1911 Encyclopædia Britannica/Vine

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VINE. The grape-vine, botanically Vitis, is a genus of about thirty species, widespread in the north temperate zone, but richest in species in North America. The best known and longest cultivated species is the old-world grape-vine, Vitis vinifera; a variety of this, silvestris, occurs wild in the Mediterranean region, spreading eastwards towards the Caucasus and northwards into southern Germany, and may be regarded as the parent of the cultivated vine. It is of interest to note that grape-stones have been found with mummies in Egyptian tombs of not later age than 3000 years. The seeds have the characteristics of those of V. vinifera, but show some very slight variations from the type of seed now prevalent. Among the Greeks in the time of Homer wine was in general use. The cultivation of the vine must also have been introduced into Italy at a very early period. In Virgil's time the varieties in cultivation seem to have been exceedingly numerous; and the varied methods of training and culture now in use in Italy are in many cases identical with those described by Columella and other Roman writers. Grape-stones have been found among the remains of Swiss and Italian lake dwellings of the Bronze period, and others in tufaceous volcanic deposits near Montpellier, not long before the historic era.

The old-world, species is also extensively cultivated in California, but the grape industry of the eastern United States has been developed from native species, chiefly V. Labrusca and V. aestivalis and their hybrids with V. vinifera. Some of the American varieties have been introduced into France and other countries infested with Phylloxera, to serve as stocks on which to graft the better kinds of European vines, because their roots, though perhaps equally subject to the attacks of the insects, do not suffer so much injury from them as the European species.

The vine requires a high summer temperature and a prolonged period in which to ripen its fruit. Where these are forthcoming, it can be profitably cultivated, even though the winter temperature be very low. Tchihatchef mentions that at Erivan in Russian Armenia the mean winter temperature is 7° 1΄ C. and falls in January to -30° C., and at Bokhara the mean temperature of January is 4° C. and the minimum -22° C., and yet at both places the vine is grown with success. In the Alps it is profitably cultivated up to an altitude of 1870 ft., and in the north of Piedmont as high as 3180 ft. At the present time the limit of profitable cultivation in Europe passes from Brittany, lat. 47° 30΄, to beyond the Rhine by Liege and through Thuringia to; Silesia in lat. 51° 55'. In former centuries vines were cultivated to the north of this region, as, for instance, in Holland, in Belgium largely, and in England, where they might still be grown. Indeed, experiments have been made in this direction near Cardiff in South Wales. The yield is satisfactory, and the wine made, the variety known as Camay noir, is described as being like still champagne. In the middle ages, owing to various causes, the better wines of France and Germany could not be obtained in England except at prohibitive prices; but when this state of things ceased, and foreign wine could be imported, the English consumers would no longer tolerate the inferior productions of their own vineyards. It is also probable that the English mixed sugar or honey with the wine and thus supplied artificially that sweetness which the English sun denied. It is a curious fact that at the present day much or even most of the wine of finest quality is made at or near to the northern limits of possible cultivation with profit. This circumstance is probably explained by the greater care and attention bestowed both on the cultivation of the vine and on the manufacture of the wine in northern countries than in those where the climate is more propitious. The relative inferiority of the wines made at the Cape of Good Hope and in Australia is partly due to variations of climate, the vine not yet having adapted itself to the new conditions, and partly to the deficient skill of the manufacturers. That such inferiority may be expected to disappear is suggested by the success of vine-culture in Madeira and the Canary Islands.

The development of other species of Vitis, such as the curious succulent species of the Soudan and other parts of equatorial Africa, or the numerous kinds in India and Cochin China, is of course possible under suitable conditions; but it is obvious that an extremely long period must elapse before they can successfully compete with the product of many centuries.

[See also generally the article Wine. For currants and raisins, both produced by varieties of the grape-vine, see the respective articles.]

Apart from their economic value, vines are often cultivated for purely ornamental purposes, owing to the elegance of their foliage, the rich coloration they assume, the shade they afford, and their hardihood.

Vines have woody climbing stems, with alternate, entire or palmately lobed leaves, provided at the base with small stipules. Opposite some of these leaves springs a tendril, by aid of which the plant climbs. There are numerous transitional states between the ordinary form of tendril and the inflorescence. The flowers are small, green and fragrant, and are arranged in dense clusters. Each has a small calyx in the form of a shallow rim, sometimes five-lobed or toothed; five petals, which cohere by their tips and form a cap or hood, which is pushed off when the stamens are ripe; and five free stamens, placed opposite the petals and springing from a fleshy ring or disk surrounding the ovary; each bears a two celled anther. The anomalous position of the stamens in front of the petals is explained by the abortion or non-development of an outer row of stamens, indications of which are sometimes seen on the hypogynous disk encircling the ovary. The ovary bears a sessile stigma and is more or less completely two-celled, with two erect ovules in each cell. This ripens into the berry and seed. The cultivated vine has usually hermaphrodite flowers; but as it occurs in a wild state, or as an escape from cultivation, the flowers manifest a tendency towards unisexuality; that is, one plant bears flowers with stamens only, or only the rudiments of the pistil, while on another plant the flowers are bisexual. Exclusively female flowers without stamens do not appear to have been observed. Seedling plants from the cultivated vines often produce unisexual flowers, thus reverting to the feral type. Perhaps the explanation of the fact that some of the cultivated varieties are, as gardeners say, "bad setters,"—i.e. do not ripen their fruit owing to imperfect fertilization,—is to be sought in this natural tendency to dioecism.

EB1911 Vine.jpg
Fig. 1.—Vine.

1. Foliage, tendril and inflorescence, reduced.
2. Flower after fall of petals, magnified.
3. Fruit, reduced.

The conformation of the vine stem has elicited a vast amount of explanatory comment. The most generally accepted explanation is the "sympodial" one. According to this, the shoot of the vine is a "sympodium," consisting of a number of "podia" placed one over the other in longitudinal series. Each podium consists of a portion of the stem bearing one or more leaves, each with an axillary bud or buds, and terminating in a tendril or an inflorescence. In V. Labrusca there is a tendril opposite to each leaf, so that the podium bears only a single leaf. In other species there is a definite arrangement of the leaves, some with and others without tendrils opposite to them, the numerical order remaining constant or nearly so. These arrangements have doubtless some reference to climatic phenomena, continuity of growth being arrested by cold and promoted by warmth. In any case, it is obvious that these facts might be turned to practical ends in cultivation. A vine, for instance, that produces bunches of grapes at each joint is preferable to one in which there are several barren joints, as a larger quantity can be grown within a smaller area. The practice of pruning or "stopping" is, consciously or unconsciously, regulated by the mode of growth. The tendril or inflorescence, according to the views above explained, though in reality terminal, is bent to one side; hence it appears to be lateral and opposite to the leaf. While the tendril is thus diverted from its original direct course, the axillary bud of the leaf opposite the tendril begins a new podium, by lengthening into a shoot which assumes the direction the tendril had prior to its deflexion. This new podium, now in a direct line with its predecessor, produces leaves and ends in its turn in a tendril or inflorescence. A third podium succeeds the second, and so on. Other authorities explain the formation of the tendril and its anomalous position opposite to a leaf by supposing that the end of the stem bifurcates during growth, one division forming the shoot, the other the tendril or inflorescence. It is not possible within the limits at our command to specify the facts and arguments by which these theories are respectively supported. Practically the tendrils assist the plant in its native state to scramble over rocks or trees. As in the case of similar formations generally, they are endowed with a sensitiveness to touch which enables them to grasp and coil themselves round any suitable object which comes in their way, and thus to support the plant. The seeds or grape-stones are somewhat club-shaped, with a narrow neck-like portion beneath, which expands into a rounded and thickened portion above. On the inner or central side of the seed is a ridge bounded on either side by a shallow groove. This ridge indicates the point of union of the "raphe" or seed-stalk with the seed; it serves to distinguish the varieties of V. vinifera from those of other species. In endeavouring to trace the filiation and affinities of the vine, the characters afforded by the seed are specially valuable, because they have not been wittingly interfered with by human agency. Characters derived from the size, colour or flavour of the berry are of less value for historical or genealogical purposes than those which are the outcome of purely natural conditions.

The vine is hardy in Britain so far as regards its vegetation, but not hardy enough to bring its fruit to satisfactory maturity, so that for all practical purposes the vine must be regarded as a tender fruit. Planted against a wall or a building having a south aspect, or trained over a sunny roof, such sorts as the Black Cluster, Black Prince, Pitmaston White Cluster, Royal Muscadine, Sweetwater, &c., will ripen in the warmest English summers so as to be very pleasant eating; but in cold summers the fruit is not eatable in the raw state, and can only be converted into wine or vinegar. For outdoor culture the long-rod system is generally preferred.

When the plant is grown under glass, the vine border should occupy the interior of the house and also extend outwards in the front, but it is best made by instalments of 5 or 6 ft. as fast as the previous portions become well filled with roots, which may readily be done by packing up a turf wall at the extremity of the portion to be newly made; an exterior width of 15 ft. will be sufficient. If the soil beyond this is very unfavourable, the roots should be prevented from entering it by building a wall at the extreme edge of the border. Inside borders require frequent and thorough watering's. In well-drained localities the border may be partially below the ground level, but in damp situations it should be made on the surface; in either case the firm solid bottom should slope outwards towards an efficient drain. A good bottom may be formed by chalk rammed down close. On this should be laid at least a foot thick of coarse, hard, rubbly material, a layer of rough turf, grass side downwards, being spread over it to prevent the compost from working down. The soil itself, which should be 21/2 or 3 ft. deep, never less than 2 ft., should consist of live parts rich turfy loam, one part old lime rubbish or broken bricks, including a little wood ashes or burnt earth (ballast), one part broken charcoal, and about one part of half-inch bones, the whole being thoroughly mixed, and kept dryish till used. It is well after the borders are completed to remove the top soil, in which no roots are to be found, every two or three years, and to replace it with a mixture of good loam, rotten manure, lime rubbish and bone meal, to the depth of 6 or 7 in. A mulch of half-decayed stable litter is useful to prevent loss of moisture in summer.

Young vines raised from eyes, i.e. buds having about 1/2 in. wood above and 1 in. below, are generally preferred for planting. The eyes being selected from well-ripened shoots of the previous year are planted about the end of January, singly, in small pots of light loamy compost, and after standing in a warm place for a few days should be plunged in a propagating bed, having a bottom heat of 75°, which should be increased to 85° when they nave produced several leaves, the atmosphere being kept at about the same temperature or higher by sun heat during the day, and at about 75° at night. As soon as roots are freely formed the plants must be shifted into 6-inch pots, and later on into 12-inch ones. The shoots are trained up near the glass, and, with plenty of heat (top and bottom) and of water, with air and light, and manure water occasionally, will form firm, strong, well-ripened canes in the course of the season. To prepare the vine for planting, it should be cut back to within 2 ft. of the pot early in the season, and only three or four of the eyes at the base should be allowed to grow on. The best time for planting is in spring, when the young shoots have just started. The vines should be planted inside the house, from 1 to 2 ft. from the front wall, and from 6 ft. to 8 ft. apart, the roots being placed an inch deeper in the soil than before, carefully disentangled and spread outwards from the stem, and covered carefully and firmly with friable loam, without manure. When the shoots are fairly developed, the two strongest are to be selected and trained in. When forcing is commenced, the vinery is shut up for two or three weeks without fire heat, the mean temperature ranging about 50°. Fire heat must be at first applied very gently, and may range about 55° at night, and from 65° to 70° by day, but a few degrees more may be given them as the buds break and the new shoots appear. When they are in flower, and onwards during the swelling of the berries, 85° may be taken as a maximum, running up to 90° with sun heat and the temperature may be lowered somewhat when the fruit is ripe. The temperature must, however, be regulated according to the variety. Muscats requiring a higher temperature from the time their bunches show than Hamburghs. As much ventilation as the state of the weather will permit should be given. A moist growing atmosphere is necessary both for the swelling fruit and for maintaining the health of the foliage. A due amount of moisture may be kept up by the use of evaporating troughs and by syringing the walls and pathways two or three times a day, but the leaves should not be syringed. When the vines are in flower, and when the fruit is colouring, the evaporating troughs should be kept dry, but the aridity must not be excessive, lest the red spider and other pests should attack the leaves. In the course of the season the borders (inside) will require several thorough soakings of warm water—the first when the house is shut up, this being repeated when the vines have made young shoots a few inches long, again when the vines are in flower, and still again when the berries are taking the second swelling after stoning. Outside borders require watering in very dry summer weather only.

EB1911 Vine, Disease.jpg
Fig. 2.

1. Vine leaf attacked by mildew, Uncinula necator (Erysiphe Tuckeri), which forms white patches on the upper face, reduced.
2. Grapes similarly attacked.
3. Portion of the mycelium of the fungus bearing spores (conidia). s, on erect branches.
4. Perithecium or "fruit" of the fungus with its curled appendages.
5. Ascus from perithecium containing six spores.

There are three principal systems of pruning vines, termed the long-rod, the short-rod and the spur systems, and good crops have been obtained by each of them. It is admitted that larger bunches are generally obtained by the long-rod than by the spur system. The principle of this mode of pruning is to train in at considerable length, according to their strength, shoots of the last year's growth for producing shoots to bear fruit in the present, these rods are afterwards cut away and replaced by young shoots trained up during the preceding summer; and these are in their turn cut out in the following autumn after bearing, and replaced by shoots of that summer's growth. By the short-rod system, short instead of long rods are retained, they are dealt with in a similar manner. The spur system has, however, become the most general. In this case the vines are usually planted so that one can be trained up under each rafter, or up the middle of the sash, the latter method being preferable. The shoots are cut back to buds close to the stem, which should be encouraged to form alternately at equal distances right and left, by removing those buds from the original shoot which are not conveniently placed. The young shoots from these buds are to be gently brought to a horizontal position, by bending them a little at a time, and tied in, and usually opposite about the fourth leaf the rudiments of a bunch will be developed. The leaf directly opposite the bunch must in all cases be preserved, and the young shoot is to be topped at one or two joints beyond the incipient fruit, the latter distance being preferable if there is plenty of room for the foliage to expand; the lateral shoots, which will push out after the topping, must be again topped above their first or second joints. If the bunches are too numerous they must be thinned before the flowers expand, and the berries also must be properly thinned out and regulated as soon as they are well set, care being taken, in avoiding overcrowding, that the bunches be not made too thin and loose.

The cultivation of vines in pots is very commonly practised with good results, and pot-vines are very useful to force for the earliest crop. The plants should be raised from eyes, and grown as strong as possible in the way already noted, in rich turfy loam mixed with about one-third of horse dung and a little bone dust. The temperature should be gradually increased from 60° to 80°, or 90° by sun heat, and a bottom heat a few degrees higher must be maintained during their growth. As the roots require more room, the plants should be shifted from 3-inch pots into those of 6, 12 or 15 in. in diameter, in any of which larger sizes they may be fruited in the following season, but, to be successful in this, the young rod produced must be thoroughly matured after it has reached, its limit of growth. The periodical thorough cleansing of the vine stems and every part of the houses is of the utmost importance. The number of varieties of grapes possessing some merit is considerable, but a very few of them will be found sufficient to supply all the wants of the cultivator. For general purposes nothing approaches the Black Hamburgh (including Frankonthal) in merit.

Fungoid Diseases.—The most destructive form of fungoid disease which attacks the vine is caused by a mildew, Uncinula necator (Erysiphe Tuckeri) (fig. 2). The disease was first noticed in England in 1845; in 1848 it appeared at Versailles; by 1851 it had spread through all the wine-producing countries of Europe, being specially virulent in the lands bordering on the Mediterranean; and in the following year it made its appearance in Madeira. Like the Phylloxera (q.v.; also Wine), the mildew is in its origin probably American. The disease is characterized by the appearance of a mycelium forming white or greyish-white patches on the young leaves; this spreads quickly and attacks the older leaves and branches, and ultimately reaches the grapes. At first these are marked only by small brown spots; but the spots spread and fuse together, the skin of the grape is destroyed, and the flesh decays, the seed only remaining apparently untouched. The disease spreads by the mycelium growing over the epidermis of the plant. The hyphae composing the mycelium are provided with haustoria which project into the cells of the affected part (fig. 3).

EB1911 Vine, Uncinula necator.jpg
Fig. 3.—Uncinula necator (Erysiphe Tuckeri). A and B, mycelium (m), with haustoria (h). (After de Bary.) In A several cells of the epidermis are indicated.

Some of the hyphae which project from the leaf bear spores (conidia), which are constricted off one at a time, and by their means the fungus is distributed (fig. 2, 3). The perithecia are only produced exceptionally in Europe, but this stage of the life-history is common in the United States and causes a widely spread disease among the American vines. The mildew is in its turn attacked by a fungus of the same tribe, Cicinnobolus Cesatii, which lives parasitically within the hyphae of its host, and at times even succeeds in destroying it. The means which have proved most efficacious, both as a remedy and a preventive of this disease, is to scatter flowers of sulphur over the vines, before the morning dew has evaporated. Another method is to boil one part of lime with three parts of sulphur, and to sprinkle the mixture over the affected plants.

Another fungus which attacks vines, especially those of America, is Plasmopara viticola, which has also been introduced from America to Europe. The mycelium spreads through the green parts of the plant, attacking the leaves, twigs and unripe grapes. On the upper side of the leaf, where it is first visible, it forms pale green irregular spots, which become darker in colour. On the under side of the leaf these patches are white and are composed of the spore-bearing hyphae. The leaf ultimately becomes dried up and brittle. The grapes which are attacked cease to grow, turn brown or white, and ultimately dry up and fall off. This disease has been successfully treated with a spray of copper sulphate and lime, or sulphate of iron; solutions of these salts prevent the conidia from germinating.

Anthracnose is the name usually given to a disease which was formerly known as "charbon," "pech" or "brenner." This disease is caused by the parasitism of Sphaceloma ampelinum, one of the Pyrenomycetous fungi (fig. 4). The fungus assails all the green parts of the vine, and injures the leaves and young shoots as much as it does the grape itself. The first sign of its presence is the appearance of a minute spot, which is greyish in the centre, with a brown border. This spot increases in size; in the stalks it assumes an oval shape, with its long axis parallel to the stalk, whilst in the leaves and grapes it is more or less circular in outline. The centre of the spots on the grapes becomes darker as the disease advances, and a red line appears dividing the dark brown border into an outer and an inner rim and giving a very characteristic appearance to the diseased plant. The surrounding tissue enlarges, so that the spots appear as if sunk in depressions, and bear a considerable resemblance to hailstone wounds. Later the spots on the leaves often drop out. The berries do not shrivel up as those do that are affected by the black rot. The mycelium of Sphaceloma grows just beneath the cuticle of the vine, through which it soon bursts, giving rise to a number of minute hyphae, which bear conidia. These are minute, oval, colourless spores, which serve to spread the disease over the vineyard and from place to place. The complete life-history of this form is at present unknown; and information as to where the fungus passes the winter, and m what form, would probably afford some useful indications as to the method that should be adopted to combat the disease. Anthracnose has been known in Europe for many years, but has only been observed in America since 1881, whither it was probably imported from the old world. As a preventive to its attacks the copper sulphate sprays and a solution (50%) of iron sulphate have been found very useful, as well as care in planting on well-drained soil that does not lie too low, the disease seldom appearing in dry, well-exposed vineyards.

EB1911 Vine, Sphaceloma ampelinum.jpg EB1911 Vine, Guignardia Bidwellii.jpg
Fig. 4.—Charbon or Anthracnose of Vine, caused by Sphaceloma ampelinum.

1. Portion of twig with discoloured patches, caused by the fungus.
2. Fruit attacked by the fungus (reduced).
Fig. 5.—Black Rot of Grapes, Guignardia Bidwellii.

1. Grapes attacked by the fungus; the fruit becomes black, hard and shrivelled.
2. Fructification of the fungus, entire and in section; the latter shows the asci containing as cos pores, much enlarged.
3. Single ascus, more enlarged, showing the eight contained spores.

EB1911 Vine, Rosellinia necatrix.jpg

From Hartig's Lchrbuch der Pftanzenireitkheilen, by permission of Julius Springer.
Fig. 6.—Rosellinia (Dematophora) necatrix.

A. Mycelium of the fungus attacking root of vine (reduced).
B. Portion of vine root, showing masses of fructification (perithecia) of the fungus (reduced).

A great deal of confusion still exists with regard to this disease. A similar disease which of late has frequently been found in England, and which is ascribed to the fungus Gloeosporium ampelophagum, is very similar to it. In their mode of attack, in the symptoms they produce, and in the result upon the grapes and the vine the two fungi are so much alike that for practical purposes they may be regarded as identical. Massee recommends that the shoots should be dredged with flowers of sulphur at intervals of ten days, while the disease continues to spread, a small quantity of quicklime in a finely powdered condition being added and the quantity of lime being increased at every application, not so as to exceed the sulphur, however. The iron sulphate solution should be used while the vines are in a dormant condition, and diseased parts should be cleared away and burned.

The black rot, like the Uncinula and Plasmopara, is also American in its origin. It has been known and observed there since 1848, but appeared for the first time in France in 1885. The disease is caused by a fungus, Guignardia Bidwellii (fig. 5) (Phoma uvicola), one of the Pyrenomycetes, and by some authorities it has been considered to be a further stage in the life-history of Sphaceloma ampelinum. The fungus is most conspicuous on the grapes, but the leaves and stems are also affected. The grapes are not assailed until nearly full-grown, when a brownish spot appears, which spreads over the whole grape. The latter for a time retains its plumpness, but on the appearance of little black pustules, which first occur on the part primarily affected, the grape begins to shrivel. This continues until the grape is reduced to a black hard mass, with the folds of skin pressed closely against the seed. The disease spreads from grape to grape, so that as a rule many of the grapes in a bunch are destroyed. The hyphae of the mycelium of this fungus are septate, with numerous short branches. The pustules on the surface are due to fructifications, pycnidia and spermagonia. The fungus passes the winter in the withered grapes which fall to the ground, and on these the mature form of the fungus (fig. 5, 2 and 3) is produced; hence every care should be taken to collect these and burn them. The use of the copper solutions mentioned above may also be recommended as a preventive.

Among the other fungi which infest the vine may be mentioned Phyllosticta viticola and Ph. Labruscae, which, when the attack is severe, cause the destruction of the leaves, the only part they assail. These, like the foregoing, are members of the Pyrenomycetes, while many other allied fungi have been described as causing spots on the leaves. Cercospora Vitis (Cladosporium viticolum), which has club-shaped spores of a green-brown colour, also attacks the leaves; but, unless the season is extremely unfavourable, it does little harm.

A very disastrous root-disease of the vine is due to the ravages of another pyrenomycetous fungus, Rosellinia (Dematophora) necatrix (fig. 6), which forms subterranean strings of mycelium so-called rhizomorphs. The diseased roots have been confounded with those attacked by Phylloxera. The only mode of combating the malady seems to be to uproot the plants and burn them. Isolation of the diseased areas by means of trenches has also been practised.