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INTERNATIONAL CONGRESS OP VITICULTURE 



enough to support the above-ground portions of the plant; thus eliminating 

 the expense for stakes, labor and tying material. 



Table Showing Average Differences in Diameters of Stocks with All Scions. 



Name of No. of 

 No. Stock Scions 



1. Lenoir 8 



2. Chass. x Berl.41B....14 



3. Rup. St. George 17 



4. Mour. x Rup. 1202....15 



5. Rip. x Berl. 420A 13 



6. A x R G No. 9 2 



7. R. Martin 3 



8. R. Gloire 16 



9. Rip. x Rup. 3309 14 



10. Rip. x Rup. 101-14.... 4 



11. Rip. x Rup. 3306 16 



12. A x R G No. 1 5 



13. Rip. x Berl. 157-11.... 1 



Summary. 



Do the above facts and figures place us in a position to recommend the 

 grafting of certain vinifera grapes on certain resistant stocks? No. How- 

 ever, we have found Mourvedre x Rup. 1202, Riparia x Rupestris 3309, Ber- 

 landieri x Riparia 420, and Chass. x Berlandieri 41 B have given very satis- 

 factory results. Rupestris St. George, the most common stock in California, 

 makes a good growth but the crop is deficient in quantity, and whether this 

 bad peculiarity will disappear in time we are not prepared to say. The 

 Lenoir shows the least lack of affinity with the scions, grafted on to it, 

 but its low resistance to phylloxera and the inferior bearing of its grafts 

 make it useless as a resistant stock. 



The vines from which the above data have been obtained, are nearly all 

 four years old. We have been able to weigh, test for sugar and acidity but 

 one crop. We do not know whether the crop of certain varieties of grapes 

 on certain stocks will increase or decrease in the future, nor do we know 

 whether the lack of affinity between the stock and scion which always exists 

 to a more or less degree, as evidenced by the differences of diameters in the 

 stocks and scions, will increase or decrease when the vines get older. All 

 these are questions which can be answered in the future only. The "perfect" 

 phylloxera resistant stock which is satisfactory in every way, has thus far 

 not been produced. However, we hope in time to be able to find a suitable 

 stock for every commercial vinifera variety grown in California and every 

 soil condition. 



The observations of Prof. Flossfeder to the effect that after making 

 practical testrr it was found that the crop produced by varieties grafted on 

 Rupestris St. George showed less tonnage brought about an interesting discus- 

 sion and the experience of many growers was given, and showed the value 

 of the work of the Viticultural Department of the State of California and of 

 the United States Department of Agriculture. Mr. Louis Kunde, of Glen 

 Ellen, California, Mr. Swett, of Martinez, Mr. Sheehan, of Sacramento, Prof. 

 Husmann, of Washington, D. C., Mr. C. J. Wetmore, of San Francisco, Mr. 

 P. F. Goodwin, of Healdsburg, California, Prof. Bioletti, of the University of 

 California, and others took part in the discussion. 



