4.68 FUNDAMENTALS OF FRUIT PRODUCTION 



methods have been worked out and described in detail and an examina- 

 tion of any considerable part of this literature is as likely to be confusing 

 as it is enlightening. This is not because the several practices differ so 

 much in the principles involved, but because there is so great diversity in 

 the methods of their application that the principles themselves are 

 likely to remain hidden. 



As pointed out in the classification of bearing habits, the grape pro- 

 duces its fruit buds laterally on shoots, which at the close of the growing 

 season and for a year thereafter are called canes. These fruit buds give 

 rise to flower-bearing or fruiting shoots on which the inflorescences appear 

 to be lateral. However, many shoots form few or no fruit buds, particu- 

 larly those springing from latent or adventitious buds on 2-year-old 

 or older wood — in Other words, those arising from the arms, head, trunk 

 or crown of the plant. Only those shoots (canes, when a year old) coming 

 from lateral buds on the canes of the preceding season are sure to form 

 fruit buds, though under some conditions those coming from the older 

 wood differentiate a limited number. Furthermore not all buds on shoots 

 springing from the preceding year's canes contain flower parts. Those 

 at the basal one to four or five nodes, depending largely on variety, seldom 

 do. Though it is difficult, and often impossible, to distinguish the fruit 

 buds from the leaf or wood buds by their external appearance, their 

 position on the plant offers a rather accurate index to their character 

 and the grower or student, once he becomes well acquainted with the 

 characteristics of the individual variety, will have little difficulty in telling 

 which are of the one kind and which of the other. 



Severity of Pruning. — Practically all grape vines differentiate each 

 year more fruit buds than can grow into fruiting shoots and set and mature 

 grapes the following season. It is therefore unnecessary in pruning the 

 grape to give thought to securing larger numbers of fruit buds. The real 

 problem is that of reducing to just the right number those that are already 

 formed and normally would or could produce fruiting shoots the following 

 season. Furthermore, this must be done in such a way that the fruit 

 will be well distributed and that the new shoots on which fruit buds for a 

 succeeding crop are differentiated will be so located as to preserve the 

 compactness and established form of the vine. 



The reduction of fruit buds to just the right number is often difficult 

 and always requires an accurate knowledge of fruit-bud location in the 

 particular variety and good judgment as to how much fruit the vine 

 should bear. Overpruning reduces the crop and diverts the energies of 

 the plant into excessive wood growth. This is well illustrated by the 

 work of Maney^"* in Iowa. Underpruning permits the plant to overbear, 

 resulting in too many clusters, undersized berries of inferior quality and a 

 weakening of the vine itself so that succeeding crops will be reduced in 

 size and the life of the plant shortened. These statements, of course, 



