southern France and find that in most soils there is some other variety that gives better results. Without attempting to describe these varieties, but to give some idea of their merits and defects and of the soils most suited to each, the following indications are given, based principally on the opinions of L. Ravaz and Prosper Gervais, and on a still limited experience in California:
"The Rupestris St. George is remarkably vigorous and grows very large, supporting the graft well even without stakes. It roots easily and makes excellent unions with most vinifera varieties. It is well suited to deep soils where its roots can penetrate. Its defects are that it is very subject to root-rot, especially in moist soils; it suckers badly and it suffers from drought in shallow soils. Its great vigor produces coulure with some varieties and often necessitates long pruning.
"In moist or wet soils 1616 or 3306 had given better results in France and gives indications of doing equally well here. In drier soils 3309 will probably be found preferable.
"Aramon Rupestris No. 2 is suited to the same soils as Rupestris St. George, and does particularly well in extremely gravelly soils. It has some of the defects of the St. George and is moreover more difficult to graft, and its only advantage in California is that it is rather less susceptible to root-rot.
"There are no better resistant stocks than Riparia gloire and Riparia grande glabre, wherever they are put in soils that suit them. They do well, however, only in deep, rich, alluvial soils which are neither too wet nor too dry. Their grafts are the most productive of all, and ripen their grapes from one to two weeks earlier than the grafts on St. George. Their principal defect is that they are very particular as to the soil, and they never grow quite as large as the cion. The gloire is the most vigorous, and the difference of diameter is less with this variety than with any other Riparia.
"The Mourvedre x Rupestris 1202 is extremely vigorous, roots and grafts easily, and is well adapted to rich, sandy and moist soils. In drier and poorer soils its resistance is perhaps not sufficient.
"The most promising varieties for general use at present seem to be the two hybrids of Riparia and Rupestris, 3306 and 3309. They have great resistance to the phylloxera, root and graft almost as easily as St. George, and are quite sufficiently vigorous to support any variety of vinifera. The former is more suited to the moister soils and wherever there is danger of root-rot, and the latter to the drier soils. In general, they are suited to a larger variety of soils and condition than perhaps any other varieties.
"Riparia gloire should be planted only on rich, deep alluvial soil containing an abundance of plant food and humus, what would be called good garden land, such as river bank soil not liable to overflow.
"In most other soils Riparia x Rupestris 3306 is to be recommended, except those that are rather dry, where 3309 is to be preferred, or those which are very wet, where Solonis x Riparia 1616 is surer to give good results."
The value of a species or variety for a resistant stock may be judged somewhat by the visible effect of the phylloxera on the roots of the vines. On susceptible species, the punctures of the insects rapidly produce swellings which vary in size and number in accordance with resistance of the species. Technically, the first swelling on the young tender rootlets of the vine is called a nodosity. The presence of a few nodosities on the root system does not indicate that a vine is not a valuable resistant stock. When the nodosity begins to decay and becomes of a cancerous nature, it is called a tuberosity. These tuberosities decay more or less rapidly and deeply, and when they rot deeply cause enfeeblement or death to the vine. Thus, on Vinifera varieties the tuberosities are several times larger and decay sets in much more quickly than on American species which show these tuberosities. Ratings as to resistance of species are usually made from the size and number of the tuberosities, though when these are found producing a scab-like wound which scales off, there may be high resisting power.
In order to convey with some degree of definiteness the power of resistance to phylloxera, an arbitrary scale has been agreed on by viticulturists. In this scale, maximum resistance is indicated by 20 and minimum by 0. Thus, the resisting power of a good Vulpina is put as 19.5 and that of a poor Vinifera variety as 0.
ADAPTATIONS OF RESISTANT STOCKS TO SOILS AND CLIMATES
Resistance, of course, counts for naught in a stock which comes from a species unsuited to the soil and climate or other circumstances of the locality in which the vineyard is to be planted. The several species used for stocks differ widely in the requirements affecting growth so that the grower must make certain that the resistant stock he selects will find congenial surroundings. Stocks in congenial circumstances are frequently more resistant than others inherently more resistant, but which are not otherwise adapted to the particular conditions of the vineyard. Species of grapes vary greatly in their root systems, some having thick, others slender roots; the roots of some are soft, of others hard; some have roots going down deeply, others are almost at the surface of the ground. Manifestly these various root-forms are but adaptations to loose and heavy, dry and moist, deep and shallow soils, or to some circumstance of climate. A vine bruised by adversity is in no condition to withstand phylloxera. Therefore, since the adaptability of a variety to a soil or climate may be changed by the stock, the adaptations of stocks to soils and climates must have attention.
Affinity of stock and cion.
Different varieties of grapes do not behave alike on the same stocks, and different stocks may affect varieties differently. Even when the kinship is close, some grapes resist all the appliances of art to make a successful union; while, on the other hand, quite distinct species often seem foreordained to be joined. For example, Rotundifolia, which has the highest resistance to phylloxera of any species, is useless as a stock because it is impossible to graft any other grape on it, while Vulpina and Rupestris unite readily with varieties of Vinifera, the slight decrease in the vigor of the grafted vines serving oftentimes to increase fruitfulness. Something more is necessary, then, than botanical kinship. Just what is necessary, no one knows, beyond: that there must be conformity in habit between stock and cion; that the two must start in growth at approximately the same time; and that the tissues must be sufficiently alike that there be proper contact in the union. Yet these facts do not sufficiently explain all of the affinities and antipathies which species and varieties of grapes show to each other. Unfortunately, the grape-grower has had but little to guide him in selecting stocks and has had to learn by making repeated trials.
PROPER PLANTING OF GRAFTED VINES
Europeans and Californians long ago learned that failures with grafted vines often came from setting the vines too deep in the soil, the result being that the cions struck root and became independent, whereupon the stock dies or becomes so moribund that the beneficial effects are lost. There are grape-growers who argue that it is beneficial to the vine to have roots from both stock and cion, but experience and experiments very generally teach the contrary, it being found that in most grafts the cion roots grow more vigorously than stock roots and eventually starve out the latter. The disastrous effects of cion-rooting are often to be found, also, when grafting has been done on old vines in the vineyard; and, again, when the graft is too close to the root system.
Another cause of failure is that different stocks require that the vineyard soil be treated differently, especially at planting time. Vulpina stocks require that the soil be much more deeply plowed than for Viniferas on their own roots, since Vulpinas are deep-rooted and are exacting in the depth of root-run required. Those who have had most experience with resistant stocks maintain that all American grapes require rather deeper plowing than European grapes on their own roots.
INFLUENCE OF THE STOCKS ON THE CION
Up to the present, the growing of grafted grapes has been carried on with little thought of the mutual influence of stock and cion; grapes have been grafted only to secure vines resistant to phylloxera. Yet there can be no doubt that stock and cion react on one another, and that any variety of grapes is influenced for better or worse in characters of vine and fruit by the stock upon which it is grafted. A plant is a delicate mechanism, easily thrown out of gear, and all plants, the grape not the least, are more or less changed in the adjustments of stock and cion. One could fill a large volume on the supposed reciprocal influence of stock and cion in fruits. Space suffices, here, however, to mention only those proved and those having to do with the influence of the stock on the cion when the grape is grafted.
Influence of stocks on European grapes summarized.
Common experience in Europe and California indicates that varieties of Vinifera grapes grafted on resistant stocks which are perfectly adapted to soil and climate produce not only larger crops but sweeter or sourer grapes; that the crop ripens earlier or later; that the vine is often more vigorous; and that there are some minor differences depending on the stock used. Wine-makers assert that the character of their product may be affected for better or worse by the stock. Often vines are so improved by grafting that the extra expense of the operation and of the stock is paid for; although, to be sure, about as often the effects are deleterious. The successes and failures of vineyards on resistant stocks make plain that the vine-grower must study the many problems which stocks present and exercise utmost intelligence in the selection of the proper stock.
Influence of stocks on American grapes.
No doubt American species of grapes may be as profoundly modified by stocks as the European species, but there is but little evidence on this phase of grape-growing to be drawn from the experience of vineyardists. One rather conclusive experiment, however, shows that American grapes may be improved by growing them on stocks which give them better adaptations to their environment. The experiment was tried in the Chautauqua grape-belt in western New York by the New York Agricultural Experiment Station. The test was carried on for eleven years, during which time many interesting possibilities in grafting grapes in this region came to light. It was proved that the stock materially affects the vigor and productiveness of the vine and the quality of the grapes. The following brief account is taken from Bulletin No. 355 of the New York Station:
In this experiment a number of varieties were grafted on St. George, Riparia Gloire and Clevener stocks, and a fourth group on their own roots. The varieties grafted were: Agawam, Barry, Brighton, Brilliant, Campbell Early, Catawba, Concord, Delaware, Goff, Herbert, Iona, Jefferson, Lindley, Mills, Niagara, Regal, Vergennes, Winchell and Worden. The planting plan and all of the vineyard operations were those common in commercial vineyards.
Yearly accounts of the vineyard show that the vines passed through many vicissitudes. The experiment was started in 1902 when St. George and Riparia Gloire stocks from California were set and grafted in the field. Many of these died the first year. The winter of 1903-04 was unusually severe, and many more vines were either killed or so severely injured that they died during the next two years. The vines on St. George, a very deep-rooting grape, withstood the cold best. Fidia, the grape root-worm, was found in the vineyards early in the life of the vines and did much damage in some years. In the years of 1907 and 1909 the crops were ruined by hail.
But despite these serious setbacks it was evident throughout the experiment that the grafted grapes made better vines and were more productive than those on their own roots. As an example of the differences in yield, a summary of the data for 1911 may be given. In this year, an average of all the varieties on own roots yielded at the rate of 4.39 tons to the acre; on St. George, 5.36 tons; on Gloire, 5.32 tons; on Clevener, 5.62 tons. The crops on the grafted vines were increased through the setting of more bunches and the development of larger bunches and berries.
The grapes on the vines grafted on Gloire and Clevener ripened a few days earlier than those on their own roots, while with St. George a few varieties were retarded in ripening. Changing the time of maturity may be very important in grape regions where there is danger of early frost to late-ripening sorts, and where it is often desirable to retard the harvest time of early grapes.
In the behavior of the vines, the results correspond closely with those given for yields. In the growth ratings of varieties on different stocks, the varieties on their own roots were rated in vigor at 40; on St. George, at 63.2; on Gloire, at 65.2; on Clevener, at 67.9. There is no way of deciding how much the thrift of the vines depends on adaptability to soil, and how much on other factors. Since all of the varieties were more productive and vigorous on grafted vines than on their own roots it may be said that a high degree of congeniality exists between the stocks and varieties under test.
The experiment suggests that it would be profitable to grow fancy grapes of American species on grafted vines, and that it is well within the bounds of possibility that main-crop grapes can be grafted profitably. In the general tuning-up of agriculture now in progress, it may be expected that soon American as well as European varieties of grapes will be grown under some conditions and for some purposes on roots other than their own.
Attempts innumerable have been and are still being made to secure, by hybridizing V. vinifera and American species of grapes, varieties that will resist phylloxera, the mildew and black-rot. The grapes of this continent are relatively immune to all of these troubles, and if hybrids could be obtained to produce directly, without grafting, grapes with the good qualities of the Viniferas—in short, European grapes on American vines—the cultivated grape flora of the whole world might be changed. So far, a "direct producer" that is wholly satisfactory in either Europe or California has not been found for the wine or raisin industries, although a number of varieties are rated as very good table grapes, and a few are used in wine-making. The best of the direct producers are Lenoir, Taylor, Noah, Norton's Virginia, Autuchon, Othello, Catawba, and Delaware.
THE VINEYARD AND ITS MANAGEMENT
A vineyard is more artificial than other plantations of fruits, since the vine requires greater discipline under cultivation than tree or bush. Yet greater art is required only when the attempt is made to grow the grape to perfection, for the vine bears fruit if left to indulge in riotous growth wheresoever it can strike root. Vineyard management, therefore, may represent the consummate art of three thousand or more years of cultural subserviency; or it may be so primeval in simplicity as to approach neglect. The grape is so wonderfully responsive to good care, however, that no true lover of fruit will profane it with neglect, but will seek, rather, to give it a favorable situation, its choice of soils and such generous care as will insure strong, vigorous, productive vineyards of choicely good fruit.
Grape-growing is a specialists' business, for the culture of the grape is unlike that of any other fruit. The essentials of vineyard management, however, are easily learned. Indeed, care of the vine comes almost instinctively; for the grape has been cultivated since prehistoric times and the races of the world are so familiar with it through sacred literatures, myths, fables, stories and poetry, that its care is prompted by natural impulse. The grape has followed civilized man so closely from place to place through the temperate climates of the world, that rules and methods of culture have been developed for almost every condition under which it will grow, so that every grape-grower may profit by the successes and failures of the generations that preceded him. Grape-growing is not, however, an art wholly governed by rules of the past to be carried on by common laborers who use hands only, but is one in which its followers may make use of science and may put thought, skill and taste into their work.
LAYING OUT THE VINEYARD
Vineyards are laid out for the most part after accepted patterns for each of the great grape regions of America. The vines are always planted in rectangles, usually at a less distance apart in the rows than the rows are from each other, but sometimes in squares. Pride in appearance and convenience in vineyard operations make perfect alignment imperative. Many varieties of grapes, especially of American species, are partially self-sterile, so that some varieties must have others interplanted with them for cross-pollination. This is usually done by setting alternate rows of the variety to be pollinated and the cross-pollinator. All self-fertile varieties are set in solid blocks because of convenience in harvesting.
Direction of rows.
Some grape-growers attach considerable importance to the direction in which rows run, holding either that the full blaze of the sun at mid-day is desirable for vine, soil and fruit, or that it is detrimental. Those who desire to provide fullest exposure to the sun plant rows east and west when the distance between vines is less than the distance between rows; north and south when vines are farther apart in the row than the rows are from each other. When shade seems more desirable, these directions are reversed. Most often, however, the rows are laid out in accordance with the shape of the vineyard; or, if the land is hilly, the rows follow the contour of the declivities to prevent soil erosion by heavy rains.
For convenience in vineyard operations, especially spraying and harvesting, there should always be alleys through a vineyard. On hilly lands, the alleys are located to secure ease in hauling; on level lands they are usually arranged to cut the vineyards into blocks twice as long as wide. An alley is usually made by leaving out a row of vines. Many vineyards are laid out with rows far enough apart so that alleys are not needed.
Distances between rows and plants.
There are great variations in the distances between rows and plants in different regions, and distances vary somewhat in any one region. Distances are influenced by the following considerations: Rich soils and large vigorous varieties require greater distances than poor soils and less vigorous varieties; sometimes, however, it is necessary to crowd a variety in the vineyard so that by reducing its vigor fruitfulness may be promoted. Usually the warmer the climate, or the exposure, the greater should be the distance between vines. Very often the topography of the land dictates planting distances. But while taking in account the preceding considerations, which rightly suggest the distances between plants in the row, convenience in vineyard operations is the factor that most often fixes the distance between rows. The rows must be far enough apart in commercial vineyards to permit the use of two horses in plowing, spraying and harvesting.
Planted in squares, the distance varies from seven feet in garden culture to nine feet in commercial vineyards for eastern America. More often, however, the rows are eight or nine feet apart, with the vines six, seven or eight and in the South ten or twelve feet apart in the rows. Planting distances are less, as a rule, on the Pacific slope than in eastern regions; that is, the distances between the rows are the same, to permit work with teams, but the distance between plants in the rows is less, sometimes being no greater than three and a half or four feet. The rank-growing Rotundifolias of the southern states need much room, nine by sixteen feet being none too much. Sunshine must govern the distance apart somewhat. Grapes picked in the pleached alleys of closely set vineyards of the North and East are few, small and poor; farther south, shade from the vines may be a requisite for a good crop.
The number of vines to the acre must be determined before growing or buying plants. This is done by multiplying the distance in feet between the rows by the distance the plants are apart in the row, and dividing 43,560, the number of square feet in an acre, by the product.
PREPARATION FOR PLANTING
It is impossible to put too much emphasis on the necessity of thorough preparation of the land before planting the grape. Extra expenditure to secure good tilth is amply repaid by increased growth in the grape, and all subsequent care may fail to start the vines in vigorous growth if the land is not in good tilth preparatory to planting. The vineyard is to stand a generation or more, and its soil is virtually immortal, two facts to suggest perfect preparation. The land should be thoroughly well plowed, harrowed, mixed and smoothed. The better this work is done, the greater the potentialities of the vineyard. Here, indeed, is a time to be mindful of the adage which comes from Cato, a sturdy old Roman grape-grower of 2000 years ago: "The face of the master is good for the land."
Preparation is a series of operations in which it is wise to take advantage of time and begin a year before the vines are to be set. The land must be put in training to fit it for the long service it is to render. The two great essentials of preparation are provision for drainage and thorough cultivation. Both, to be performed as the well-being of the grape require, take time, and a year is none too short a period in which to do the work. Moreover, newly drained and deeply plowed land requires time for frost, air, sunshine and rain to sweeten and enliven the soil after the mixture by these operations of live topsoil with inert subsoil.
The ideal soil, as we are often told, resembles a sponge, and is capable of retaining the greatest possible amount of plant-food dissolved in water, and at the same time is permeable for air. This ideal, sponge-like condition is particularly desirable for the grape, especially native species, because the vines of all are exceedingly deep-rooted. Moreover, grapes thrive best in a warm soil. While, therefore, the roots may make good use of nutritious solutions, if not too diluted, in an undrained soil, they suffocate and do not receive sufficient bottom heat. It must be made emphatic that the grape will not thrive in water-logged land.
Unless the land is naturally well drained, under-drainage must be provided as the first step in the preparation of land for the vineyard. Tile-draining is usually best done by those who make land-draining their business, but information as to every requirement of land and detail of work may be secured from many texts, so that grape-growers may perform the work for themselves. In concluding the topic, the reader must be reminded that high and hill lands are not necessarily well drained, and low lands are not necessarily wet even if the surface is level. Often hilltops and hillsides need artificial draining; much less often valley lands and level lands may not need it. To assume, too, that gravelly and shaley soils are always well drained often leads directly contrary to the truth. Sandy and gravelly soils need drainage nearly as often as loamy and clayey ones.
Following tiling, if the land has had to be under-drained, the vineyard should be graded to fill depressions and to make the surface uniform. Usually this can be done with cutaway, tooth or some other harrow, but sometimes the grader or road-scraper must be put in use.
Fitting the land.
Preparatory cultivation should begin the spring preceding planting by deep plowing. If the land has been used long for general farming so that a hard plow-sole has been formed by years of shallow plowing, a subsoil-plow should follow in the furrow of the surface plow, although it is seldom advisable to go deeply into the true hardpan. Fitting the land must not stop here but should continue through the summer with harrow and cultivator to pulverize the soil almost to its ultimate particles. Such cultivation can be sufficiently thorough, and be made at the same time profitable, by growing some hoed crop which requires intensive culture. If the soil lacks humus, a cover-crop of clover or other legume might well be sown in early summer to be plowed under in late fall. Or, if stable manure is available, this generally should be applied the fall before planting. Stable manure applied at this time to a soil inclined to be niggardly puts an atmosphere in the forthcoming vineyard wholly denied the grower who must rely on commercial fertilizers.
The land should be plowed again, deeply and as early in the fall as possible, harrowed thoroughly, or possibly cross-plowed and then harrowed. The land must go into the winter ready for early spring planting and the fall work must be done promptly and with a sturdy team and sharp, bright tools. The grower must keep in mind that no opportunity will offer during the life of the vineyard to even up for slackness in the start and that a vineyard of dingy, unhappy vines may be the result of neglect at this critical time. Good tilth should proceed until the earth is fairly animated with growth when the vines are planted. Plate II shows a piece of land well fitted for planting.
Marking for planting.
Given level land, a well-made marker, a gentle team and a careful driver with a surveyor's eye, and a vineyard may be marked for planting with a sled-marker, a modified corn-marker or even a plow. Some such marker method is commonest in use in laying out vineyard rows, but it is patent to the eye of every passer-by in grape regions that the commonest method is not the best to secure perfect alignment of row and vine. The combination named for good work with any of the marker methods is found too seldom. If the marker method is used, it is put in practice as follows: The rows being marked at the distance decided on, a deep furrow is plowed along the row by going both ways with the plow; this done, small stakes are set in the furrow at the proper distances for the vines, taking care to line them both ways. Planting holes are thus dug in the furrow with the stakes as a center.
Marking by means of a measuring wire or chain is the best method of locating vines accurately in a vineyard. The measuring wire varies according to the wishes of the user from two to three hundred feet or may be even longer. The best wires are made of annealed steel wire about an eighth of an inch in diameter. At each end of the wire is a strong iron ring to be slipped over stakes. The wire is marked throughout its length by patches of solder at the distances desired between rows of vines; to make these places more easily seen, pieces of red cloth are fastened to them. Sometimes this measuring wire is made of several strands of small wire, giving more flexibility and making marking easier, since by separating the strands at the desired points, pieces of cloth may be tied to mark distances.
In using the wire, the side of the vineyard which is to serve as the base of the square is selected and the wire is stretched, leaving at least one rod from road or fence for a headland. With the wire thus stretched, a stake is placed at each of the distance tags to represent the first row of vines. Beginning at the starting point, sixty feet are measured off in the base line and a temporary stake is set; eighty feet at a right angle with the first line are then measured off at the corner stake, judging the angle with the eye; then run diagonally from the eighty-foot stake to the sixty-foot stake. If the distance between the two stakes is one hundred feet, the corner is a right angle. With the base lines thus started at right angles to each other, one can measure off with the measuring wire as large an area as he desires by taking care to have the line each time drawn parallel with the last, and the stakes accurately placed at the marking points on the wire.
Still another method which may be put to good use in laying out a vineyard, especially if the vineyard is small, is to combine measure and sight. The distances about the vineyard are measured and stakes set to mark the ends of the rows around the area. Good stakes can be made from laths pointed at one end and whitewashed at the other. A line of stakes is then set across the field each way through the center, in places, of course, which the two central rows of vines will fill. When these are in place, if the area is not too large or too hilly, all measurements can be dispensed with and the vines can be set by sighting. A man at the end of the row has three laths to sight by in each row and a second man should drive stakes as directed by the sighter. Accurate work can be done by this method, but it requires time, a good eye and much patience in the man who is sighting.
SELECTING AND PREPARING THE VINES
Young grape vines covet life, for they are usually vigorous and not easily injured. Hence, the plants may be brought from a distance without fear of loss. The local nurseryman is, however, a good adviser as to varieties if he is honest and intelligent, and, other things equal, he should be patronized. But if the grower's needs cannot be met at home, he should not hesitate to seek a nurseryman at a distance. This is more necessary with the grape than other fruits because young grapes are well and cheaply grown in certain localities only. With the grape, as with all fruit plants, it is much better to buy from the grower than from tree peddlers.
Unless the buyer knows what he wants, selecting vines is gambling pure and simple. Fortunately, there are several marks of good vines very helpful to those who know them. One should first make sure that the roots and tops are alive to the remotest parts. The vines should have a good clean, healthy look with trunk diameter large enough to indicate vigorous growth, and an ample spread of roots. Large size is not as desirable as firm, well-matured wood and an abundance of roots. Vines with internodes of medium length for the variety are better than those with great length or very short internodes. Such precautions as are possible should be taken to insure varieties true to name, although here the reputation of the nurseryman must be depended on except for the few varieties which may be known at sight in the nursery.
First-grade one-year-old vines are usually better than two-year-olds. Stunted vines are not worth planting and two-year-old vines are often stunted one-year-olds. A few weak-growing varieties gain in vigor if allowed to remain in the nursery two years—three years, never.
Handling and preparing the vines.
The better vines are packed, transported and cared for in the field, the quicker will the roots take hold and the vines make the vigorous start on which so much depends. The nurseryman should be requested not to prune much before packing and to pack the vines well for shipping. The vines should be heeled-in as soon as they reach their destination. If the vines are dry on arrival, they should be drenched well before heeling-in. It sometimes happens that the vines are shriveled and shrunken from excessive drying, in which case the plants often may be brought back to plumpness by burying them root and branch in damp earth, to remain a week or possibly two. To heel-in, a trench should be double furrowed in light, moist soil, the vines spread out in the trench two or three deep, and then earth shoveled over the roots and half the tops, sifting it in the roots, after which the soil is firmed. The vines may thus be kept in good condition for several weeks if need arises.
The vines are prepared for planting by cutting away all dead or injured roots and shortening-in the healthy roots. Grape roots can be cut severely if healthy stubs remain, the removal of small roots and fibers doing no harm, since fibers are of value only as indicating that the vine is strong and vigorous. Fresh fibers come quickly from stout, healthy roots. Most of the fibers of a transplanted vine die, and laying them out in the hole to preserve them, as is so often recommended, is but a useless burial rite. On good healthy vines, the stubs of the roots, when cut back, will be four to eight inches in length. The root system having been considerably pruned, the reciprocity between roots and tops must be taken into account and the top pruned accordingly. To reduce the work of the leaves to harmonize with the activities of the roots, the top should be pruned to a single cane and two, never more than three, buds. The vine is now ready for planting and, the soil being in readiness, planting should proceed apace.
The dangers and difficulties of planting hardwooded plants are greatly exaggerated. The tyro, in particular, is impressed with his responsibilities at this time, and often sends a hurry-up call to experiment station or nurseryman to "send him a man to plant." If the land is properly prepared and the plants in good condition, the operation of planting is easily, quickly and safely accomplished. There is no need, in planting the vine, of such puttering overniceties as laying out the roots to preserve the fibers, watering each vine as it is set, inserting the vine in a gingerly fashion to make sure that it stands in its new abode as it stood in the old, or puddling the roots in pail or tub of water. On the other hand, the slap-dash method of a Stringfellow who cuts off all small roots and uses a crowbar in place of a spade is not doing duty by the plant, and burying the roots deep in the earth or covering them close to the surface is courting failure.
Digging the holes.
This is a simple task in land in good tilth. The holes need only be large and deep enough to hold the roots without undue cramping. Herein is again manifested the wisdom of thoroughly preparing the land; for, in well-prepared land, the hole is really as large as the vineyard. Even in the condition of poor tilth, deep holes are often a menace to the life of the plant, especially if drainage is not provided, for the deep hole becomes a tub into which water pours and stands to soak the roots of dying vines. An extra spurt in digging holes cannot take the place of perfect fitting of the land.
There is nothing to commend the practice of digging holes in a leisure time that all may be ready when the time to plant arrives. The vines will strike root best in the freshly turned, moist soil of newly dug earth, which can be firmly set about the roots when the vine is planted. Neither is time saved in digging beforehand, for the sun-baked and rain-washed sides of holes long dug would surely have to be pared afresh. It is, however, quite worth while to throw the surface soil to one side and that lower to the other, that a spadeful of moist, virile, surface soil may be put next to the roots.
There are, no doubt, some soils in which the holes might be blasted out with dynamite, as, for instance, in a shallow soil with the hardpan near the surface and good subsoil beneath. It is very questionable, however, whether these defective soils should be used for commercial plantings as long as there still remain unplanted many acres in all grape regions of good deep land for the grape. To such as are attracted by "dynamite farming," minute descriptions of methods of use of dynamite and even demonstrations may be secured from manufacturers of the explosive.
Time to plant.
The best time to plant the vine in cold climates is early spring, when sun and showers arouse the spirit of growth in plants, and nutritive solutions proceed quickly and unerringly to their preappointed places. At this time, the much mutilated vine can undertake best the double task of making fresh roots and opening the dormant leaves. Fall planting puts forward the work, thus diminishing the rush of early spring when vineyard operations crowd, and, no doubt, when all is favorable, enables the vines to start a little more quickly. However, there are frequently serious losses from planting in the fall. In cold winters the grip of frost is sufficient to wrench the young vine from its place and sometimes all but heaves it out of the soil. There is, also, great liability of winter-killing in vines transplanted in the autumn, not because of greater tenderness of the plant, but because of greater porosity of the loosened soil which enables the cold to strike to a greater depth. These two objections to fall planting can be overcome largely by mounding up the earth so as practically to cover the vines, leveling the mound in early spring; but this extra work more than offsets the labor saving in fall planting.
In climates in which the soil does not freeze in the winter, the vines may be set in the autumn if all is favorable. Often, however, conditions are not favorable to fall planting in warm climates, since autumn rains frequently soak the soil so that it cannot be placed properly about the roots; and, moreover, in a cold, water-logged soil the inactive roots begin to decay; or the soil may be too dry for fall planting. Under such conditions, it is often better to delay planting in warm climates until spring when better soil conditions can be secured. Fall or spring, the soil should be reasonably dry, warm and mellow when the work is done. The best time to plant must necessarily vary from year to year, and the vineyardist must decide exactly when to undertake planting in accordance with the conditions of soil and weather, mindful that the Psalmist's injunction that there is "a time to plant, and a time to pluck up that which is planted" is subject to several conditions requiring judgment. The grape puts out its leaves late in the spring, making the temptation great to delay planting; late-set plants, however, need special care lest they suffer from the summer droughts which annually parch the lands of this continent.
The operation of planting.
All being in readiness, planting proceeds rapidly. A gang of four men work to advantage. Two dig holes, a third holds the vines and tramps the earth as the remaining man shovels in earth. Except in large vineyards, four men are seldom available, and gangs of two or three must divide the work among its members as best suits conditions. A tree-setting board is not needed in planting grapes, although some growers use it. The man who holds the vines in the hole and tramps as the shoveler fills, must align the plant after the stake is removed and see that it stands perpendicularly in the hole. The stake, a lath, is set in its old place in the hole to serve as a support for the growing vine and to mark it so that the cultivator does not pull up the young plant. The soil must be set firm about the roots of the plant, but zeal in tramping should diminish as the hole is filled, leaving the topsoil untramped, smooth, loose and pulverized, a dust mulch—the best of all mulches—to prevent evaporation.
The depth to which vines should be set is a matter of controversy. This should be governed by the soil more than by any other factor, although some varieties need a deeper root-run than others. The rule to plant to the depth the vine stood in the nursery row is safe under most conditions, although in light, hungry or thirsty soils the roots should go deeper; and, on the other hand, in heavy soils, not so deep. Deep planting is a more common mistake than shallow planting, for roots under most conditions stand exposure better than internment, going down being more natural than coming up for a root seeking a place to its liking.
Watering at planting is necessary only when the land is parched with drought or in regions in which irrigation is practiced. When necessary, water should be used liberally, at least a gallon or two to a vine. After the earth has been firmed about the roots and the hole is nearly filled, the water should be poured in and the hole filled without more firming. Under dry weather conditions, some prefer to puddle the roots; that is, to dip them in thin mud and plant with the mud adhering. In making the puddle, loose loam and not sticky clay is used, as clay may bake so hard as to injure the roots. With puddling, as with watering, the surface soil should be left loose and soft without traces of the puddling below.
Manure or fertilizer about the roots or even in the hole are not necessary or even desirable. If the soil is to be enriched at all at planting time, the fertilizer should be spread on the surface to be cultivated in or to have its food elements leak down as rains fall. In land in which the providential design for grapes is plainly manifested, the vine at no time responds heartily to fertilizers, the good of stable manure probably coming for the most part from its effects on the texture and water-holding capacity of the soil. The newly set plant is not in need of outside nourishment; to put rank manure or strong commercial fertilizers about the roots of a young newly set vine is plant infanticide.
CARE OF YOUNG VINES
Virgil calls the period in the life of the vine between the setting and the first vintage, the "tender nonage," and tells us that at this time the vines need careful rearing; so they do, now as then, American grapes as well as the grapes of ancient Rome. Fortunately, any departure from normal well-being is easily told in the grape, for the color of the leaf is as accurate an index to the health and vigor of the vine as the color of the tongue or the beat of the pulse in man. A change of color from the luxuriant green of thrifty grape foliage, especially the yellow hue indicating that the leaf-green is not functioning properly, suggests that the vines are sick or need nursing in some detail of care. When all goes well, however, the amazing energy of Nature is nowhere better seen among plants than in the growth of the grape, so that much of the care is in the use of the knife; in fact, as we shall see, the grape almost lives by the knife the first two years out.
The first year.
The vines having been pruned and staked at planting, these operations need no attention in the first summer. Many varieties send up several shoots as growth starts, and, except in the case of grafted plants and in the event of the suckers coming from the stock, these should be left to feed the vine and help to establish a good root system. Vines making a strong growth should be tied to the stake, at least the strongest shoot, to keep the wind from whipping it about and to keep the plants out of the way of the cultivator. The only knack in tying is to keep the vine on the windward side of the stake, thus saving the breaking of tying material.
The first year's pruning, though severe, is easily done. All but the strongest cane are cut out and this is pruned back to two buds, nearly to the ground, so that the vines are much as when set in the vineyard. This pruning, and that of the next two years, has as the object the establishment of a good root system and the production of a sturdy trunk at the height at which the vine is to be headed. It is important that the cane from which the trunk is to come be healthy and the wood well ripened. Pruning may be done at any time after the leaves fall, though most growers give preference to late winter. In cold climates it is a good practice to plow up to the young vines for winter protection, in which case the pruning should be done before plowing.
Every detail of vineyard management should be performed with care and at the accepted time in this critical first year. Cultivation must be intensive, insects and fungi must be warded off, mechanical injuries avoided, vines that have refused to grow must be marked for discard, and the vineyard be put down to a cover-crop in early August if it was not earlier planted to some hoed catch-crop.
The second year.
Work begins in the spring of the second year with the setting of trellis posts on which one wire is put up. The vine is not yet ready to train but the slender lath of the first season is not sufficient support, and the one wire on the future trellis saves the expense of staking. Tying requires some care and is usually done with string or bast. As the summer proceeds, suckers from the roots are removed and some growers thin the shoots on the young vine; some think it necessary also to top the growth if it becomes too luxuriant and so keep the cane within bounds. Suckers must be cut or broken off at the points where they originate, otherwise several new ones may start from the base of the old. If the vines are topped, it must be kept in mind that summer pruning is weakening, and the tips of shoots should, therefore, be taken when small, the object being to direct the growth into those parts of the vine which are to become permanent.
Pruning, the second winter the vine is out, depends on the vigor of the plant. If a strong, healthy, well-matured cane over-tops the lower wire of the trellis, it should be cut back so that the cane may be tied to the wire; otherwise the vine should again be cut almost to the ground, leaving but three or four buds. If the cane be left, in addition to sturdiness and maturity, it should be straight, for it is to become the trunk of the mature vine. The training of the young vine is now at an end, for the next season the vine must be started toward its permanent form, instructions for which are given in the chapter on pruning.
The summer care of the vineyard does not differ materially in the second year from that of the first. Intensive cultivation continues, the vines are treated for pests and the annual cover-crop follows cultivation. Many varieties, if vigorous, will set some fruit in this second summer, but the crop should not be allowed to mature, the sooner removed the better, as fruiting at this stage of growth seriously weakens the young vines.
CATCH-CROPS AND COVER-CROPS
A catch-crop is one grown between the rows of another crop for profit from the produce. A cover-crop is a temporary crop grown, as the term was first used, to protect the soil, but the word is now used to include green-manuring crops as well. Catch-crops seldom have a place in most vineyards, but cover-crops are often grown.
Catch-crops are not, as a rule, profitable in commercial vineyards; they may bring temporary profit but in the long run they are usually detrimental to the vines. It may pay and the grape may not be injured in some localities, if such truck crops as potatoes, beans, tomatoes and cabbage are grown between the rows or even in the rows for the first year and possibly the second. Land, to do duty by the two crops, however, must be excellent and the care of both crops must be of the best. Growing gooseberries, currants, any of the brambles, or even strawberries, is a poor procedure unless the vineyard is small, the land very valuable or other conditions prevail which make intensive culture possible or necessary. The objections to catch-crops in the vineyard are two: they rob the vines of food and moisture and endanger them to injury from tools in caring for the catch-crop.
Sometimes the grape itself is planted as a catch-crop in the vineyard. That is, twice the number of vines required in a row for the permanent vineyard are set with the expectation of cutting out alternate vines when two or three crops have been harvested and the vines begin to crowd. This practice is preferable to inter-planting with bush-fruits, yet there is not much to commend it if the experience of those who have tried it is taken as a guide. Too often the filler vines are left a year too long with the result that the permanent vines are checked in growth for several years following. The profits from the fillers are never large, scarcely pay for the extra work, and if the permanent vines are stunted, the filler must be put down as a liability rather than as an asset.
In an experiment being conducted by the New York Agricultural Experiment Station, grapes do not give a very appreciable response to cover-crops in yield of fruit or growth of vine. There seem to be no other experiments to confirm the results at the New York Station, and grape-growers nowhere have used cover-crops very generally for the betterment of their vineyards. There is doubt, therefore, as to whether grapes will respond profitably to the annual use of cover-crops in yield of fruit, which, of course, is the ultimate test of the value of cover-crops, but a test hard to apply unless the experiment runs a great number of years.
Leaving out the doubtful value of cover-crops in increasing the supply of plant-food and thereby producing an increase in yield, there are at least three ways in which cover-crops are valuable in the vineyard. Thus, it is patent to all who have tried cover-crops in the vineyard that the land is in much better tilth and more easily worked when some green crop is turned under in fall or spring; it is not unreasonable to assume, though it is impossible to secure reliable experimental data to confirm the belief, that cover-crops protect the roots of grapes from winter-killing; certainly it may be expected that a cover-crop sowed in midsummer will cause grapes to mature their wood earlier and more thoroughly so that the vines go into the winter in better condition. The only objection to be raised against cover-crops in the vineyard is that pickers, mostly women, object to the cover-crop when wet with rain or dew and usually choose to pick in vineyards having no such crop. This seemingly insignificant factor often gives the grape-grower who sows cover-crops much trouble in harvest time.
Several cover-crops may be planted in vineyards as clover, vetch, oats, barley, cow-horn turnip, rape, rye and buckwheat. Combinations of these usually make the seed too costly or the trouble of sowing too great. Yet some combinations of a leguminous and non-leguminous crop would seem to make the best green crop for the grape. Thus, a bushel of oats or barley plus ten pounds of clover or twenty pounds of winter vetch, a combination often used in orchards, should prove satisfactory in the vineyard. Or, doubling the amount of seed for each, these crops could be alternated, with a change in the rotation every four or six years, with cow-horn turnip or rape. Turnip and rape require at least three pounds of seed to the acre.
The cover-crop is sown in midsummer, about the first of August in northern latitudes, and should be plowed under in the fall or early spring. Under no circumstances should the green crop be permitted to stand in the vineyard late in the spring to rob the vines of food and moisture. The weather map must be watched at sowing time to make sure of a moist seed-bed. Plate III illustrates two vineyards with well-grown cover-crops.
Grape-growers are not in the fog that befuddles growers of tree-fruits in regard to tillage. He is a sloven, indeed, who permits his vines to stand a season in unbroken ground, and there are no growers who recommend sod or any of the modified sod-mulches for the grape. Tillage is difficult in hilly regions and the operation is often neglected in hillside vineyards, as in the Central Lakes region of New York, but even here some sort of tillage is universal. The skip of a single season in tilling stunts the vines, and two or three skips in successive seasons ruin a vineyard. No one complains that grapes suffer from over-tilling as one frequently hears of tree-fruits. There is no tonic for the grape that compares with cultivation when the leaves lack color and hang limp and the vine has an indefinable air of depression; and there is nothing better than cultivation to rouse latent vigor in a scorching summer, or when drought lays heavy on the land.
The tools to be used in tilling grapes vary with the topography of the vineyard, the kind of soil and the preferences of the vineyardist. The best tool is the one with which the ground can be well fitted at least expense. Good work in the vineyard requires at least two plows, a single-horse and a two-horse plow. The latter, except on very hilly land, should be a gang-plow. For commercial vineyards of any considerable size, several cultivators are necessary for different seasons and conditions of the soil. Thus, every vineyard should have a spring-tooth and a disc harrow, one of the several types of weeders, a one-horse and a sulky cultivator. If weeds abound, it is necessary to have some cutting tool, or an attachment to one of the cultivators, to slide over the ground and cut off large weeds. Another indispensable tool in a large vineyard is a one-horse grape-hoe, to supplement the work of which there must be heavy hand-hoes. Very often the surface soil must be pulverized, and a clod-crusher, roller or a float becomes a necessity. A full complement of bright, sharp tools at the command of the grape-grower goes far toward success in his business.
There are several reliable guides indicating when the vineyard needs to be tilled. The vineyardist who is but a casual observer of the relation of vineyard operations to the life events and the welfare of his vines will take the crop of weeds as his guide. It is, of course, necessary to keep down the weeds, but the man who waits until weeds force him to till will make a poor showing in his vineyard. The amount of moisture in the soil is a better guide. The chief function of tillage is to save moisture by checking evaporation and to put the soil in such condition that its water-holding capacity is increased. The physical condition of the land is another guide. Tilling when the soil needs pulverizing furnishes a greater feeding surface for the roots.
Tillage begins with plowing in early spring. Whether provided with a cover-crop to be turned under or hard and bare, the land must be broken each spring with the plow. Plowing is best done by running a single furrow with a one-horse plow up to or away from the vines as occasion calls and then following with a two-horse or a gang-plow. Some growers use a disc harrow instead of the plow to break the land in the spring, but this is a doubtful procedure in most vineyards and is impossible when a heavy green-crop covers the land. Tillage with harrow, cultivator, weeder or roller then proceeds at such intervals as conditions demand, seldom less than once a fortnight, until time to sow the cover-crop in midsummer. About the time grapes blossom, the grape-hoe should be used to level down the furrow turned up to the vines in the spring plowing. Tillage should always follow a heavy rain to prevent the formation of a soil crust, this being a time when he who tills quickly tills twice. The number of times a vineyard should be tilled depends on the soil and the season. Ten times over with the cultivator in one vineyard or season may not be as effective as five times in another vineyard or another season. In some regions, as in New York, the grower is so often at the mercy of wet weather in early spring that the plowing is best done in the fall, and spring operations must then open with harrowing with some tool that will break the land thoroughly.
The depth to till is governed by the nature of the soil and the season. Heavy soils need deep tilling; light soils, shallow tilling; in wet weather, till deeply; in dry weather, lightly. Grape roots are well down in the soil and there is little danger of injuring them in deep tillage. The depth of plowing and cultivating should be varied somewhat from season to season to avoid the formation of a plow-sole. In some regions plowing and cultivating may be made a means of combating insects and fungi, and this regulates the depth of tillage. Thus, in the Chautauqua grape-belt of western New York, the pupa of the root-worm, a scourge of the grape in this region, is thrown out and destroyed by the grape-hoe just as it is about ready to emerge as an adult to lay its eggs on the vines. In all regions, leaves and mummied grapes bearing countless myriads of spores of the mildews, black-rot and other fungi are interned by the plow and cannot scatter disease.
The time in the season to stop tillage depends on the locality, the season and the variety. It is a good rule to cease cultivation a few weeks before the grapes attain full size and begin to color, for by this time they will have weighted down the vines so that fruit and foliage will be in the way of the cultivator. In the North, cultivation ceases in the ordinary season about the first of August, earlier the farther south. Rank-growing sorts, as Concord or Clinton, do not need to be cultivated as late as those of smaller growth and scantier foliage, as Delaware or Diamond. The cover-crop seed is covered the last time over with the cultivator. Plate IV shows a well-tilled vineyard of Concords.
The grape, as a rule, withstands drought very well, several species growing wild on the desert's edge. Even in the semi-arid regions of the far West, where other fruits must always be irrigated, the grape often grows well without artificial watering. Irrigation is practiced in vineyards in the United States only on the Pacific slope and here the practice is not as general as with other fruit crops. Whether the grape shall be grown under irrigation or not is a local and often an individual question answered with regard to several conditions; as the local rainfall, the depth and character of the soil, the cost of water and ease of irrigation. These conditions are all correlated and make about the most complex and difficult problem the growers of grapes in semi-arid regions have to solve. As long, however, as the grape-grower can grow fairly vigorous vines and harvest a fairly bountiful crop by natural rainfall, he should not irrigate; for, even though the crop offsets the cost, there are several objections to growing grapes under irrigation. The vines are subject to more diseases and physiological troubles; the fruit is said to lack aroma and flavor; grapes grown on irrigated land do not stand shipment well, the unduly inflated grapes often bursting; wine-makers do not like irrigated grapes as well as those from non-irrigated lands; and watery grapes from irrigated lands make inferior raisins. It is maintained, however, with a show of reason, that grapes suffer in irrigated vineyards in the ways set forth only when the vines are over-or improperly irrigated.
FERTILIZERS FOR GRAPES
As regards fertilizers, the grape-grower has much to learn and in learning he must approach the problem with humility of mind. For in his experimenting, which is the best way to learn, he will no sooner arrive at what seems to be a certain conclusion, than another season's results or the yields in an adjoining vineyard will upset the findings of past seasons and those obtained in other places. Unfortunately, there is little real knowledge to be obtained on the subject, for grape-growers have not yet broken away from time-worn dictums in regard to fertilizers and still follow recommendations drawn from work with truck and field crops. This is excused by the fact that there have been almost no comprehensive experiments in the country with fertilizers for grapes.
No fallacies die harder than the pronouncements of chemists a generation ago that fertilizing consists in putting in the soil approximately that which the plants take out; and that the chemical composition of the crop affords the necessary guide to fertilizing. These two theories are the basis of nearly every recommendation that can be found for the use of fertilizers in growing crops. The facts applied to the grape, however, are that the average tillable soil contains a hundred or a thousand times more of the chemical constituents of plants than the grape can possibly take from the soil; and many experiments in supplying food to plants show that the chemical composition of the plant is not a safe guide to their fertilizer requirements. Later teachings in regard to the use of fertilizers are: That the quantity of mineral food in a soil may be of far less importance than the quantity of water, and that the cultivator should make certain that there is sufficient moisture in his land so that the mineral salts may be readily dissolved and so become available as plant-food; that far too much importance has been attached to putting chemicals in the soil and too little to the physical condition of the soil, whereby the work of bacteria and the solvent action of organic acids may make available plant-food that without these agencies is unavailable.
These brief and simple statements introduce to grape-growers some of the problems with which they must deal in fertilizing grapes, and show what a complex problem of chemistry, physics and biology fertilizing the soil is; how difficult experimental work in this field is; and how cautious workers must be in interpreting results of either experiment or experience. An account of an experiment in fertilizing a vineyard may make even more plain the difficulties in carrying on experiments in fertilizing fruits and the caution that must be observed in drawing conclusions.
AN EXPERIMENT IN FERTILIZING GRAPES
The New York Agricultural Experiment Station is experimenting with fertilizers for grapes at Fredonia, Chautauqua County, the chief grape region in eastern America. The experiment should be of interest to every grape-grower from several points of view. It not only shows that there are many and difficult problems in fertilizing grapes, but also the results of the use of manure, commercial fertilizers and cover-crops in a particular vineyard; it suggests the fertilizers to be used and the methods of use; and it furnishes a plan for an experiment by grape-growers who want to try such an experiment and draw their own conclusions. An account of the experiment and the results for the first five years follows:
Tests at Fredonia.
"In the vineyard at Fredonia eleven plats were laid out in a section of the vineyard where inequalities of soil and other conditions were slight or were neutralized. Each plat included three rows (about one-sixth of an acre) and was separated from the adjoining plats by a 'buffer' row not under test. One plat in the center of the section served as a check, and five different fertilizer combinations were used on duplicate plats at either side of the check. Plats 1 and 7 received lime and a complete fertilizer with quick-acting and slow-acting nitrogen; Plats 2 and 8 received the complete fertilizer but no lime; on Plats 3 and 9 potash was omitted from the complete fertilizer combination; Plats 4 and 10 received no phosphorus; Plats 5 and 11, no nitrogen; and Plat 6 was the check. The materials were applied at such rates that they provided for the first year 72 pounds of nitrogen per acre, 25 pounds of phosphorus and 59 pounds of potassium; and for each of the last four years two-thirds as much nitrogen and phosphorus and eight-ninths as much potassium. The lime was applied the first and fourth years in quantity to make a ton to the acre annually. Cover-crops were sown on all plats alike and were plowed under in late April or early May of each year. These differed in successive years, but included no legumes. The crops used were rye, wheat, barley and cow-horn turnips separately and the last two in combination.
"The cultivation differed only in thoroughness from that generally used in the Belt, the aim being to maintain a good dust mulch during the whole growing season. Pruning by the Chautauqua System was done throughout by one man, who pruned solely according to the vigor of the individual vines and left four, two or three, or no fruiting canes as appeared best. The vineyard was thoroughly sprayed, all plats alike.
"Low winter temperatures, affecting immature wood and buds caused by unfavorable weather of the previous season, reduced yields materially during two of the five years, and practically neutralized any anticipated benefit from fertilizers. Following the first of these low-crop years, came a season, 1911, in which favorable conditions, acting upon vines left undiminished in vigor by the light crop of the previous year resulted in heavy and quite uniform yields on all the plats.
"The yields for the five years are shown in Table I; and a summary showing the average gains from each treatment is given in Table II, with the average financial balance after deducting the cost of fertilizer application from the increased returns from the plats receiving them.
TABLE I.—YIELD OF GRAPES (TONS PER ACRE) IN FERTILIZER EXPERIMENTS
========================================================================= Plat. 5-year No. 1909 1910 1911 1912 1913 avg. -+ -+ + + + + + Tons Tons Tons Tons Tons Tons 1 Complete fertilizer; lime 4.48 2.10 5.37 3.46 2.14 3.51 2 Complete fertilizer 4.76 2.21 5.71 4.30 2.83 3.96 3 Nitrogen and phosphorus 5.17 2.14 5.61 4.00 2.25 3.83 4 Nitrogen and potash 4.25 2.55 5.64 4.10 2.85 3.87 5 Phosphorus and potash 3.41 2.00 5.44 4.35 1.78 3.39 6 Check 3.38 2.10 5.32 3.60 1.24 3.12 7 Complete fertilizer; lime 4.69 2.38 5.62 4.80 3.04 4.10 8 Complete fertilizer 4.66 2.07 5.71 4.98 2.72 4.02 9 Nitrogen and phosphorus 4.99 2.04 5.35 4.89 2.61 3.97 10 Nitrogen and potash 4.79 2.26 5.91 4.89 3.07 4.18 11 Phosphorus and potash 4.99 1.87 5.03 4.21 1.97 3.61 =========================================================================
TABLE II.—AVERAGE INCREASE IN GRAPE YIELDS AND AVERAGE FINANCIAL GAIN FROM FERTILIZER APPLICATIONS
N = nitrogen, P = phosphorus, K = potassium, Ca = lime. Gains in tons per acre.
======================================================================== N, P, N, P, N, P. N, K. P, K. K, Ca. K. + -+ -+ -+ -+ - Tons Tons Tons Tons Tons First plat of pair 3.51 3.96 3.83 3.87 3.39 Second plat of pair 4.10 4.02 3.97 4.18 3.61 -+ -+ -+ -+ - Average 3.80 3.97 3.90 4.02 3.50 Check plat 3.12 3.12 3.12 3.12 3.12 -+ -+ -+ -+ - Average gain .68 .85 .78 .90 .38 Average financial gain $5.82 $13.84 $14.05 $18.54 $6.99 ========================================================================
From this last table the benefit from nitrogen appears quite evident since every combination in which it appears gives a substantial gain over the one from which it is absent. Phosphorus and potassium without the nitrogen, lead to only a slight increase over the check; and lime appears to be of no benefit. Financially, the complete fertilizer and lime combination, the nitrogen and phosphorus combination and the phosphorus and potassium combination failed to pay their cost in five of the ten comparisons; the complete fertilizer was used at a loss four times out of ten; and the nitrogen and potassium combination three times out of ten. Lime had no appreciable effect on either vines or fruit.
"No effect of the fertilizers on the fruit itself, aside from yield, was shown for the first three years; but in 1912, and even more markedly in 1913, the fruit from the plats on which nitrogen had been used was superior in compactness of cluster, size of cluster and size of berry. In 1912 also, when early ripening was a decided advantage, the fruit on the nitrogen plats matured earlier than that on the check plats. In 1913 the favorable ripening season and the smaller crop tended to equalize the time of ripening on all plats. The grapes on the phosphorus-potassium plats were better in quality than those in the check plats but not as good as those on the plats where nitrogen was used.
"Other indexes also show plainly the benefit from nitrogen in this vineyard; for size and weight of leaf, weight of wood produced and number of fruiting canes left on the vines were all greater where fertilizers, and particularly nitrogen, had been used. The three-year averages (1911-1913) of the measurements for these characteristics are shown in Table III:
TABLE III.—COMPARATIVE PRODUCTION OF LEAVES, WOOD AND FRUITING CANES ON GRAPE VINES DIFFERENTLY FERTILIZED
(Averages for three years.)
======================================================================= FERTILIZER APPLICATION LEAF WOOD FRUITING WEIGHT PRUNED CANES LEFT + + + Grams. Lbs. Complete fertilizer; lime 1,033 1,295 2,468 Complete fertilizer 1,010 1,367 2,609 Nitrogen and phosphorus 1,047 1,272 2,585 Nitrogen and potassium 1,069 1,401 2,646 Phosphorus and potassium 964 1,086 2,326 Check 930 915 2,110 =======================================================================