Simple as pruning is, the pruner soon learns that it is an art in which perfection is better known in mind than followed in deed. The theory is easy but there are some stumbling blocks to make its consummation difficult. It is an art in which rules do not suffice, for no two vineyards can be pruned alike in amount or method, and every grape-grower finds his vineyard a proper field for the gratification of his taste in pruning. Happily, however, enlightened theory and sound practice are in perfect accord in grape-pruning, so that specific advice is well founded on governing principles. One cannot, of course, learn to prune unless he understands the habit of the grape-vine and is familiar with the terms applied to the different parts of the vine. As a preliminary to this chapter, therefore, knowledge of Chapter XVII, in which the structure of the grape-vine is discussed, is necessary. The next step is to distinguish between pruning and training. PRUNING AND TRAINING DISTINGUISHED The grape is pruned to increase in various ways the economic value of the plant by increasing the quantity and value of the crop. This is pruning proper. Or grapes are pruned to make well-proportioned plants with the parts so disposed that the vines are to the highest degree manageable in the vineyard. This is training. To repeat, the grape-plant is pruned to regulate the crop; it is trained to regulate the vine. Grape-growers usually speak of both operations as "pruning," but it is better to keep in mind the two conceptions. The distinctions between pruning and training must be made more apparent by setting forth in greater detail the results attained by the two operations. _Results attained in pruning to regulate the crop._ Proper pruning of vines in their first year in the vineyard, which, as we have seen, consists of cutting the young plants back severely, brings the vines in productive bearing a year or two years earlier than they would have borne had the pruning been neglected. This early pruning, since it is done with an eye to the vigor of each vine, insures greater uniformity in the growth and productiveness of the vineyard. Uniformity thus brought about is important not only for the time being, but for the future development of the vines, since weak vines, if unpruned, are stunted and may require years to overtake more vigorous vines in the vineyard.