50 INTERNATIONAL CONGRESS OF VITICULTURE 



to the soil, root easily and be resistant, but not be congenial to the vinifera 

 varieties it is desired to graft; or the congeniality might otherwise be good 

 but the fruitfulness of the graft be impaired. Then again, in many cases, no 

 species of resistant is entirely suited to the soil and climatic conditions. 



In order to overcome such and other difficulties, hybrids are being pro- 

 duced, using as parents, in breeding, native American species possessing 

 the various qualities desired. A number of the best resistant stocks are 

 hybrids of this nature. We are testing an extensive assortment of such 

 hybrids and so called direct producers, hybrids between vinifera and Ameri- 

 can Euvitis, some of which it is hoped will produce sufficient fruit of desirable 

 qualities and prove resistant, thereby eliminating considerations of con- 

 geniality and cost of grafting. 



It has been ascertained that the same vinifera varieties grafted on dif- 

 ferent resistant stocks are sweeter on one, more acid on another, ripen 

 earlier on some, later on others, are more productive on some stocks than 

 on others; in fact often are entire successes on some stocks and failures 

 on others. This shows the ideal conditions are the best adapted resistant 

 stock, tops producing the finest fruit of sufficient quantity, and congeniality 

 between tops and bottoms permanent and good. 



There are more than nine hundred varieties under test in the Depart- 

 ment's Pacific Slope Experiment Vineyards. Bureau of Plant Industry 

 Bulletin No. 172 gives full account of the Department's Viticultural researches 

 in vinifera regions up to the time the bulletin was written. United States 

 Department of Agriculture Bulletin No. 209 gives a full account of such 

 researches since then to date. 



March 27, 1915. 



PRUNING AND TRAINING AMERICAN GRAPES. 



By F. E. GLADWIN. 

 Vineyard Laboratory Fredonia, N. Y. 



The questions of how a variety should be pruned, long or short, when 

 the pruning should be done, and how the canes should be disposed upon the 

 trellis are ever recurrent. They come not only from the beginner in com- 

 mercial grape growing, the garden grape fancier but, in large numbers, from 

 vineyardists of many years' experience. It is probable that no one phase 

 of grape growing is so little understood in its fundamentals as this sub- 

 ject. One of the causes that has contributed to this condition in a large 

 measure, in certain sections of eastern United States, is the all too common 

 practice of leaving the pruning to professional pruners, who see the vineyard 

 at but the one season of the year and hence are unfamiliar with it during 

 the growing period. The sole basis in this instance, for determining the 

 amount of fruiting wood to be left, is the amount of wood made during the 

 previous season. It is a well-known fact that the Concord may, in some 

 cases, make a very vigorous growth of wood and yet fail to mature its fruit 

 properly. Without this information the professional pruner cannot prune 

 intelligently. We have growing on our Experiment Grounds a Concord 

 vineyaid eight years set. Each year the vines make a large wood growth, 

 and if one were to judge from this alone, it would appear that at least ten 



