CHAPTER X.

ON THE TRAINING OF VINES.

To train a vine on the surface of a wall, is to regulate the position of its branches, the principal objects of which, art, to protect them from the influence of the wind; to bring them into close contact with the wall, for the purpose of receiving the benefit of its warmth; to spread them at proper distances from each other, that the foliage and fruit may receive the full effect of the sun's rays; and to retard the motion of the sap, for the purpose of inducing the formation of fruit-buds.

The flow of sap, it must be remembered, is always strongest in a vertical direction, and weakest in a downward one; thus, if a shoot be trained in the direction of a, fig. 1, the sap will

ascend with the greatest degree of force with which the strength of the roots can propel it; if it be trained in the direction of b, c, or d, that force will be gradually diminished, as the shoot approaches the horizontal position of d; nevertheless, the difference in the flow of the sap betwixt the shoot at a, and that at d, will not be very great. Immediately, however, the horizontal line d, is passed, and the shoot depressed below it in the direction of e, the sap receives a considerable check, and the shoots that push from it are proportionately weak. If trained in the direction of f, they will be weaker still, and if directly downwards as at g, the supply of sap will be barely sufficient to mature the fruit. And, further, if the shoot, instead of being trained in a straight line, be bent in a crooked or serpentine manner, the flow of the sap will be additionally retarded. Thus, if it be trained in a serpentine manner, resembling the line h, fig. 2,

the sap will flow slower than if trained in a

straight line; if like the lines i, k, l, successively slower, the degree of slowness increasing in proportion to the number of bends or curves which the shoot is made to assume. If, therefore, the shoot g, fig. 1, be closely serpentined in the manner of the line 7, fig. 2, the sap will be so retarded, that many of the buds will not burst at all.

Now, to apply to a practical purpose, this principle of retarding the ascent of the sap, by depressing or serpentining the shoots of a vine, it will be convenient to treat of it in reference to winter training and summer training.

Winter training. When the shoots are nailed to the wall in the early part of the

year, those which are trained at full length as fruit-bearers, are, in all cases, to be cut down to the lowermost bud or two at the next autumnal pruning. With respect, therefore, to all such shoots, no greater supply of sap should be permitted to flow into them, than is necessary to mature their fruit, as all above that quantity will be so much nourishment uselessly expended, and taken, indeed, from the young shoots that are to be produced in the current year for future bearers. For

example, if the shoots 1, 2, 3, 4, fig. 3, were

Fig. 3.

a

a

Ꮓ

D

trained in straight lines, the sap would ascend with such force, that many of the lowermost buds would scarcely break at all, the sap passing by them, and accumulating in those at the upper part of the shoots, which would burst with great force, and form very strong shoots; these would rob all the fruit on those below of its due share of nourishment, and also the shoots emitted from the spurs D; which, to form good bearing-wood, require as great a supply as the fruiting-shoots. It is true, that, by pinching off the extremities of these latter ones in the spring, an eye or two above the last bunch of fruit, the sap will be

partially kept back, but the ascending current having set in very strongly, it cannot be diverted into the other channels in which it is required, except in a comparatively trifling degree. But, if, as represented in the above figure, the shoots be trained in a serpentine manner in the early part of the year, before the sap is in motion, it will, in its ascent, be thereby made to flow more equally into all the fruiting-shoots that push from them, and also into those which will be emitted from the spurs D, for future bearers. And by bending the bottom part of the shoots pretty circularly at a, the buds will there burst strongly, and thus a good supply of bearing-wood will be obtained close to the arms Z, Z, which is of primary importance; for, if by injudicious pruning or training, or both combined, the sap have an opportunity of exerting its full force at a distance from the arms, it is sure to embrace it, and the consequence is, that blank wood begins immediately to be formed in all directions near the stem, and when that is the case, no method of pruning will ever again procure a supply of bearing-wood at home, short of that of cutting the vine down to a perfect stump. In training the shoots 1, 2, 3, 4, the spaces between them must be regulated by the number of shoots intended to be trained up from the spurs D. Each of these latter will require five inches of clear space on each side of it, and the former, nine,