Part 17

_Points to be Observed in Grafting._--The main object in grafting is to properly join the scions and the stock. The point of junction should be the cambium layer, or what is commonly called the inner bark. If a cutting of a vine is cut off smoothly and placed in the ground, the callus soon begins to form at the lower end. This callus, which is seen to exude from the green layer between the hard wood and the bark, is fed by the sap in the cutting descending through the cambium layer and forming new cells at its free end. If this callus joins a similar callus of the cambium or green layer of the stock, the two calluses unite and form together a new vine, in which the top consists of the new scion and the root of the old vine. The junction of the two is the place where the cambium surface of the scion met the cambium of the stock. In the scions, the cambium lies very close to the exterior layer of the cutting, the bark here being very thin, while in the old stock the cambium is situated many times deeper in, the outer layer or the bark being very thick. It is not necessary that the cambium layers of the two should meet or join all along the cut surface, and a few points of contact and junction is sufficient, although it is better to have as large a junction surface as possible. If the two cambium layers do not meet, the scion will not grow, or, as it is called, take. The scions must be dormant when being grafted, and, if their buds have begun to swell, they will probably not take, or at least success is less certain. In order to keep them dormant they should be cut early in winter, and then be buried in cool and only slightly moist earth, either in a cellar or on the north side of a house, where the sun and heat will not strike them and cause them to start their buds. If the callus should form, or even root, the callus and roots may be cut away without great injury to the cuttings. If the cuttings are dry, they should be soaked for a few hours in tepid water, and afterwards buried in moist sand. This treatment is often useful for imported cuttings which have been injured in transit. They often recover vigor wonderfully fast, and should never be given up for lost as long as there is any green-colored cambium left, in which the sap may again be brought into circulation.

_Various Methods of Grafting._--The general way to graft is to graft on old stocks. Vines of one variety are thus changed into the variety we wish to grow, and from which the scions are taken. The first step is to dig away the soil from the vines down to the first roots, which should be done by a separate gang of men. Next the stocks are sawed off horizontally at the first roots, or say from four to six inches below the surface of the soil. This should also be done by separate hands so as to insure rapidity and skill in the work. Some grafters saw off the stocks somewhat slanting, so as to cause them to shed the sap which always exudes from the stump. Next in order comes the splitting of the wood of the stock and the insertion of the grafts. This requires care and skill, and should not be done by careless hands.

The splitting of the stock is done in several different ways, and to accomplish it we can either use a knife and a wooden mallet or a hand-saw. If the former is used, the knife must be sharp and thick, so as to stand the blows of the mallet. Some growers even use a sharp chisel. If a saw is the tool used,--and I prefer it every time,--the edges of the old wood should afterwards be pared off smoothly with a sharp knife, so as to leave no rough marks of the teeth of the saw. The stock is split straight across, as in the cleft graft, and one scion is then inserted at each end of the cleft on opposite sides of the stock; or the stock is split on one side only, care being taken that the cleft does not extend across the stump, and in this cleft a scion is carefully fitted as before; or a wedge-shaped piece may be sawed out or cut out of the stock, and of the size that can be fitted by a scion. It makes but little difference what method is used, as with ordinary care and skill the scions will take quite readily. Even if they should entirely fail, the same stocks may be grafted over next fall or next year, as they keep their vitality almost unimpaired for years after they are cut. It is only necessary to saw them off until fresh wood is reached.

The next work is to insert the scions. They should never be longer than sufficient to have one eye above the surface of the soil, two or three eyes to the scion being generally enough. The cuttings are first cut in sufficient lengths in the field, or on the spot, and there pared to fit the cleft in the stock. If prepared in the house, they are apt to dry out and become ruined. By keeping them in water they may be kept fresh, but this greatly injures their quality. The best way is to bring the cuttings out to the vineyard wrapped up in wet sacks, and to cut and pare them on the spot where they are to be grafted. With a sharp knife the two opposite sides of the scions are pared off tapering, but not necessarily to a fine point. The scion is then fitted in the cleft, a small wooden wedge being useful for holding the latter open while the scion is fitted. If the stock closes tightly upon the graft, no tying is required, but, if the grip of the stock is not sufficient, tying is needed. Cotton cloth, manilla rope or anything that will hold the two together will answer the purpose. The stocks and scions will both dry slightly, and the tying should therefore be secure and tight.

A piece of bark of the vine is next placed over the cleft, so as to prevent any soil from falling in the cleft, and very careful grafters use a paste made of a mixture of two parts of adobe or clay and one part of cowdung, for covering both the cleft and the sides of the grafts outside of the tying. A stout stake is driven in the ground close to the graft, and the two tied together in order that the graft may not give or be disturbed in the least. The hole is next filled with soil, which should be packed tightly and heaped above the scion, thus forming a small mound above the ground all around the graft. The soil should not be disturbed until the new shoots are well above the ground and have begun to harden their wood, at which time the security of the graft is fully assured. One or more of the grafts may be left growing for the first year, and later on all except one graft are cut off so as to give the vine only one trunk.

In grafting on resistant stocks, the latter generally being smaller then old stocks, a different graft may be used, such as the whip graft. This graft should be above or at least near the top of the ground in order to prevent the scion from taking root, the latter’s roots not being resistant to the phylloxera. Such grafts should be carefully covered with the clay mixture, and soil should be heaped up over their tops. To prevent the scions from drying out, their tops may also be covered with grafting wax.

_Stocks and Their Influence._--The old stock has a decided influence on the scion and the new vine. Which stock is the best on which to graft the Muscat has not yet been determined, but we may presume that any strong and healthy growing variety will answer our purpose. During the first year, and also during the second year, in many instances the new vine assumes a character half way between that of an old-stock variety and that of the variety of the scions. Thus I have seen Muscats grafted on Sultanas and Zinfandels which were almost identical with these varieties. If I had not positively known that they were the tops produced from Muscat scions, I would never have believed them to be anything else than suckers from the old stocks. The leaves, berries and branches of these Muscats were the first year exactly like Sultanas. The berries of those grafted on black grapes were, however, in this instance, not black but white, but I have heard of other instances in which they were partially colored. Some vines, again, showed characteristics of both varieties, the leaves generally being similar to the old stock, while the grapes showed the characteristics of the Muscats. This bastardity, however, wears off in a year or two, and finally the vine assumes the full characteristics of the scion variety. When this takes place it is evident that the sap of the scion or the top of the vine has either changed the root, or through its quantity overpowered the effects of the root-sap.

Muscats grafted on Malagas, Feher Szagos, Sultanas and Zinfandels all do well in time, and in many instances bear even better than Muscats on their own roots. Our experience in grafting the Muscat is, however, limited, and we do not know with any certainty which roots are the most favorable or the most unfavorable on which to graft the Muscat grape. I have seen grafted Muscats on wine stocks which did not do well as regards bearing, while the growth of the vines was rather vigorous. These varieties mentioned above are, however, suitable stocks for Muscat grafts. I learn from Mr. R. C. Kells of Yuba City that the late Dr. S. R. Chandler of the same locality cleared the third year seventy-five dollars per acre from Muscats grafted on Mission vines. This must be considered as very successful, especially as I have heard of other instances where similar grafts did not bear sufficiently the third year to pay for the labor of caring for the vineyard work that year.

VARIOUS SUMMER WORK.

_Sulphuring._--Sulphuring the vines is now considered a most necessary operation, and without doing it well and in time no good crops can be relied upon. It is true that good crops of grapes are sometimes had without sulphuring, but this is only due to chance; the absence of mildew, and immunity from disease of unsulphured vines are rare, even in otherwise most perfectly kept vineyards.

The sulphuring consists in thoroughly dusting the growing vines, leaves, branches, flower buds and berries with powdered sulphur. The first sulphuring must be done when the grapevines leaf out in the spring, and, when the young shoots are about six inches long, it is about time to commence. Many growers sulphur only once, some go over their vines two times, but our most successful growers,--those who get the best and largest fruit crop of grapes and bunches,--sulphur in unfavorable seasons three or four times. The second sulphuring is done just before the blossoms open, and may even, provided the weather remains cool and windy, be done in the open blossoms with great benefit to the setting berries. Miss M. F. Austin of Fresno was the first to successfully sulphur in the open blossom, the result being very large crops. But not all have been as successful as she, and one of our most experienced vineyardists and raisin-growers, T. C. White, prefers to sulphur just before the blossom opens, as, in case of very warm weather when the sulphur is thrown on the blossom, the latter is apt to blast. We are therefore on the safe side if we sulphur just before the buds have opened, and after the grapes have set. But on cold, windy days when one of the cold electric northwest winds are sweeping down the valleys, sulphuring must be done whether the blossom is open or not, as it is just at this time the sulphur is required the most, in order to counteract the formation of the first stage of the powdery mildew. The vapor of the sulphur destroys the germs of the mildew, and thus prevents the latter from causing the grapes to fall off. After the grapes have fully set, no further sulphuring is required except in the case of heavy rains or in continued cloudy weather, when there is always danger that the mildew will reappear. If heavy rains should occur during the summer, a renewed sulphuring is always necessary or at least advisable, but in ordinary seasons no sulphuring is needed after the berries have set well, as the germs of the mildew are then sufficiently injured to not develop later in the season.

Sufficient sulphuring is always noticeable in the vineyard by its smell, and, when this smell is strong and pronounced, no further sulphuring is required. The sulphur is applied to the vines either by the “dredger” (or dust-can) or by a pair of sulphur bellows. The dredger is used when the vines are small, while the bellows are necessary to spread the sulphur evenly when the vines have reached a certain size. Many growers use, during the first sulphuring, small burlap bags filled with sulphur. The meshes of the burlaps are large enough to allow the sulphur to go through. The sulphur should be finely pulverized to be effective, and the sublimated French sulphur is by many considered the best. The cost of sulphuring varies according to the size of the vines, but is generally about three dollars per acre. Young vines under three years of age require little sulphuring, while older vines require a great deal. About ten tons of sulphur will be enough for 160 acres.

_Tying Over._--The tying over of the branches is another vineyard operation much used in the interior raisin districts, generally in the end of June or the middle of July. It consists in so bending and tying the long, straggling branches of the vine that they will shade the grapes hanging in the center. The long branch is bent, not in a direct line towards the center, as it would then expose too many of the lower grape bunches, but in a spiral direction round the vine. If there is any fear that the grapes will be exposed and sunburned, and the vines have not been properly summer pruned, the tying over is the only process by which great loss can be prevented and the grape crop saved. In tying over, no twine is used. The end of the long branch is twisted and fastened to other branches, and, when the grapes are ripe and the picking season comes, a single light pull will suffice to untie all and allow the grapes to be picked. Great care should be used in tying over, lest the lower branches become exposed and sunburned. Careless or inexperienced laborers will often accomplish a great deal of work and a great deal of harm in an incredibly short time. I have seen vineyards where more harm was done by tying over than by the sun and wind combined.

_Covering the Vines._--Instead of tying over, many vineyardists now cover the vines, and place the covers on the open center of the vine, in order that they may protect the grapes from exposure to the sun. This is done in June, several days before the hot spell is expected. The last week in June is the best time almost everywhere in California, as the vines are then open in the center, and any unusually hot weather would easily cause the grapes to sunburn. The process of covering is very simple. With a pair of shears the longest branches are clipped off and immediately placed on the open center. This is generally enough to prevent the exposed grapes in the center of the vine from being scalded. More than half a dozen branches will seldom be required, and at picking time these dry branches must first be thrown off, so as to give the picker access to the grapes. The covering of the vines is a better process than tying over, requiring less work and being more quickly performed. It is especially useful for old vines, as the grapes of young vines are principally exposed from the sides.

_Thinning the Crop._--The proper thinning of the crop should be done by pruning. If the proper amount of wood is left, no thinning out of the grapes is needed. If a few show-grapes or extra large raisins are needed for exhibiting purposes, they can be produced by a judicious cutting of the majority of the grapes from any single bunch. If the free half of the bunch is cut off, the part that is left will produce very large grapes. This operation is, however, never likely to enter as a regular vineyard operation in our vineyards, as with us labor is too scarce. The object of our raisin industry is to produce cheap medium-sized raisins of good quality, to be used by the masses of the people, instead of a smaller quantity of very large grapes, which could only be used by the rich.

_Ringing the Vines._--This consists in removing a part of the bark all around a cane. In France and Greece a special instrument is made to perform this operation quickly and carefully. A ring of bark half an inch wide is all that is required to have the desired effect. The vines are ringed when the grapes are half grown, and only a few canes are ringed on each vine. The effect of ringing is to greatly increase the crop of grapes, also to produce the grapes earlier in the season. So far this process has not been used in California to any extent. In the Grecian Islands, where currants are raised, this ringing has been practiced for years, with more or less beneficial effect. The sap in the cane that is ringed is prevented from again returning to the root, and goes to produce a larger quantity of grapes above the ring. But thereby the cane is seriously injured, and often to such an extent that it must be entirely removed the following season. Care must therefore be taken to leave enough unringed branches to serve as fruit-bearing wood the following year. If done with care and good judgment, the ringing does no great injury to the vine. For a fuller account of the process, see article on Currants.

_The Vineyard Labors of the Year._--The following synopsis of the various labors in a raisin vineyard can only be of interest to the beginner, or to any one who contemplates engaging in the raisin business. The data given are only approximate, as they must differ in different localities, or according to the changing of the seasons:

_December._--After the first frost, or when the vines are dormant, planting new vines and cuttings may begin. Pruning the old wood. Burning the prunings. Manuring the soil.

_January._--Plowing, cultivating and planting.

_February._--Cultivating and plowing.

_March._--Grafting the grapes and finishing plowing.

_April._--Hoeing the vines and cultivating. Sulphuring and suckering.

_May._--Sulphuring and summer pruning.

_June._--Hoeing. Covering or tying over the vines.

_July._--Irrigating where needed. Fixing trays and sweatboxes.

_August._--Distributing trays and sweatboxes in the vineyard. Picking the first crop. Packing should begin as soon as possible.

_September._--Picking, drying, turning the trays, reversing, taking up.

_October._--Picking the last of the second crop. Packing continues.

_November._--Hauling in, stacking and cleaning off trays and sweatboxes. Irrigating and manuring the land. New land should be prepared for planting, which should begin as soon as the first frost has killed the leaves of the vine.

PRUNING.

_Winter Pruning, or Pruning Hard Wood._--The pruning of vines comprises two different processes. The first one has for its object the shaping of the vines, the second one similarly the shortening of the branches properly so as to enable them to bear better fruit. These two points must always be kept in view, much more so of course during the first few years, before the vines have reached their bearing age. But even in after years the pruning must be so conducted, that the shape of the vine is not changed so as to interfere with the work in the field, or with the perfect development of the grapes. As regards the shape of the vine, it has been decided that in our raisin districts the Muscat requires to be pruned low, in order to properly protect the grapes from sun and wind. The head should be as low as possible, or even rest on the ground, and in no instance be more than a few inches above the same. Many of the bunches will then rest on the ground or hang a few inches above it, and experience shows us that such low bunches are the best and those which produce the finest raisins. Tall Muscat vines never produce as sweet and as large bunches or grapes as those headed low, and their grapes are apt to sunburn or be otherwise checked in their growth. During the first year, the young vine should be cut back to a single stem, it being enough to leave two or three eyes above the ground. The second season these canes should all be cut away except three, which are to form the future head of the vine. Each one of these may be cut to two eyes, thus leaving six eyes on the vine. In the majority of vines, the head should by this time have been formed, as the following year will be the first year in which the vines will bear.

When Muscat vines have grown two seasons, they should be pruned for fruit. The third season will always give some fruit, while, in many localities where the vines have been well cared for, the yield may be quite large and pay handsomely. No direction as to pruning, which will apply to every locality or to every vine, is possible. In different localities the climatic and other conditions are so variable that the methods of pruning may be modified. Where the vines grow strong and vigorous more wood should be left. In cool and sheltered places the vines should be given a greater spread to allow more sun and air to enter. In warm localities, with a broiling sun, the principal object in pruning should be to properly shelter the grapes. There is danger, or at least there are great disadvantages in pruning either too long or too short, and in leaving too many or too few spurs. In pruning too long, or leaving too many eyes, the shape of the vine is changed or even seriously injured. In leaving too many spurs, the vines may bear too many and too small grapes. To find the medium between these extremes is always the great object and study to which the grower should devote his attention. In rich and moist soils which produce strong vines, more eyes should be left, and in sandy, poor soil a few eyes may suffice to cause the vine to bear much more that it can properly mature and perfect. The year before the vines bear their first good crop, the spurs left should not exceed three or four, and each spur should not have more than two eyes, including the eye nearest the old wood, which eye is often overlooked and not counted in. The next year a few more spurs may be left, but at no time should each spur be allowed to carry more than two eyes. If more eyes are left, the lower eyes will not develop, and the only thing attained by such pruning is to increase the size of the head, and to place the leaves and the grapes farther away from the center of the vine.