The Two-trunk Kniffin, ill.u.s.trated in Fig. 20, is another modification with the aim of securing greater fruitfulness. This method also provides an equal number of buds on both wires. Two trunks are brought from the root, one to the upper, the other to the lower wire. The fruiting canes are taken off and are disposed of as in the Four-cane Kniffin. The trunks are usually tied together to hold them in place.
This method is in restricted use in the Hudson River Valley where it is known under the name given here and as "Double Kniffin" and "Improved Kniffin." In experiments in training grapes at Fredonia, New York, under the direction of the New York Experiment Station, this method proves to be one of the poorest in growing Concords. The grapes fall short in size of bunch and berry and do not mature as well as under the other drooping methods of training.
[Ill.u.s.tration: FIG. 20. Two-trunk Kniffin training.]
_The Y-trunk Kniffin._
Still another modification of the Kniffin method is one in which a crotch or Y is made in the trunk midway between the ground and the lower wire. The theory on which this method is founded is that sap for the lower canes is better supplied than in a straight or continuous trunk and that the lower canes thus become as productive as those on the upper wire. The theory is probably wrong but is accepted by many notwithstanding. The methods of pruning, renewing fruiting-wood and tying are the same as in the Single-stem Kniffin, except, of course, that each stem supports two canes and two spurs. This method was in somewhat common use some years ago in parts of western New York but is now disappearing.
_The Munson method._
An ingenious modification of the Kniffin principle was devised by Elbert Wakeman, Oyster Bay, Long Island, and afterwards improved and brought into prominence by the late T. V. Munson of Denison, Texas; it is now much used in southern vineyards. The method is described as follows by Munson:[14]
"The posts should be of some durable strong wood, such as Bois d'Arc (Osage), Cedar, heartwood of Catalpa, Black Locust or White Oak. The end posts of every row should be large and strong and be set three and one-half or four feet in the ground and well tamped. The intermediate posts, which may be much lighter than the end posts, should be six and one-half or seven feet long and set two to two and one-half feet in the ground, with twenty-four feet s.p.a.ces between posts, which will take three vines, eight feet apart, or two vines twelve feet apart.
After the posts are set, a three-eighths-inch hole should be bored through each post, four feet from the surface of the ground, in the direction in which the row runs, leaving six inches or more of post above the hole. These holes are for the admittance of the middle, lower wire of the trellis.
"For each end post prepare for cross-arm, a piece of two by four hard pine or oak, two feet long, and at one inch from either end, and one inch from the upper side, bore a three-eighths of an inch bit-hole, or saw into upper side half an inch, which will take less time and do as well, to pa.s.s the lateral wires through, and in the middle of the lower side, saw a notch one-half inch deep. For each intermediate post, prepare a board of similar wood, two feet long, one inch thick by four broad, and likewise bore or notch.
"Through the holes in the posts run a No. 11 galvanized wire, fasten at one end, tighten at the other end by a wire stretcher and fasten.
This will be the middle and lower wire of the trellis, and all that will be needed the first year, when the young vines are trained up a string, tied from the vine (when set) to the wire, and along it. The arms, and the two lateral wires which they bear, need not be put on the trellis until after the vines are pruned and tied the next winter.
To put on the cross-arms, use no bolts or nails, only No. 11 galvanized wire.
"Each end cross-arm is placed inside the post, and against it on top of the wire, already through the posts, notch-side downward, straddling the wire, to keep it from sliding. Then take a piece of same size wire, about seven feet long, pa.s.s one end through the bit-hole or saw-notch, in one end of arm and fasten it by looping and twisting about six inches of the end back upon itself, then while one person holds the cross-arm in place, the operator carries the wire down around the post once near the ground, staples it on each side and brings the other end up to the opposite end of arm, puts it through the bit-hole, or saw-notch, draws it tightly, keeping the arm level, and fastens the end of the wire as was done the other. Wire nippers and pliers will be needed for this work. Then take another piece of wire about two feet long, and put it twice around the cross-arm and the post where they come together, above the middle wire, and firmly tie them together, crossing the wire as it goes around. This will hold the arm in place and not weaken or split the arm as do nails and bolts, and will be longer-lasting, quicker and cheaper, and more elastic, so that when struck by the hames or collar in cultivation, it gives a little, receiving no damage.
"Likewise place the cross-arms on the intermediate posts, leaving the ends of the wire projecting about six inches after fastening, for a purpose soon to be mentioned. Then draw the two lateral wires through the bit-holes in the ends of the arms, or drop into the saw-notches, if such are made, throughout the row, tighten with the wire stretcher and fasten. Then return along each lateral wire, wrapping ends of wire at the ends of the arms very closely and tightly around the through-going lateral wires, as telegraph and telephone wires are wrapped in splicing. This is quickly done with the proper pliers, and prevents the arms from slipping out of proper position. Now the trellis is complete, and will need little or no repairs, and looks very neat, especially if painted.
"Pruning and training on the Munson trellis is very simple and easy with a little instruction for a few minutes with a vine or two pruned for example. The vine the first season is allowed to grow up on to the middle wire by a string around which it is coiled by hand, by going over the vineyard once or twice until the selected shoot of each vine is upon the wire, after which it is allowed to ramble at freedom over the wires. By getting on to the trellis the first year, one strong shoot, and allowing no other to grow, a partial crop can be had the second year, without damage, on all but weak growers, like Delaware, that should not be allowed to bear until the third year. At the first regular pruning (all prunings should be done in November or December, after leaf fall, and never so late as to cause the vines to bleed), the vine should be cut back to two or three buds that have reached the middle wire, if weak growers, if strong, with heavy growth, six or eight buds each, to two arms, one going each way along the lower wire from where the ascending vine first touches the wire. After the vines are thus pruned, the outer end of each arm is firmly tied to the lower wire, along which it is gently coiled. These two ties hold the vine firmly in place. The buds on the arms push and ascend, pa.s.sing over the lateral wires, clinging thereto with their tendrils, and hang over like a beautiful green drapery shading the fruit and body of the vine according to its natural habit.
[Ill.u.s.tration: PLATE XI.--Concord (2/3).]
"On the canopy trellis, all the summer pruning required is, to go through the vineyard at or a few days before blooming time, and with a light sharp butcher knife, clip off the tips of all advanced shoots to be left for bearing, leaving two or three leaves beyond the outer flower cl.u.s.ter. From the shoots near the crotch, selected for bearing arms the next year, pick the flower cl.u.s.ters, and strip off or rub off all shoots and buds that start on trunk of vine below crotch. This latter is very important, as such shoots, if left, eat up the nourishment of the land with no return but added work at pruning time.
"It will be found that the shoots at the ends of the arms usually start first and strongest, and if not clipped back, will not allow the buds back toward the crotch to start well, but if clipped, all other desirable buds then push.
"In about six to ten days after the first clipping, a second one is usually necessary, especially if the weather is moist and warm, and the land rich. The first clipped shoots, as well as those not clipped the first time, will need clipping back this time, the end buds on the first clipped having pushed vigorously.
"At a second year's pruning and others following, the old arms with all the bearing shoots on them are cut off down to the new arms and the new arms cut back to lengths they can fill with fruit and well mature. In this, critical judgment and knowledge of capabilities of different varieties are more required in the pruner than in any other of the training work. Some varieties, such as the Delaware, cannot carry more than three to four arms, two feet long, while Herbemont can more easily carry four arms each eight feet long, hence such as Delaware should be planted eight feet or less apart, while Herbemont and most of the Post-Oak grape hybrids, should be twelve to sixteen feet apart. In other words, each variety should be set that distance apart that it will fill the trellis with fruit from end to end, and mature it well, so as to better economize s.p.a.ce.
"By the third year, the vine should come to full bearing, and be pruned with four bearing arms, two to go each way along the lower wire of trellis, gently coiling around the wire, one arm in one direction, the other in opposite direction, and should be in about equal lengths, so that one firm tie with jute yarn, near the ends, will be all the tying the vines will need--that is, two ties to each vine--the least required by any trellis system, and the pruning is also simplest and the results every way the best.
"Some of the advantages of this trellis are its cheapness, its simplicity, bringing the work up breast-high so that pruning, tying, harvesting, spraying, can be done in an erect position, saving back strain; perfect distribution of light, heat and air to foliage and fruit; shielding from sunscald and birds; giving free ventilation and easy pa.s.sage of wind through the vineyard without blowing down the trellis or tender shoots from the vines, and allowing ready pa.s.sage from row to row, without going around, thus getting larger and better crops at less expense and increasing length of life of vineyard and the pleasure of taking care of it."
This method does not seem to be adapted to the needs of grapes in northern vineyards, and in the South such weak-growing sorts as Delaware do not thrive when so trained. Several "modified Munson methods" are in use in the southern states, but those most commonly employed do not depart greatly from the method here described.
_III. Shoots horizontal_
_Hudson horizontal._
There is now in use but one method of training shoots horizontally. In this method the trellis is made by setting posts eight or ten feet apart and connecting them by two slats, one at the top of the posts, the other about eighteen inches from the ground. Strands of wire are stretched perpendicularly between the slats at ten- or twelve-inch intervals. One cane is trained from a trunk from one to two feet high on the trellis; it rises perpendicularly from the ground and is tied to the top slat. The shoots push out right and left and are tied horizontally to each wire as they reach it. The cane is usually allowed to bear about six shoots on each side. The grapes set at the base of the shoots so that the bunches hang one over the other, making a pretty sight. This method is too expensive for a commercial vineyard but is often used in gardens and for ornamental plantings. Only weak-growing sorts, as Delaware, Iona or Diana are adapted for this method. Delaware does remarkably well under horizontal training. The use of slats and wires in horizontal training are often reversed. The alternative from the method just described is to set posts sixteen or eighteen feet apart upon which are strung two wires as for the ordinary trellis. Perpendicular slats are then fastened to these wires to which the shoots are tied. Two slats, fifteen inches apart, are provided on each side of a fruiting cane, which, with the slat for the support of the cane, give five to a vine. Or the vine may be supported by a stake driven in the ground.
In both of these methods, a shoot must be taken out from the head of the vine each season for the next season's fruiting-wood. This shoot is tied to the central wire or slat and is now allowed to fruit. Thus the vine starts each spring with a single cane. Grapes are grown under these horizontal methods chiefly, if not only, in the Hudson River Valley and even here they are going out of use.
TRAINING ON ARBORS, PERGOLAS AND AS ORNAMENTALS
The grape is much used to cover arbors, pergolas, lattices and to screen the sides of buildings, few climbing plants being more ornamental. Leaf, fruit and vine have been favorite subjects for reproduction by ornamentalists of all ages. As yet, however, it is seldom seen in cultivated landscapes except to secure shade and seclusion.
Grown for aesthetic purposes, the grape is seldom fruitful, for the vines can rarely be cultivated or deprived of their luxuriant growth as in the vineyard. Nevertheless, grapes grown as ornamentals can be trained so as to serve the double purpose of ornamental and fruit-bearing plant. Grown on the sides of a building, the grape often can be made to bear large crops of choicely fine fruit. The ancients had learned this, for the Psalmist says: "Thy wife shall be like the fruitful vine by the sides of thine house."
In all ornamental plantings on arbors or pergolas, if fruit is to be considered, the permanent trunk is carried to the top of the structure. Along this trunk, at intervals of eighteen inches, spurs are left from which to renew the wood from year to year. The vines should stand six or eight feet apart, depending on the variety, and one cane is left, three or four feet long, on each spur when the pruning is done. Shoots springing from these cover intermediate s.p.a.ces soon after growth begins. Provision, of course, must be made for a new cane each season, and this is done by saving a shoot springing from spur or trunk at pruning time.
The same method of training, with modifications to suit the case, may be employed on sides of buildings, walls, fences and lattices. If the object to be covered is low, however, and especially if fruit as well as a covering is wanted, perhaps a better plan is annually to renew from a low trunk or even back to the root. In this low renewal, a new cane, or two or three if desired, should be brought out each season, thus securing greater vigor for the vine, but greatly delaying, especially in the case of high walls, the production of a screen of foliage.
PRUNING AND TRAINING MUSCADINE GRAPES
The Muscadine grapes of the South are so distinct in characters of growth and fruit-bearing that their requirements as to pruning and training are quite different from the methods so far given. Until recent years when these grapes have become of commercial importance, it was thought by southern vineyardists that the Muscadines needed little or no pruning and some held that pruning injured the vines. Now it is found that Muscadines respond quite as readily as other types of grapes to pruning and training. Husmann and Dearing[15] give following directions for pruning Muscadines:
"Two systems of training are employed with Muscadine grapes: (1) The horizontal or overhead system, by which the growth is spread as an overhead canopy about 7 feet above the ground and supported by posts; and (2) the upright or vertical system, in which the growth is spread over a trellis.
"In the overhead system a single trunk is caused to grow erect from the ground alongside a permanent post. When the vine has reached the top of the post it is pinched in or cut back, so as to make it throw out shoots to grow and spread out from the head of the vine as the spokes of a wheel radiate from the hub. (The overhead training of Muscadines is shown in Fig. 21; upright training, in Fig. 22.)
[Ill.u.s.tration: FIG. 21. Rotundifolia vines trained by the overhead method.]
"In the upright systems the fruiting arms are either radiated from a low vine head, like the ribs of a fan, or they are taken off as horizontal arms from a central vertical trunk.
"Where the vineyard is not given close personal attention and pruning and other vineyard practices are neglected the best results will be obtained with the overhead trellis. Moreover, such a trellis permits cross-plowing and cultivation and is better adapted for grazing hogs, sheep, or cattle on cover crops grown in the vineyard. On the other hand, the careful vineyardist can expect the best and earliest results from vines on the upright or vertical supports. The upright trellis facilitates pruning, harvesting, spraying, and intercropping throughout the life of the vineyard; it is also easier to repair and can be erected from $10 to $20 an acre cheaper than the overhead trellis. The use of both the upright system and the overhead trellis has netted the growers profitable returns. Each has its advantages and disadvantages. The prospective grower, knowing his own conditions, must determine which training system is best suited to his conditions.
[Ill.u.s.tration: FIG. 22. A Rotundifolia vine trained by the 6-arm renewal method.]
"During the first year after planting, a strong stake reaching 4 feet above the ground at each vine is sufficient support. A trellis should be erected the second season, though the upper wires of an upright trellis and the secondary wires of an overhead trellis may be added later, as the vines need them. In erecting an upright trellis the posts should be set midway between the vines, the distances apart varying with the distances between the plants. The end posts of the rows should be firmly braced. Three wires are generally used, placed 24, 42, and from 56 to 60 inches from the ground.
"In erecting an overhead trellis, the usual method is to place a substantial, durable post reaching 7 feet above the ground at each of the permanent vines. Rows of extra heavy, well-braced posts, running parallel with and also at the ends of the rows of vines, are set at the boundaries of the vineyard. There are a number of different ways of arranging the wires. Usually No. 10 galvanized wires are securely fastened to the tops of the boundary posts on the four sides of a vineyard and then are run along and securely fastened on the tops of the inside post down each row in both directions as governor wires. As needed, No. 14 wires 2 feet apart are run parallel with the governor wires until in this manner the entire area has been covered.
"A cheaper but less durable overhead trellis is made by running No. 9 governor wires in only one direction and the secondary wires only at right angles to the governor wires, the secondary wires being fastened to the governor wires wherever they cross.
"Some growers construct arbors entirely of wood, using slats or poles instead of wires.
"The pruning of Muscadine grapes during the first three years is mainly for the purpose of establishing the permanent parts and adjusting the other parts of the vine to the desired training system for future usefulness. After that the pruning is primarily a matter of renewing the bearing surface and keeping the vines healthy, vigorous, and productive.
"During the first season the trunk of the vine should be established.
From this the main fruiting branches are started the second season.
These, under favorable circ.u.mstances, will bear a small crop of fruit the third season. After that the purpose of pruning should be to renew growth, to increase or decrease the bearing surface, and to maintain the shape of the vine.
"Severe pruning usually removes most of the fruit-bearing wood and throws the vine into vigorous wood growth. No pruning, on the other hand, causes a growth which is too much distributed, weak, and incapable of bearing good crops. Therefore, the grape grower should study the vines sufficiently to enable him to judge each year the proper severity of pruning for the best results. This will depend on the variety, the age of the vines, the fertility of the soil, etc.
Muscadine grapes bear their fruit in small cl.u.s.ters. It is therefore necessary to maintain a large fruiting surface in order to secure a proper tonnage of fruit. This is accomplished by developing a series of fruiting arms, spurring along these, and lengthening them as the vines become stronger. Such fruiting arms can be maintained for a number of years, but after a time it is desirable to renew them. This is done by cutting out the arm and starting a new one from a cane that has been previously grown for such purposes. It is preferable to renew systematically only one or, at most, two arms on a vine each year.
This gradual renewal does not disturb the vigor of the vine, but keeps it productive, healthy, and strong. The pruning can be quickly and easily done if systematically practiced from the time the vines are started."