New Yokk Agricultural Experiment Station. 211 



SUMMARY OF RESULTS OBTAINED IN TEN-YEAR 

 EXPERIMENTS PRIOR TO 1911. 



RESULTS IN 1902. 

 Table I. — Yiexd by Sekies at Geneva in 1902. 



Series. 



I. 

 II. 



III. 



Rows.* 



1, 4. 7 and 13. 



2, 5, 8 and 14. 



3, 6, 9 and 15. 



Dates of spraying. 



July 10, 23 and Aug. 

 June 25, July 10, 23, 

 10, 



12 



30, Aug. 12, 26 and Sept. 



Not sprayed . 



Yield per acre.f 



Bu. 

 317 



342 

 219 



lbs. 

 41 



36 



4 



* Rows 10, 11 and 12 omitted because of probable error. 



t The yields given in Tables I to XVIII relate to marketable tubers only. 



Increase in yield due to spraying three times, 98|- hu. per acre. 

 Increase in yield due to spraying seven tinnes, 123^ bu. per acre. 



The iinsprajed rows died two weeks earlier than the sprayed 

 rows, owing chiefly to a severe attack of late blight. They were 

 also somewhat injured by flea beetles, but there was no early 

 blight. On unsprayed rows the loss from rot was 7| per ct. ; on 

 sprayed rows only an occasional tuber. 



Table II. — Yield by Series at Riverhead in 1902. 



Increase in yield due to spraying three times, 27f hu. per acre. 

 Increase in yield due to spraying seven times, 45 hu. per acre. 



In this experiment there were only traces of early blight and 

 no late blight. The larger yield on sprayed rows was due to par- 

 tial protection against flea beetles which were rather plentiful at 

 times. There was no rot. 



